d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
53c0e1ff7d
freebsd-skq/sys/kern/kern_timeout.c

658 lines
19 KiB
C
Raw Normal View History

BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
/*-
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
* From: @(#)kern_clock.c 8.5 (Berkeley) 1/21/94
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
*/
Use __FBSDID().
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <sys/param.h>
#include <sys/systm.h>
A bunch of nits from bde.
1998-02-15 14:15:21 +00:00
#include <sys/callout.h>
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
#include <sys/condvar.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
#include <sys/kernel.h>
Cut a KTR record whenever a callout is invoked. Mark whether it runs with Giant or not, and include the function point so it can be looked up against the kernel symbol table during trace analysis.
2004-08-06 21:49:00 +00:00
#include <sys/ktr.h>
Catch up to header include changes: - <sys/mutex.h> now requires <sys/systm.h> - <sys/mutex.h> and <sys/sx.h> now require <sys/lock.h>
2001-03-28 09:17:56 +00:00
#include <sys/lock.h>
The recent changes to msleep() and mawait() resulted in timeout() and untimeout() not being called with Giant in those functions. For now, use the sched_lock to protect the callout wheel in softclock() and in the various timeout and callout functions. Noticed by: tegge
2000-11-16 21:20:52 +00:00
#include <sys/mutex.h>
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
#include <sys/sysctl.h>
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
static int avg_depth;
SYSCTL_INT(_debug, OID_AUTO, to_avg_depth, CTLFLAG_RD, &avg_depth, 0,
"Average number of items examined per softclock call. Units = 1/1000");
static int avg_gcalls;
SYSCTL_INT(_debug, OID_AUTO, to_avg_gcalls, CTLFLAG_RD, &avg_gcalls, 0,
"Average number of Giant callouts made per softclock call. Units = 1/1000");
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
static int avg_mtxcalls;
SYSCTL_INT(_debug, OID_AUTO, to_avg_mtxcalls, CTLFLAG_RD, &avg_mtxcalls, 0,
"Average number of mtx callouts made per softclock call. Units = 1/1000");
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
static int avg_mpcalls;
SYSCTL_INT(_debug, OID_AUTO, to_avg_mpcalls, CTLFLAG_RD, &avg_mpcalls, 0,
"Average number of MP callouts made per softclock call. Units = 1/1000");
A bunch of nits from bde.
1998-02-15 14:15:21 +00:00
/*
* TODO:
* allocate more timeout table slots when table overflows.
*/
/* Exported to machdep.c and/or kern_clock.c. */
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
struct callout *callout;
struct callout_list callfree;
int callwheelsize, callwheelbits, callwheelmask;
struct callout_tailq *callwheel;
A bunch of nits from bde.
1998-02-15 14:15:21 +00:00
int softticks; /* Like ticks, but for softclock(). */
Don't put callout_lock under #ifdef DIAGNOSTIC despite the fact that it works anyway.
2003-06-20 08:39:04 +00:00
struct mtx callout_lock;
Fix up some sloppy coding practices: - Delete redundant declarations. - Add -Wredundant-declarations to Makefile.i386 so they don't come back. - Delete sloppy COMMON-style declarations of uninitialized data in header files. - Add a few prototypes. - Clean up warnings resulting from the above. NB: ioconf.c will still generate a redundant-declaration warning, which is unavoidable unless somebody volunteers to make `config' smarter.
1994-08-18 22:36:09 +00:00
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
static struct callout *nextsoftcheck; /* Next callout to be checked. */
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
Adjust two of my comments to the new world order: Indent protection in the first column is performed using /**, not /*-.
2005-01-07 03:25:45 +00:00
/**
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
* Locked by callout_lock:
* curr_callout - If a callout is in progress, it is curr_callout.
* If curr_callout is non-NULL, threads waiting on
* callout_wait will be woken up as soon as the
* relevant callout completes.
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
* curr_cancelled - Changing to 1 with both callout_lock and c_mtx held
* guarantees that the current callout will not run.
* The softclock() function sets this to 0 before it
* drops callout_lock to acquire c_mtx, and it calls
* the handler only if curr_cancelled still 0 when
* c_mtx is successfully acquired.
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
* wakeup_ctr - Incremented every time a thread wants to wait
* for a callout to complete. Modified only when
* curr_callout is non-NULL.
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
* wakeup_needed - If a thread is waiting on callout_wait, then
* wakeup_needed is nonzero. Increased only when
* cutt_callout is non-NULL.
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
*/
static struct callout *curr_callout;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
static int curr_cancelled;
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
static int wakeup_ctr;
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
static int wakeup_needed;
Adjust two of my comments to the new world order: Indent protection in the first column is performed using /**, not /*-.
2005-01-07 03:25:45 +00:00
/**
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
* Locked by callout_wait_lock:
* callout_wait - If wakeup_needed is set, callout_wait will be
* triggered after the current callout finishes.
* wakeup_done_ctr - Set to the current value of wakeup_ctr after
* callout_wait is triggered.
*/
static struct mtx callout_wait_lock;
static struct cv callout_wait;
static int wakeup_done_ctr;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Move most of the kernel submap initialization code, including the timeout callwheel and buffer cache, out of the platform specific areas and into the machine independant area. i386 and alpha adjusted here. Other cpus can be fixed piecemeal. Reviewed by: freebsd-smp, jake
2001-08-22 04:07:27 +00:00
/*
* kern_timeout_callwheel_alloc() - kernel low level callwheel initialization
*
* This code is called very early in the kernel initialization sequence,
* and may be called more then once.
*/
caddr_t
kern_timeout_callwheel_alloc(caddr_t v)
{
/*
* Calculate callout wheel size
*/
for (callwheelsize = 1, callwheelbits = 0;
callwheelsize < ncallout;
callwheelsize <<= 1, ++callwheelbits)
;
callwheelmask = callwheelsize - 1;
callout = (struct callout *)v;
v = (caddr_t)(callout + ncallout);
callwheel = (struct callout_tailq *)v;
v = (caddr_t)(callwheel + callwheelsize);
return(v);
}
/*
* kern_timeout_callwheel_init() - initialize previously reserved callwheel
* space.
*
* This code is called just once, after the space reserved for the
* callout wheel has been finalized.
*/
void
kern_timeout_callwheel_init(void)
{
int i;
SLIST_INIT(&callfree);
for (i = 0; i < ncallout; i++) {
callout_init(&callout[i], 0);
callout[i].c_flags = CALLOUT_LOCAL_ALLOC;
SLIST_INSERT_HEAD(&callfree, &callout[i], c_links.sle);
}
for (i = 0; i < callwheelsize; i++) {
TAILQ_INIT(&callwheel[i]);
}
Change callers of mtx_init() to pass in an appropriate lock type name. In most cases NULL is passed, but in some cases such as network driver locks (which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used. Tested on: i386, alpha, sparc64
2002-04-04 21:03:38 +00:00
mtx_init(&callout_lock, "callout", NULL, MTX_SPIN | MTX_RECURSE);
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
mtx_init(&callout_wait_lock, "callout_wait_lock", NULL, MTX_DEF);
cv_init(&callout_wait, "callout_wait");
Move most of the kernel submap initialization code, including the timeout callwheel and buffer cache, out of the platform specific areas and into the machine independant area. i386 and alpha adjusted here. Other cpus can be fixed piecemeal. Reviewed by: freebsd-smp, jake
2001-08-22 04:07:27 +00:00
}
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
/*
* The callout mechanism is based on the work of Adam M. Costello and
* George Varghese, published in a technical report entitled "Redesigning
* the BSD Callout and Timer Facilities" and modified slightly for inclusion
* in FreeBSD by Justin T. Gibbs. The original work on the data structures
The paper "Hashed Timers and Hierarchical Wheels: Data Structures for the Efficient Implementation of a Timer Facility" was co-author'ed by T. Lauk, not A. Lauk. Adjust nearby whitespace.
2004-04-25 04:10:17 +00:00
* used in this implementation was published by G. Varghese and T. Lauck in
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
* the paper "Hashed and Hierarchical Timing Wheels: Data Structures for
* the Efficient Implementation of a Timer Facility" in the Proceedings of
* the 11th ACM Annual Symposium on Operating Systems Principles,
* Austin, Texas Nov 1987.
*/
Effect the divorce of kern_clock.c and kern_timeout.c (which was repository copied from kern_clock.c)
1998-01-10 13:16:26 +00:00
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
/*
* Software (low priority) clock interrupt.
* Run periodic events from timeout queue.
*/
void
- Overhaul the software interrupt code to use interrupt threads for each type of software interrupt. Roughly, what used to be a bit in spending now maps to a swi thread. Each thread can have multiple handlers, just like a hardware interrupt thread. - Instead of using a bitmask of pending interrupts, we schedule the specific software interrupt thread to run, so spending, NSWI, and the shandlers array are no longer needed. We can now have an arbitrary number of software interrupt threads. When you register a software interrupt thread via sinthand_add(), you get back a struct intrhand that you pass to sched_swi() when you wish to schedule your swi thread to run. - Convert the name of 'struct intrec' to 'struct intrhand' as it is a bit more intuitive. Also, prefix all the members of struct intrhand with 'ih_'. - Make swi_net() a MI function since there is now no point in it being MD. Submitted by: cp
2000-10-25 05:19:40 +00:00
softclock(void *dummy)
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
Under DIAGNOSTIC, complain if a timeout(9) routine took more than 1msec.
2002-09-04 20:05:00 +00:00
struct callout *c;
struct callout_tailq *bucket;
int curticks;
int steps; /* #steps since we last allowed interrupts */
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
int depth;
int mpcalls;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
int mtxcalls;
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
int gcalls;
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
int wakeup_cookie;
At the request of several developers, restore the DIAGNOSIC code deleted in 1.81. Increase the initial timeout limit to 2ms to eliminate spurious messages of excessive timeouts in the NFS client code. Requested by: Poul-Henning Kamp <phk@phk.freebsd.dk> Requested by: Mike Silbersack <silby@silby.com> Requested by: Sam Leffler <sam@errno.com>
2003-11-12 22:28:27 +00:00
#ifdef DIAGNOSTIC
struct bintime bt1, bt2;
struct timespec ts2;
static uint64_t maxdt = 36893488147419102LL; /* 2 msec */
Make the DIAGNOSTIC code which complains about long {call|time}out(9) functions less noisy: We printf if a new function took longer than the previous record holder, or of the previous record holder took more than twice as long as the current record.
2003-12-07 20:03:28 +00:00
static timeout_t *lastfunc;
At the request of several developers, restore the DIAGNOSIC code deleted in 1.81. Increase the initial timeout limit to 2ms to eliminate spurious messages of excessive timeouts in the NFS client code. Requested by: Poul-Henning Kamp <phk@phk.freebsd.dk> Requested by: Mike Silbersack <silby@silby.com> Requested by: Sam Leffler <sam@errno.com>
2003-11-12 22:28:27 +00:00
#endif
Effect the divorce of kern_clock.c and kern_timeout.c (which was repository copied from kern_clock.c)
1998-01-10 13:16:26 +00:00
A bunch of nits from bde.
1998-02-15 14:15:21 +00:00
#ifndef MAX_SOFTCLOCK_STEPS
#define MAX_SOFTCLOCK_STEPS 100 /* Maximum allowed value of steps. */
#endif /* MAX_SOFTCLOCK_STEPS */
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
mpcalls = 0;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
mtxcalls = 0;
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
gcalls = 0;
depth = 0;
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
steps = 0;
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
while (softticks != ticks) {
Store an absolute tick value in callout entries so that a subtraction on hash chain traversal isn't needed. This also allows untimeout to recompute the hash to find the bucket that the entry to remove is stored in so that each callout entry no longer needs to store that information. Reviewed by: Nate Williams <nate@mt.sri.com>
1997-09-24 16:39:27 +00:00
softticks++;
/*
* softticks may be modified by hard clock, so cache
* it while we work on a given bucket.
*/
curticks = softticks;
bucket = &callwheel[curticks & callwheelmask];
c = TAILQ_FIRST(bucket);
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
while (c) {
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
depth++;
Store an absolute tick value in callout entries so that a subtraction on hash chain traversal isn't needed. This also allows untimeout to recompute the hash to find the bucket that the entry to remove is stored in so that each callout entry no longer needs to store that information. Reviewed by: Nate Williams <nate@mt.sri.com>
1997-09-24 16:39:27 +00:00
if (c->c_time != curticks) {
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
c = TAILQ_NEXT(c, c_links.tqe);
++steps;
if (steps >= MAX_SOFTCLOCK_STEPS) {
nextsoftcheck = c;
Store an absolute tick value in callout entries so that a subtraction on hash chain traversal isn't needed. This also allows untimeout to recompute the hash to find the bucket that the entry to remove is stored in so that each callout entry no longer needs to store that information. Reviewed by: Nate Williams <nate@mt.sri.com>
1997-09-24 16:39:27 +00:00
/* Give interrupts a chance. */
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
Axe spl's obsoleted by the callout mutex.
2001-08-10 01:36:25 +00:00
; /* nothing */
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
c = nextsoftcheck;
steps = 0;
}
} else {
void (*c_func)(void *);
void *c_arg;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
struct mtx *c_mtx;
- Protect the callout wheel with a separate spin mutex, callout_lock. - Use the mutex in hardclock to ensure no races between it and softclock. - Make softclock be INTR_MPSAFE and provide a flag, CALLOUT_MPSAFE, which specifies that a callout handler does not need giant. There is still no way to set this flag when regstering a callout. Reviewed by: -smp@, jlemon
2000-11-19 06:02:32 +00:00
int c_flags;
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
nextsoftcheck = TAILQ_NEXT(c, c_links.tqe);
Store an absolute tick value in callout entries so that a subtraction on hash chain traversal isn't needed. This also allows untimeout to recompute the hash to find the bucket that the entry to remove is stored in so that each callout entry no longer needs to store that information. Reviewed by: Nate Williams <nate@mt.sri.com>
1997-09-24 16:39:27 +00:00
TAILQ_REMOVE(bucket, c, c_links.tqe);
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
c_func = c->c_func;
c_arg = c->c_arg;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
c_mtx = c->c_mtx;
- Protect the callout wheel with a separate spin mutex, callout_lock. - Use the mutex in hardclock to ensure no races between it and softclock. - Make softclock be INTR_MPSAFE and provide a flag, CALLOUT_MPSAFE, which specifies that a callout handler does not need giant. There is still no way to set this flag when regstering a callout. Reviewed by: -smp@, jlemon
2000-11-19 06:02:32 +00:00
c_flags = c->c_flags;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
if (c->c_flags & CALLOUT_LOCAL_ALLOC) {
Make "c->c_func = NULL" conditional on the CALLOUT_LOCAL_ALLOC flag, i.e., only clear c->c_func if the callout c is being used via the old timeout(9) interface. Requested by: glebius
2005-01-19 20:34:46 +00:00
c->c_func = NULL;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
c->c_flags = CALLOUT_LOCAL_ALLOC;
SLIST_INSERT_HEAD(&callfree, c,
c_links.sle);
When processing a timeout() callout and returning it to the free list, set `curr_callout' to NULL. This ensures that we won't attempt to cancel the current callout if the original callout structure gets recycled while we wait to acquire Giant. This is reported to fix an intermittent syscons problem that was introduced by revision 1.96.
2005-02-11 00:14:00 +00:00
curr_callout = NULL;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
} else {
c->c_flags =
Restructure TCP timeout handling: - eliminate the fast/slow timeout lists for TCP and instead use a callout entry for each timer. - increase the TCP timer granularity to HZ - implement "bad retransmit" recovery, as presented in "On Estimating End-to-End Network Path Properties", by Allman and Paxson. Submitted by: jlemon, wollmann
1999-08-30 21:17:07 +00:00
(c->c_flags & ~CALLOUT_PENDING);
When processing a timeout() callout and returning it to the free list, set `curr_callout' to NULL. This ensures that we won't attempt to cancel the current callout if the original callout structure gets recycled while we wait to acquire Giant. This is reported to fix an intermittent syscons problem that was introduced by revision 1.96.
2005-02-11 00:14:00 +00:00
curr_callout = c;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
}
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
curr_cancelled = 0;
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if (c_mtx != NULL) {
mtx_lock(c_mtx);
/*
* The callout may have been cancelled
* while we switched locks.
*/
if (curr_cancelled) {
mtx_unlock(c_mtx);
mtx_lock_spin(&callout_lock);
goto done_locked;
}
/* The callout cannot be stopped now. */
curr_cancelled = 1;
if (c_mtx == &Giant) {
gcalls++;
CTR1(KTR_CALLOUT, "callout %p",
c_func);
} else {
mtxcalls++;
CTR1(KTR_CALLOUT,
"callout mtx %p",
c_func);
}
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
} else {
mpcalls++;
Cut a KTR record whenever a callout is invoked. Mark whether it runs with Giant or not, and include the function point so it can be looked up against the kernel symbol table during trace analysis.
2004-08-06 21:49:00 +00:00
CTR1(KTR_CALLOUT, "callout mpsafe %p",
c_func);
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
}
At the request of several developers, restore the DIAGNOSIC code deleted in 1.81. Increase the initial timeout limit to 2ms to eliminate spurious messages of excessive timeouts in the NFS client code. Requested by: Poul-Henning Kamp <phk@phk.freebsd.dk> Requested by: Mike Silbersack <silby@silby.com> Requested by: Sam Leffler <sam@errno.com>
2003-11-12 22:28:27 +00:00
#ifdef DIAGNOSTIC
binuptime(&bt1);
#endif
Replace the dont_sleep_in_callout mutex hack (similar to g_x{up,down}) with the disallow sleeping facility.
2005-09-15 20:09:08 +00:00
THREAD_NO_SLEEPING();
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
c_func(c_arg);
Replace the dont_sleep_in_callout mutex hack (similar to g_x{up,down}) with the disallow sleeping facility.
2005-09-15 20:09:08 +00:00
THREAD_SLEEPING_OK();
At the request of several developers, restore the DIAGNOSIC code deleted in 1.81. Increase the initial timeout limit to 2ms to eliminate spurious messages of excessive timeouts in the NFS client code. Requested by: Poul-Henning Kamp <phk@phk.freebsd.dk> Requested by: Mike Silbersack <silby@silby.com> Requested by: Sam Leffler <sam@errno.com>
2003-11-12 22:28:27 +00:00
#ifdef DIAGNOSTIC
binuptime(&bt2);
bintime_sub(&bt2, &bt1);
if (bt2.frac > maxdt) {
Make the DIAGNOSTIC code which complains about long {call|time}out(9) functions less noisy: We printf if a new function took longer than the previous record holder, or of the previous record holder took more than twice as long as the current record.
2003-12-07 20:03:28 +00:00
if (lastfunc != c_func ||
bt2.frac > maxdt * 2) {
bintime2timespec(&bt2, &ts2);
printf(
"Expensive timeout(9) function: %p(%p) %jd.%09ld s\n",
c_func, c_arg,
(intmax_t)ts2.tv_sec,
ts2.tv_nsec);
}
At the request of several developers, restore the DIAGNOSIC code deleted in 1.81. Increase the initial timeout limit to 2ms to eliminate spurious messages of excessive timeouts in the NFS client code. Requested by: Poul-Henning Kamp <phk@phk.freebsd.dk> Requested by: Mike Silbersack <silby@silby.com> Requested by: Sam Leffler <sam@errno.com>
2003-11-12 22:28:27 +00:00
maxdt = bt2.frac;
Make the DIAGNOSTIC code which complains about long {call|time}out(9) functions less noisy: We printf if a new function took longer than the previous record holder, or of the previous record holder took more than twice as long as the current record.
2003-12-07 20:03:28 +00:00
lastfunc = c_func;
At the request of several developers, restore the DIAGNOSIC code deleted in 1.81. Increase the initial timeout limit to 2ms to eliminate spurious messages of excessive timeouts in the NFS client code. Requested by: Poul-Henning Kamp <phk@phk.freebsd.dk> Requested by: Mike Silbersack <silby@silby.com> Requested by: Sam Leffler <sam@errno.com>
2003-11-12 22:28:27 +00:00
}
#endif
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if ((c_flags & CALLOUT_RETURNUNLOCKED) == 0)
mtx_unlock(c_mtx);
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
done_locked:
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
curr_callout = NULL;
if (wakeup_needed) {
/*
* There might be someone waiting
* for the callout to complete.
*/
wakeup_cookie = wakeup_ctr;
mtx_unlock_spin(&callout_lock);
mtx_lock(&callout_wait_lock);
cv_broadcast(&callout_wait);
wakeup_done_ctr = wakeup_cookie;
mtx_unlock(&callout_wait_lock);
mtx_lock_spin(&callout_lock);
wakeup_needed = 0;
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
}
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
steps = 0;
c = nextsoftcheck;
}
}
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
avg_depth += (depth * 1000 - avg_depth) >> 8;
avg_mpcalls += (mpcalls * 1000 - avg_mpcalls) >> 8;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
avg_mtxcalls += (mtxcalls * 1000 - avg_mtxcalls) >> 8;
Add instrumentation which tells us how much work softclock() does per invocation.
2003-06-04 05:25:58 +00:00
avg_gcalls += (gcalls * 1000 - avg_gcalls) >> 8;
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
nextsoftcheck = NULL;
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
/*
* timeout --
* Execute a function after a specified length of time.
*
* untimeout --
* Cancel previous timeout function call.
*
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
* callout_handle_init --
* Initialize a handle so that using it with untimeout is benign.
*
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
* See AT&T BCI Driver Reference Manual for specification. This
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
* implementation differs from that one in that although an
* identification value is returned from timeout, the original
* arguments to timeout as well as the identifier are used to
* identify entries for untimeout.
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
*/
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
struct callout_handle
timeout(ftn, arg, to_ticks)
Declare function pointer args as pointers, not as functions.
1998-02-25 06:13:32 +00:00
timeout_t *ftn;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
void *arg;
Revert the last commit to the callout interface, and add a flag to callout_init() indicating whether the callout is safe or not. Update the callers of callout_init() to reflect the new interface. Okayed by: Jake
2000-11-25 06:22:16 +00:00
int to_ticks;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
struct callout *new;
struct callout_handle handle;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
/* Fill in the next free callout structure. */
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
new = SLIST_FIRST(&callfree);
if (new == NULL)
/* XXX Attempt to malloc first */
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
panic("timeout table full");
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
SLIST_REMOVE_HEAD(&callfree, c_links.sle);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
callout_reset(new, to_ticks, ftn, arg);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
handle.callout = new;
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
return (handle);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
void
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
untimeout(ftn, arg, handle)
Declare function pointer args as pointers, not as functions.
1998-02-25 06:13:32 +00:00
timeout_t *ftn;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
void *arg;
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
struct callout_handle handle;
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
{
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
/*
* Check for a handle that was initialized
* by callout_handle_init, but never used
* for a real timeout.
*/
if (handle.callout == NULL)
return;
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
if (handle.callout->c_func == ftn && handle.callout->c_arg == arg)
callout_stop(handle.callout);
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
BSD 4.4 Lite Kernel Sources
1994-05-24 10:09:53 +00:00
}
init_main.c subr_autoconf.c: Add support for "interrupt driven configuration hooks". A component of the kernel can register a hook, most likely during auto-configuration, and receive a callback once interrupt services are available. This callback will occur before the root and dump devices are configured, so the configuration task can affect the selection of those two devices or complete any tasks that need to be performed prior to launching init. System boot is posponed so long as a hook is registered. The hook owner is responsible for removing the hook once their task is complete or the system boot can continue. kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c: Change the interface and implementation for the kernel callout service. The new implemntaion is based on the work of Adam M. Costello and George Varghese, published in a technical report entitled "Redesigning the BSD Callout and Timer Facilities". The interface used in FreeBSD is a little different than the one outlined in the paper. The new function prototypes are: struct callout_handle timeout(void (*func)(void *), void *arg, int ticks); void untimeout(void (*func)(void *), void *arg, struct callout_handle handle); If a client wishes to remove a timeout, it must store the callout_handle returned by timeout and pass it to untimeout. The new implementation gives 0(1) insert and removal of callouts making this interface scale well even for applications that keep 100s of callouts outstanding. See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
void
callout_handle_init(struct callout_handle *handle)
{
handle->callout = NULL;
}
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
/*
* New interface; clients allocate their own callout structures.
*
* callout_reset() - establish or change a timeout
* callout_stop() - disestablish a timeout
* callout_init() - initialize a callout structure so that it can
* safely be passed to callout_reset() and callout_stop()
*
Restructure TCP timeout handling: - eliminate the fast/slow timeout lists for TCP and instead use a callout entry for each timer. - increase the TCP timer granularity to HZ - implement "bad retransmit" recovery, as presented in "On Estimating End-to-End Network Path Properties", by Allman and Paxson. Submitted by: jlemon, wollmann
1999-08-30 21:17:07 +00:00
* <sys/callout.h> defines three convenience macros:
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
*
Clarify the description of the callout_active() macro: It is cleared by callout_stop, callout_drain, and callout_deactivate, but is not automatically cleared when a callout returns.
2005-01-19 19:46:35 +00:00
* callout_active() - returns truth if callout has not been stopped,
* drained, or deactivated since the last time the callout was
* reset.
Restructure TCP timeout handling: - eliminate the fast/slow timeout lists for TCP and instead use a callout entry for each timer. - increase the TCP timer granularity to HZ - implement "bad retransmit" recovery, as presented in "On Estimating End-to-End Network Path Properties", by Allman and Paxson. Submitted by: jlemon, wollmann
1999-08-30 21:17:07 +00:00
* callout_pending() - returns truth if callout is still waiting for timeout
* callout_deactivate() - marks the callout as having been serviced
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
*/
Make callout_reset() return a non-zero value if a pending callout was rescheduled. If there was no pending callout, then return 0. Reviewed by: iedowse, cperciva
2005-09-08 14:20:39 +00:00
int
Revert the last commit to the callout interface, and add a flag to callout_init() indicating whether the callout is safe or not. Update the callers of callout_init() to reflect the new interface. Okayed by: Jake
2000-11-25 06:22:16 +00:00
callout_reset(c, to_ticks, ftn, arg)
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
struct callout *c;
int to_ticks;
Remove __P.
2002-03-19 21:25:46 +00:00
void (*ftn)(void *);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
void *arg;
{
Make callout_reset() return a non-zero value if a pending callout was rescheduled. If there was no pending callout, then return 0. Reviewed by: iedowse, cperciva
2005-09-08 14:20:39 +00:00
int cancelled = 0;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
#ifdef notyet /* Some callers of timeout() do not hold Giant. */
if (c->c_mtx != NULL)
mtx_assert(c->c_mtx, MA_OWNED);
#endif
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if (c == curr_callout) {
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
/*
* We're being asked to reschedule a callout which is
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
* currently in progress. If there is a mutex then we
* can cancel the callout if it has not really started.
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
*/
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if (c->c_mtx != NULL && !curr_cancelled)
Make callout_reset() return a non-zero value if a pending callout was rescheduled. If there was no pending callout, then return 0. Reviewed by: iedowse, cperciva
2005-09-08 14:20:39 +00:00
cancelled = curr_cancelled = 1;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if (wakeup_needed) {
/*
* Someone has called callout_drain to kill this
* callout. Don't reschedule.
*/
mtx_unlock_spin(&callout_lock);
Make callout_reset() return a non-zero value if a pending callout was rescheduled. If there was no pending callout, then return 0. Reviewed by: iedowse, cperciva
2005-09-08 14:20:39 +00:00
return (cancelled);
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
}
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
}
When reseting a pending callout, perform the deregistration in callout_reset rather than calling callout_stop. This results in a few lines of code duplication, but it provides a significant performance improvement because it avoids recursing on callout_lock. Requested by: rwatson
2004-08-06 02:44:58 +00:00
if (c->c_flags & CALLOUT_PENDING) {
if (nextsoftcheck == c) {
nextsoftcheck = TAILQ_NEXT(c, c_links.tqe);
}
TAILQ_REMOVE(&callwheel[c->c_time & callwheelmask], c,
c_links.tqe);
Make callout_reset() return a non-zero value if a pending callout was rescheduled. If there was no pending callout, then return 0. Reviewed by: iedowse, cperciva
2005-09-08 14:20:39 +00:00
cancelled = 1;
When reseting a pending callout, perform the deregistration in callout_reset rather than calling callout_stop. This results in a few lines of code duplication, but it provides a significant performance improvement because it avoids recursing on callout_lock. Requested by: rwatson
2004-08-06 02:44:58 +00:00
/*
* Part of the normal "stop a pending callout" process
* is to clear the CALLOUT_ACTIVE and CALLOUT_PENDING
* flags. We're not going to bother doing that here,
* because we're going to be setting those flags ten lines
* after this point, and we're holding callout_lock
* between now and then.
*/
}
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
/*
Axe spl's obsoleted by the callout mutex.
2001-08-10 01:36:25 +00:00
* We could unlock callout_lock here and lock it again before the
* TAILQ_INSERT_TAIL, but there's no point since doing this setup
* doesn't take much time.
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
*/
if (to_ticks <= 0)
to_ticks = 1;
c->c_arg = arg;
Revert the last commit to the callout interface, and add a flag to callout_init() indicating whether the callout is safe or not. Update the callers of callout_init() to reflect the new interface. Okayed by: Jake
2000-11-25 06:22:16 +00:00
c->c_flags |= (CALLOUT_ACTIVE | CALLOUT_PENDING);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
c->c_func = ftn;
c->c_time = ticks + to_ticks;
TAILQ_INSERT_TAIL(&callwheel[c->c_time & callwheelmask],
c, c_links.tqe);
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
Make callout_reset() return a non-zero value if a pending callout was rescheduled. If there was no pending callout, then return 0. Reviewed by: iedowse, cperciva
2005-09-08 14:20:39 +00:00
return (cancelled);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
}
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
int
_callout_stop_safe(c, safe)
struct callout *c;
int safe;
{
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
int use_mtx, wakeup_cookie;
if (!safe && c->c_mtx != NULL) {
#ifdef notyet /* Some callers do not hold Giant for Giant-locked callouts. */
mtx_assert(c->c_mtx, MA_OWNED);
use_mtx = 1;
#else
use_mtx = mtx_owned(c->c_mtx);
#endif
} else {
use_mtx = 0;
}
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
/*
* Don't attempt to delete a callout that's not on the queue.
*/
if (!(c->c_flags & CALLOUT_PENDING)) {
Restructure TCP timeout handling: - eliminate the fast/slow timeout lists for TCP and instead use a callout entry for each timer. - increase the TCP timer granularity to HZ - implement "bad retransmit" recovery, as presented in "On Estimating End-to-End Network Path Properties", by Allman and Paxson. Submitted by: jlemon, wollmann
1999-08-30 21:17:07 +00:00
c->c_flags &= ~CALLOUT_ACTIVE;
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if (c != curr_callout) {
mtx_unlock_spin(&callout_lock);
return (0);
}
if (safe) {
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
/* We need to wait until the callout is finished. */
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
wakeup_needed = 1;
wakeup_cookie = wakeup_ctr++;
mtx_unlock_spin(&callout_lock);
mtx_lock(&callout_wait_lock);
Add whitespace before comment blocks. (reported by njl) Remove spurious whitespace, add indent protection, fix punctuation, remove initialization of static variables to zero, put wakeup_ctr and wakeup_needed in the correct order. (reported by bde) This doesn't fix all the style bugs I introduced, but the remaining style bugs make it easier for me to understand what I did here.
2004-04-08 02:03:49 +00:00
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
/*
* Check to make sure that softclock() didn't
* do the wakeup in between our dropping
* callout_lock and picking up callout_wait_lock
*/
if (wakeup_cookie - wakeup_done_ctr > 0)
cv_wait(&callout_wait, &callout_wait_lock);
mtx_unlock(&callout_wait_lock);
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
} else if (use_mtx && !curr_cancelled) {
/* We can stop the callout before it runs. */
curr_cancelled = 1;
mtx_unlock_spin(&callout_lock);
return (1);
Introduce a callout_drain() function. This acts in the same manner as callout_stop(), except that if the callout being stopped is currently in progress, it blocks attempts to reset the callout and waits until the callout is completed before it returns. This makes it possible to clean up callout-using code safely, e.g., without potentially freeing memory which is still being used by a callout. Reviewed by: mux, gallatin, rwatson, jhb
2004-04-06 23:08:49 +00:00
} else
mtx_unlock_spin(&callout_lock);
Change callout_stop() to return an integer. If callout_stop() succeeds in removing the callout entry, return 1. If callout_stop() fails to remove the callout entry because it is currently executing or has already been executed, then the function returns 0. The idea was obtained from BSD/OS, however, BSD/OS changed untimeout(), and I've just changed callout_stop() to be more conservative. Obtained from: BSD/OS
2001-08-10 21:06:59 +00:00
return (0);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
}
Restructure TCP timeout handling: - eliminate the fast/slow timeout lists for TCP and instead use a callout entry for each timer. - increase the TCP timer granularity to HZ - implement "bad retransmit" recovery, as presented in "On Estimating End-to-End Network Path Properties", by Allman and Paxson. Submitted by: jlemon, wollmann
1999-08-30 21:17:07 +00:00
c->c_flags &= ~(CALLOUT_ACTIVE | CALLOUT_PENDING);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
if (nextsoftcheck == c) {
nextsoftcheck = TAILQ_NEXT(c, c_links.tqe);
}
TAILQ_REMOVE(&callwheel[c->c_time & callwheelmask], c, c_links.tqe);
if (c->c_flags & CALLOUT_LOCAL_ALLOC) {
Make "c->c_func = NULL" conditional on CALLOUT_LOCAL_ALLOC in both places where it occurs, not just one. :-) Pointed out by: glebius Pointy had to: cperciva
2005-01-19 21:15:58 +00:00
c->c_func = NULL;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
SLIST_INSERT_HEAD(&callfree, c, c_links.sle);
}
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
Change callout_stop() to return an integer. If callout_stop() succeeds in removing the callout entry, return 1. If callout_stop() fails to remove the callout entry because it is currently executing or has already been executed, then the function returns 0. The idea was obtained from BSD/OS, however, BSD/OS changed untimeout(), and I've just changed callout_stop() to be more conservative. Obtained from: BSD/OS
2001-08-10 21:06:59 +00:00
return (1);
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
}
void
Revert the last commit to the callout interface, and add a flag to callout_init() indicating whether the callout is safe or not. Update the callers of callout_init() to reflect the new interface. Okayed by: Jake
2000-11-25 06:22:16 +00:00
callout_init(c, mpsafe)
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
struct callout *c;
Revert the last commit to the callout interface, and add a flag to callout_init() indicating whether the callout is safe or not. Update the callers of callout_init() to reflect the new interface. Okayed by: Jake
2000-11-25 06:22:16 +00:00
int mpsafe;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
{
Fix callout_init(). This didn't have any practical effect since it was only used to initialize the static timeouts, which unconditionally clears the only bits which could have caused problems.
1999-03-06 22:27:02 +00:00
bzero(c, sizeof *c);
Add a mechanism for associating a mutex with a callout when the callout is first initialised, using a new function callout_init_mtx(). The callout system will acquire this mutex before calling the callout function and release it on return. In addition, the callout system uses the mutex to avoid most of the complications and race conditions inherent in asynchronous timer facilities, so mutex-protected callouts have much simpler semantics. As long as the mutex is held when invoking callout_stop() or callout_reset(), then these functions will guarantee that the callout will be stopped, even if softclock() had already begun to process the callout. Existing Giant-locked callouts will automatically pick up the new race-free semantics. This should close a number of race conditions in the USB code and probably other areas of the kernel too. There should be no change in behaviour for "MP-safe" callouts; these still need to use the techniques mentioned in timeout(9) to avoid race conditions.
2005-02-07 02:47:33 +00:00
if (mpsafe) {
c->c_mtx = NULL;
c->c_flags = CALLOUT_RETURNUNLOCKED;
} else {
c->c_mtx = &Giant;
c->c_flags = 0;
}
}
void
callout_init_mtx(c, mtx, flags)
struct callout *c;
struct mtx *mtx;
int flags;
{
bzero(c, sizeof *c);
c->c_mtx = mtx;
KASSERT((flags & ~CALLOUT_RETURNUNLOCKED) == 0,
("callout_init_mtx: bad flags %d", flags));
/* CALLOUT_RETURNUNLOCKED makes no sense without a mutex. */
KASSERT(mtx != NULL || (flags & CALLOUT_RETURNUNLOCKED) == 0,
("callout_init_mtx: CALLOUT_RETURNUNLOCKED with no mutex"));
c->c_flags = flags & CALLOUT_RETURNUNLOCKED;
Expose a slightly-lower-level interface to timeouts which allows callers to manage their own memory. Tested on my machine (make buildworld). I've made analogous changes on the alpha, but don't have a machine to test. Not-objected-to by: dg, gibbs
1999-03-06 04:46:20 +00:00
}
This patch causes the "calltodo" timer list to be decremented by the amount of time that the laptop was suspending. Thus, select() calls that might have suspended rather than firing at 1hr + "time suspended" since the timer was posted. Adding: options APM_FIXUP_CALLTODO to the kernel config enables the patch. [ This patch was slightly modified to use a consistant indent style and I removed some unused local variables. After this has been tested a few weeks we'll make the options the default, so for now I'm now documenting it in LINT. Mike can later if he wants. ] Reviewed by: Mike Smith <msmith@freebsd.org> Submitted by: Ken Key <key@cs.utk.edu>
1997-12-23 16:32:35 +00:00
#ifdef APM_FIXUP_CALLTODO
/*
* Adjust the kernel calltodo timeout list. This routine is used after
* an APM resume to recalculate the calltodo timer list values with the
* number of hz's we have been sleeping. The next hardclock() will detect
* that there are fired timers and run softclock() to execute them.
*
* Please note, I have not done an exhaustive analysis of what code this
* might break. I am motivated to have my select()'s and alarm()'s that
* have expired during suspend firing upon resume so that the applications
* which set the timer can do the maintanence the timer was for as close
* as possible to the originally intended time. Testing this code for a
* week showed that resuming from a suspend resulted in 22 to 25 timers
* firing, which seemed independant on whether the suspend was 2 hours or
* 2 days. Your milage may vary. - Ken Key <key@cs.utk.edu>
*/
void
adjust_timeout_calltodo(time_change)
struct timeval *time_change;
{
register struct callout *p;
unsigned long delta_ticks;
/*
* How many ticks were we asleep?
Fixed stale references to hzto() in comments.
1998-05-17 20:08:05 +00:00
* (stolen from tvtohz()).
This patch causes the "calltodo" timer list to be decremented by the amount of time that the laptop was suspending. Thus, select() calls that might have suspended rather than firing at 1hr + "time suspended" since the timer was posted. Adding: options APM_FIXUP_CALLTODO to the kernel config enables the patch. [ This patch was slightly modified to use a consistant indent style and I removed some unused local variables. After this has been tested a few weeks we'll make the options the default, so for now I'm now documenting it in LINT. Mike can later if he wants. ] Reviewed by: Mike Smith <msmith@freebsd.org> Submitted by: Ken Key <key@cs.utk.edu>
1997-12-23 16:32:35 +00:00
*/
/* Don't do anything */
if (time_change->tv_sec < 0)
return;
else if (time_change->tv_sec <= LONG_MAX / 1000000)
delta_ticks = (time_change->tv_sec * 1000000 +
time_change->tv_usec + (tick - 1)) / tick + 1;
else if (time_change->tv_sec <= LONG_MAX / hz)
delta_ticks = time_change->tv_sec * hz +
(time_change->tv_usec + (tick - 1)) / tick + 1;
else
delta_ticks = LONG_MAX;
if (delta_ticks > INT_MAX)
delta_ticks = INT_MAX;
/*
* Now rip through the timer calltodo list looking for timers
* to expire.
*/
/* don't collide with softclock() */
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&callout_lock);
This patch causes the "calltodo" timer list to be decremented by the amount of time that the laptop was suspending. Thus, select() calls that might have suspended rather than firing at 1hr + "time suspended" since the timer was posted. Adding: options APM_FIXUP_CALLTODO to the kernel config enables the patch. [ This patch was slightly modified to use a consistant indent style and I removed some unused local variables. After this has been tested a few weeks we'll make the options the default, so for now I'm now documenting it in LINT. Mike can later if he wants. ] Reviewed by: Mike Smith <msmith@freebsd.org> Submitted by: Ken Key <key@cs.utk.edu>
1997-12-23 16:32:35 +00:00
for (p = calltodo.c_next; p != NULL; p = p->c_next) {
p->c_time -= delta_ticks;
/* Break if the timer had more time on it than delta_ticks */
if (p->c_time > 0)
break;
/* take back the ticks the timer didn't use (p->c_time <= 0) */
delta_ticks = -p->c_time;
}
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&callout_lock);
This patch causes the "calltodo" timer list to be decremented by the amount of time that the laptop was suspending. Thus, select() calls that might have suspended rather than firing at 1hr + "time suspended" since the timer was posted. Adding: options APM_FIXUP_CALLTODO to the kernel config enables the patch. [ This patch was slightly modified to use a consistant indent style and I removed some unused local variables. After this has been tested a few weeks we'll make the options the default, so for now I'm now documenting it in LINT. Mike can later if he wants. ] Reviewed by: Mike Smith <msmith@freebsd.org> Submitted by: Ken Key <key@cs.utk.edu>
1997-12-23 16:32:35 +00:00
return;
}
#endif /* APM_FIXUP_CALLTODO */
Reference in New Issue Copy Permalink