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freebsd-dev/sys/kern/kern_idle.c

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Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
/*-
Expand the generic, but bogusly formed, copyright notice to include the license from /usr/src/COPYRIGHT. Since cvs annotate shows that this was written by jasone, julian, jhb, peter, bmilekic and obrien. cvs log shows that many others may have contributed to this file. As such, go ahead and use the author of 'FreeBSD Project' for this file. If this is a problem, please notify me. # this eliminates the last file in the kernel with an indirect reference # to /usr/src/COPYRIGHT in the kernel. A few more in userland remain.
2004-07-25 19:49:01 +00:00
* Copyright (C) 2000-2004 The FreeBSD Project. All rights reserved.
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
*
Expand the generic, but bogusly formed, copyright notice to include the license from /usr/src/COPYRIGHT. Since cvs annotate shows that this was written by jasone, julian, jhb, peter, bmilekic and obrien. cvs log shows that many others may have contributed to this file. As such, go ahead and use the author of 'FreeBSD Project' for this file. If this is a problem, please notify me. # this eliminates the last file in the kernel with an indirect reference # to /usr/src/COPYRIGHT in the kernel. A few more in userland remain.
2004-07-25 19:49:01 +00:00
* 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.
*
* THIS SOFTWARE IS PROVIDED BY AUTHOR 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 AUTHOR 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.
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
*/
Use __FBSDID().
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
- Split out the support for per-CPU data from the SMP code. UP kernels have per-CPU data and gdb on the i386 at least needs access to it. - Clean up includes in kern_idle.c and subr_smp.c. Reviewed by: jake
2001-05-10 17:45:49 +00:00
#include <sys/kthread.h>
Undo part of the tangle of having sys/lock.h and sys/mutex.h included in other "system" header files. Also help the deprecation of lockmgr.h by making it a sub-include of sys/lock.h and removing sys/lockmgr.h form kernel .c files. Sort sys/*.h includes where possible in affected files. OK'ed by: bde (with reservations)
2001-05-01 08:13:21 +00:00
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#include <sys/resourcevar.h>
- Create a new scheduler api that is defined in sys/sched.h - Begin moving scheduler specific functionality into sched_4bsd.c - Replace direct manipulation of scheduler data with hooks provided by the new api. - Remove KSE specific state modifications and single runq assumptions from kern_switch.c Reviewed by: -arch
2002-10-12 05:32:24 +00:00
#include <sys/sched.h>
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#include <sys/unistd.h>
Give the 4bsd scheduler the ability to wake up idle processors when there is new work to be done. MFC after: 5 days
2004-09-01 06:42:02 +00:00
#ifdef SMP
#include <sys/smp.h>
#endif
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
static void idle_setup(void *dummy);
In keeping with style(9)'s recommendations on macros, use a ';' after each SYSINIT() macro invocation. This makes a number of lightweight C parsers much happier with the FreeBSD kernel source, including cflow's prcc and lxr. MFC after: 1 month Discussed with: imp, rink
2008-03-16 10:58:09 +00:00
SYSINIT(idle_setup, SI_SUB_SCHED_IDLE, SI_ORDER_FIRST, idle_setup, NULL);
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
/*
Tidy up loose ends in the idle process. Call the MI cpu_idle() function for all platforms now. XXX alpha/sparc64/powerpc should fill in the function. Submitted by: bde
2003-10-19 02:43:57 +00:00
* Set up per-cpu idle process contexts. The AP's shouldn't be running or
- Point out that we don't lock anything during the idle setup because only the boot processor should be running in the comments. - Initialize curproc to point to each CPU's respective idleproc if their curproc is NULL. - Keep track of the number of context switches performed by idleproc.
2001-02-09 14:59:43 +00:00
* accessing their idle processes at this point, so don't bother with
* locking.
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
*/
static void
idle_setup(void *dummy)
{
Overhaul of the SMP code. Several portions of the SMP kernel support have been made machine independent and various other adjustments have been made to support Alpha SMP. - It splits the per-process portions of hardclock() and statclock() off into hardclock_process() and statclock_process() respectively. hardclock() and statclock() call the *_process() functions for the current process so that UP systems will run as before. For SMP systems, it is simply necessary to ensure that all other processors execute the *_process() functions when the main clock functions are triggered on one CPU by an interrupt. For the alpha 4100, clock interrupts are delievered in a staggered broadcast fashion, so we simply call hardclock/statclock on the boot CPU and call the *_process() functions on the secondaries. For x86, we call statclock and hardclock as usual and then call forward_hardclock/statclock in the MD code to send an IPI to cause the AP's to execute forwared_hardclock/statclock which then call the *_process() functions. - forward_signal() and forward_roundrobin() have been reworked to be MI and to involve less hackery. Now the cpu doing the forward sets any flags, etc. and sends a very simple IPI_AST to the other cpu(s). AST IPIs now just basically return so that they can execute ast() and don't bother with setting the astpending or needresched flags themselves. This also removes the loop in forward_signal() as sched_lock closes the race condition that the loop worked around. - need_resched(), resched_wanted() and clear_resched() have been changed to take a process to act on rather than assuming curproc so that they can be used to implement forward_roundrobin() as described above. - Various other SMP variables have been moved to a MI subr_smp.c and a new header sys/smp.h declares MI SMP variables and API's. The IPI API's from machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h. - The globaldata_register() and globaldata_find() functions as well as the SLIST of globaldata structures has become MI and moved into subr_smp.c. Also, the globaldata list is only available if SMP support is compiled in. Reviewed by: jake, peter Looked over by: eivind
2001-04-27 19:28:25 +00:00
#ifdef SMP
Overhaul the per-CPU support a bit: - The MI portions of struct globaldata have been consolidated into a MI struct pcpu. The MD per-CPU data are specified via a macro defined in machine/pcpu.h. A macro was chosen over a struct mdpcpu so that the interface would be cleaner (PCPU_GET(my_md_field) vs. PCPU_GET(md.md_my_md_field)). - All references to globaldata are changed to pcpu instead. In a UP kernel, this data was stored as global variables which is where the original name came from. In an SMP world this data is per-CPU and ideally private to each CPU outside of the context of debuggers. This also included combining machine/globaldata.h and machine/globals.h into machine/pcpu.h. - The pointer to the thread using the FPU on i386 was renamed from npxthread to fpcurthread to be identical with other architectures. - Make the show pcpu ddb command MI with a MD callout to display MD fields. - The globaldata_register() function was renamed to pcpu_init() and now init's MI fields of a struct pcpu in addition to registering it with the internal array and list. - A pcpu_destroy() function was added to remove a struct pcpu from the internal array and list. Tested on: alpha, i386 Reviewed by: peter, jake
2001-12-11 23:33:44 +00:00
struct pcpu *pc;
Overhaul of the SMP code. Several portions of the SMP kernel support have been made machine independent and various other adjustments have been made to support Alpha SMP. - It splits the per-process portions of hardclock() and statclock() off into hardclock_process() and statclock_process() respectively. hardclock() and statclock() call the *_process() functions for the current process so that UP systems will run as before. For SMP systems, it is simply necessary to ensure that all other processors execute the *_process() functions when the main clock functions are triggered on one CPU by an interrupt. For the alpha 4100, clock interrupts are delievered in a staggered broadcast fashion, so we simply call hardclock/statclock on the boot CPU and call the *_process() functions on the secondaries. For x86, we call statclock and hardclock as usual and then call forward_hardclock/statclock in the MD code to send an IPI to cause the AP's to execute forwared_hardclock/statclock which then call the *_process() functions. - forward_signal() and forward_roundrobin() have been reworked to be MI and to involve less hackery. Now the cpu doing the forward sets any flags, etc. and sends a very simple IPI_AST to the other cpu(s). AST IPIs now just basically return so that they can execute ast() and don't bother with setting the astpending or needresched flags themselves. This also removes the loop in forward_signal() as sched_lock closes the race condition that the loop worked around. - need_resched(), resched_wanted() and clear_resched() have been changed to take a process to act on rather than assuming curproc so that they can be used to implement forward_roundrobin() as described above. - Various other SMP variables have been moved to a MI subr_smp.c and a new header sys/smp.h declares MI SMP variables and API's. The IPI API's from machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h. - The globaldata_register() and globaldata_find() functions as well as the SLIST of globaldata structures has become MI and moved into subr_smp.c. Also, the globaldata list is only available if SMP support is compiled in. Reviewed by: jake, peter Looked over by: eivind
2001-04-27 19:28:25 +00:00
#endif
struct proc *p;
Part 1 of KSE-III The ability to schedule multiple threads per process (one one cpu) by making ALL system calls optionally asynchronous. to come: ia64 and power-pc patches, patches for gdb, test program (in tools) Reviewed by: Almost everyone who counts (at various times, peter, jhb, matt, alfred, mini, bernd, and a cast of thousands) NOTE: this is still Beta code, and contains lots of debugging stuff. expect slight instability in signals..
2002-06-29 17:26:22 +00:00
struct thread *td;
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
int error;
Initialise the initial process pointer to NULL so that we know we don't have an idle process yet. I'm guessing that on my system this was always 0 already. found by: Ed Schouten
2007-10-27 00:42:40 +00:00
p = NULL; /* start with no idle process */
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#ifdef SMP
On multi-core, multi-threaded PPC systems, it is important that the threads be brought up in the order they are enumerated in the device tree (in particular, that thread 0 on each core be brought up first). The SLIST through which we loop to start the CPUs has all of its entries added with SLIST_INSERT_HEAD(), which means it is in reverse order of enumeration and so AP startup would always fail in such situations (causing a machine check or RTAS failure). Fix this by changing the SLIST into an STAILQ, and inserting new CPUs at the end. Reviewed by: jhb
2011-05-31 15:11:43 +00:00
STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
Introduce a way to make pure kernal threads. kthread_add() takes the same parameters as the old kthread_create() plus a pointer to a process structure, and adds a kernel thread to that process. kproc_kthread_add() takes the parameters for kthread_add, plus a process name and a pointer to a pointer to a process instead of just a pointer, and if the proc * is NULL, it creates the process to the specifications required, before adding the thread to it. All other old kthread_xxx() calls return, but act on (struct thread *) instead of (struct proc *). One reason to change the name is so that any old kernel modules that are lying around and expect kthread_create() to make a process will not just accidentally link. fix top to show kernel threads by their thread name in -SH mode add a tdnam formatting option to ps to show thread names. make all idle threads actual kthreads and put them into their own idled process. make all interrupt threads kthreads and put them in an interd process (mainly for aesthetic and accounting reasons) rename proc 0 to be 'kernel' and it's swapper thread is now 'swapper' man page fixes to follow.
2007-10-26 08:00:41 +00:00
#endif
oops, over optimised and broke non-SMP builds
2007-10-26 20:32:33 +00:00
#ifdef SMP
Introduce a way to make pure kernal threads. kthread_add() takes the same parameters as the old kthread_create() plus a pointer to a process structure, and adds a kernel thread to that process. kproc_kthread_add() takes the parameters for kthread_add, plus a process name and a pointer to a pointer to a process instead of just a pointer, and if the proc * is NULL, it creates the process to the specifications required, before adding the thread to it. All other old kthread_xxx() calls return, but act on (struct thread *) instead of (struct proc *). One reason to change the name is so that any old kernel modules that are lying around and expect kthread_create() to make a process will not just accidentally link. fix top to show kernel threads by their thread name in -SH mode add a tdnam formatting option to ps to show thread names. make all idle threads actual kthreads and put them into their own idled process. make all interrupt threads kthreads and put them in an interd process (mainly for aesthetic and accounting reasons) rename proc 0 to be 'kernel' and it's swapper thread is now 'swapper' man page fixes to follow.
2007-10-26 08:00:41 +00:00
error = kproc_kthread_add(sched_idletd, NULL, &p, &td,
rename the process to 'idle' and 'intr' as per jhb.
2007-10-27 00:52:26 +00:00
RFSTOPPED | RFHIGHPID, 0, "idle", "idle: cpu%d", pc->pc_cpuid);
Introduce a way to make pure kernal threads. kthread_add() takes the same parameters as the old kthread_create() plus a pointer to a process structure, and adds a kernel thread to that process. kproc_kthread_add() takes the parameters for kthread_add, plus a process name and a pointer to a pointer to a process instead of just a pointer, and if the proc * is NULL, it creates the process to the specifications required, before adding the thread to it. All other old kthread_xxx() calls return, but act on (struct thread *) instead of (struct proc *). One reason to change the name is so that any old kernel modules that are lying around and expect kthread_create() to make a process will not just accidentally link. fix top to show kernel threads by their thread name in -SH mode add a tdnam formatting option to ps to show thread names. make all idle threads actual kthreads and put them into their own idled process. make all interrupt threads kthreads and put them in an interd process (mainly for aesthetic and accounting reasons) rename proc 0 to be 'kernel' and it's swapper thread is now 'swapper' man page fixes to follow.
2007-10-26 08:00:41 +00:00
pc->pc_idlethread = td;
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#else
oops, over optimised and broke non-SMP builds
2007-10-26 20:32:33 +00:00
error = kproc_kthread_add(sched_idletd, NULL, &p, &td,
rename the process to 'idle' and 'intr' as per jhb.
2007-10-27 00:52:26 +00:00
RFSTOPPED | RFHIGHPID, 0, "idle", "idle");
Introduce a way to make pure kernal threads. kthread_add() takes the same parameters as the old kthread_create() plus a pointer to a process structure, and adds a kernel thread to that process. kproc_kthread_add() takes the parameters for kthread_add, plus a process name and a pointer to a pointer to a process instead of just a pointer, and if the proc * is NULL, it creates the process to the specifications required, before adding the thread to it. All other old kthread_xxx() calls return, but act on (struct thread *) instead of (struct proc *). One reason to change the name is so that any old kernel modules that are lying around and expect kthread_create() to make a process will not just accidentally link. fix top to show kernel threads by their thread name in -SH mode add a tdnam formatting option to ps to show thread names. make all idle threads actual kthreads and put them into their own idled process. make all interrupt threads kthreads and put them in an interd process (mainly for aesthetic and accounting reasons) rename proc 0 to be 'kernel' and it's swapper thread is now 'swapper' man page fixes to follow.
2007-10-26 08:00:41 +00:00
PCPU_SET(idlethread, td);
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
#endif
if (error)
Rename the kthread_xxx (e.g. kthread_create()) calls to kproc_xxx as they actually make whole processes. Thos makes way for us to add REAL kthread_create() and friends that actually make theads. it turns out that most of these calls actually end up being moved back to the thread version when it's added. but we need to make this cosmetic change first. I'd LOVE to do this rename in 7.0 so that we can eventually MFC the new kthread_xxx() calls.
2007-10-20 23:23:23 +00:00
panic("idle_setup: kproc_create error %d\n", error);
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
Commit 14/14 of sched_lock decomposition. - Use thread_lock() rather than sched_lock for per-thread scheduling sychronization. - Use the per-process spinlock rather than the sched_lock for per-process scheduling synchronization. Tested by: kris, current@ Tested on: i386, amd64, ULE, 4BSD, libthr, libkse, PREEMPTION, etc. Discussed with: kris, attilio, kmacy, jhb, julian, bde (small parts each)
2007-06-05 00:00:57 +00:00
thread_lock(td);
- Change mi_switch() and sched_switch() to accept an optional thread to switch to. If a non-NULL thread pointer is passed in, then the CPU will switch to that thread directly rather than calling choosethread() to pick a thread to choose to. - Make sched_switch() aware of idle threads and know to do TD_SET_CAN_RUN() instead of sticking them on the run queue rather than requiring all callers of mi_switch() to know to do this if they can be called from an idlethread. - Move constants for arguments to mi_switch() and thread_single() out of the middle of the function prototypes and up above into their own section.
2004-07-02 19:09:50 +00:00
TD_SET_CAN_RUN(td);
Split P_NOLOAD into a per-thread flag (TDF_NOLOAD). This improvements aims for avoiding further cache-misses in scheduler specific functions which need to keep track of average thread running time and further locking in places setting for this flag. Reported by: jeff (originally), kris (currently) Reviewed by: jhb Tested by: Giuseppe Cocomazzi <sbudella at email dot it>
2009-11-03 16:46:52 +00:00
td->td_flags |= TDF_IDLETD | TDF_NOLOAD;
Make KSE a kernel option, turned on by default in all GENERIC kernel configs except sun4v (which doesn't process signals properly with KSE). Reviewed by: davidxu@
2006-10-26 21:42:22 +00:00
sched_class(td, PRI_IDLE);
Set the scheduling class of the idle threads to PRI_IDLE. While there, set their priority with sched_prio() instead of changing it 'by hand'. Reviewed by: jhb Approved by: grehan (mentor)
2005-02-04 06:16:05 +00:00
sched_prio(td, PRI_MAX_IDLE);
Commit 14/14 of sched_lock decomposition. - Use thread_lock() rather than sched_lock for per-thread scheduling sychronization. - Use the per-process spinlock rather than the sched_lock for per-process scheduling synchronization. Tested by: kris, current@ Tested on: i386, amd64, ULE, 4BSD, libthr, libkse, PREEMPTION, etc. Discussed with: kris, attilio, kmacy, jhb, julian, bde (small parts each)
2007-06-05 00:00:57 +00:00
thread_unlock(td);
Overhaul of the SMP code. Several portions of the SMP kernel support have been made machine independent and various other adjustments have been made to support Alpha SMP. - It splits the per-process portions of hardclock() and statclock() off into hardclock_process() and statclock_process() respectively. hardclock() and statclock() call the *_process() functions for the current process so that UP systems will run as before. For SMP systems, it is simply necessary to ensure that all other processors execute the *_process() functions when the main clock functions are triggered on one CPU by an interrupt. For the alpha 4100, clock interrupts are delievered in a staggered broadcast fashion, so we simply call hardclock/statclock on the boot CPU and call the *_process() functions on the secondaries. For x86, we call statclock and hardclock as usual and then call forward_hardclock/statclock in the MD code to send an IPI to cause the AP's to execute forwared_hardclock/statclock which then call the *_process() functions. - forward_signal() and forward_roundrobin() have been reworked to be MI and to involve less hackery. Now the cpu doing the forward sets any flags, etc. and sends a very simple IPI_AST to the other cpu(s). AST IPIs now just basically return so that they can execute ast() and don't bother with setting the astpending or needresched flags themselves. This also removes the loop in forward_signal() as sched_lock closes the race condition that the loop worked around. - need_resched(), resched_wanted() and clear_resched() have been changed to take a process to act on rather than assuming curproc so that they can be used to implement forward_roundrobin() as described above. - Various other SMP variables have been moved to a MI subr_smp.c and a new header sys/smp.h declares MI SMP variables and API's. The IPI API's from machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h. - The globaldata_register() and globaldata_find() functions as well as the SLIST of globaldata structures has become MI and moved into subr_smp.c. Also, the globaldata list is only available if SMP support is compiled in. Reviewed by: jake, peter Looked over by: eivind
2001-04-27 19:28:25 +00:00
#ifdef SMP
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
}
Overhaul of the SMP code. Several portions of the SMP kernel support have been made machine independent and various other adjustments have been made to support Alpha SMP. - It splits the per-process portions of hardclock() and statclock() off into hardclock_process() and statclock_process() respectively. hardclock() and statclock() call the *_process() functions for the current process so that UP systems will run as before. For SMP systems, it is simply necessary to ensure that all other processors execute the *_process() functions when the main clock functions are triggered on one CPU by an interrupt. For the alpha 4100, clock interrupts are delievered in a staggered broadcast fashion, so we simply call hardclock/statclock on the boot CPU and call the *_process() functions on the secondaries. For x86, we call statclock and hardclock as usual and then call forward_hardclock/statclock in the MD code to send an IPI to cause the AP's to execute forwared_hardclock/statclock which then call the *_process() functions. - forward_signal() and forward_roundrobin() have been reworked to be MI and to involve less hackery. Now the cpu doing the forward sets any flags, etc. and sends a very simple IPI_AST to the other cpu(s). AST IPIs now just basically return so that they can execute ast() and don't bother with setting the astpending or needresched flags themselves. This also removes the loop in forward_signal() as sched_lock closes the race condition that the loop worked around. - need_resched(), resched_wanted() and clear_resched() have been changed to take a process to act on rather than assuming curproc so that they can be used to implement forward_roundrobin() as described above. - Various other SMP variables have been moved to a MI subr_smp.c and a new header sys/smp.h declares MI SMP variables and API's. The IPI API's from machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h. - The globaldata_register() and globaldata_find() functions as well as the SLIST of globaldata structures has become MI and moved into subr_smp.c. Also, the globaldata list is only available if SMP support is compiled in. Reviewed by: jake, peter Looked over by: eivind
2001-04-27 19:28:25 +00:00
#endif
Major update to the way synchronization is done in the kernel. Highlights include: * Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The alpha port is still in transition and currently uses both.) * Per-CPU idle processes. * Interrupts are run in their own separate kernel threads and can be preempted (i386 only). Partially contributed by: BSDi (BSD/OS) Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
}
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