Commit Graph

91 Commits

Author SHA1 Message Date
John Baldwin
9b4982bfed Add a WITNESS_WARN() call to verify that we hold no locks after running
a handler from an interrupt thread.
2003-03-04 21:01:42 +00:00
Warner Losh
a163d034fa Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
Julian Elischer
4a338afd7a Move a bunch of flags from the KSE to the thread.
I was in two minds as to where to put them in the first case..
I should have listenned to the other mind.

Submitted by:	 parts by davidxu@
Reviewed by:	jeff@ mini@
2003-02-17 09:55:10 +00:00
Alfred Perlstein
c11110eabe Fix crash dumps on ata and scsi.
To fix scsi, don't wait for ithreads if we're dumping, it makes the
debugger sad.

To fix ata, use what appears to be a polling method if we're dumping,
I stole this from tmm but added code to ensure that this change is
only in effect while dumping.

Tested by: des
2003-02-14 13:10:40 +00:00
Alfred Perlstein
44956c9863 Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
Jake Burkholder
24fbeaf9c3 Don't put a newline in KTR traces. 2002-12-28 23:22:22 +00:00
Robert Drehmel
bb8992b32c Instead of (sizeof(source_buffer) - 1) bytes, copy at most
(sizeof(destination_buffer) - 1) bytes into the destination buffer.
This was not harmful because they currently both provide space for
(MAXCOMLEN + 1) bytes.
2002-10-17 21:02:02 +00:00
Robert Drehmel
e80fb43467 Use strlcpy() instead of strncpy() to copy NUL terminated strings
for safety and consistency.
2002-10-17 20:03:38 +00:00
Scott Long
316ec49abd Some kernel threads try to do significant work, and the default KSTACK_PAGES
doesn't give them enough stack to do much before blowing away the pcb.
This adds MI and MD code to allow the allocation of an alternate kstack
who's size can be speficied when calling kthread_create.  Passing the
value 0 prevents the alternate kstack from being created.  Note that the
ia64 MD code is missing for now, and PowerPC was only partially written
due to the pmap.c being incomplete there.
Though this patch does not modify anything to make use of the alternate
kstack, acpi and usb are good candidates.

Reviewed by:	jake, peter, jhb
2002-10-02 07:44:29 +00:00
Poul-Henning Kamp
37c841831f Be consistent about "static" functions: if the function is marked
static in its prototype, mark it static at the definition too.

Inspired by:    FlexeLint warning #512
2002-09-28 17:15:38 +00:00
Jake Burkholder
98f93c07a5 Removed unneeded include (missed in last revision). 2002-09-22 06:05:23 +00:00
Jake Burkholder
e3b6e33c07 Moved netisr code from kern/kern_intr.c to net/netisr.c as threatened in a
comment.
2002-09-22 05:56:41 +00:00
Julian Elischer
71fad9fdee Completely redo thread states.
Reviewed by:	davidxu@freebsd.org
2002-09-11 08:13:56 +00:00
David Xu
65c17e749b Remove extra ';' 2002-09-06 00:18:52 +00:00
Julian Elischer
04774f2357 Slight cleanup of some comments/whitespace.
Make idle process state more consistant.
Add an assert on thread state.
Clean up idleproc/mi_switch() interaction.
Use a local instead of referencing curthread 7 times in a row
(I've been told curthread can be expensive on some architectures)
Remove some commented out code.
Add a little commented out code (completion coming soon)

Reviewed by:	jhb@freebsd.org
2002-08-01 18:45:10 +00:00
Julian Elischer
e602ba25fd 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
Julian Elischer
2d0231f5da diff reduction from KSE to keep WW-III from happenning on -current 2002-05-29 20:40:50 +00:00
John Baldwin
b106d2f56a - Set the base priority of an ithread that has no handlers when we set its
normal priority.
- Lock sched_lock while we dink with the priorities.
- Remove a few extra blank lines.
2002-04-11 21:03:35 +00:00
John Baldwin
2b60cfc5ce Don't lock the ithread lock in ithread_create(). The ithread isn't on any
lists or in any tables yet so there are no other references to it, thus
we don't need to lock it.
2002-04-09 16:26:37 +00:00
John Baldwin
6008862bc2 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
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
Luigi Rizzo
2dbd9d5bc3 Make the DEVICE_POLLING code compile with -Werror and in LINT 2002-03-09 08:02:52 +00:00
Luigi Rizzo
daccb6386b MFS: synchronize the code with the version in -stable, specifically:
+ SYSCTL_ULONG -> SYSCTL_UINT
 + some procedure renaming and variable rearrangement
 + fix the 'interface going deaf' problem same as in -stable.
2002-02-11 23:56:18 +00:00
Julian Elischer
2c1007663f In a threaded world, differnt priorirites become properties of
different entities.  Make it so.

Reviewed by:	jhb@freebsd.org (john baldwin)
2002-02-11 20:37:54 +00:00
Julian Elischer
079b7badea Pre-KSE/M3 commit.
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.

Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
2002-02-07 20:58:47 +00:00
John Baldwin
c86b6ff551 Change the preemption code for software interrupt thread schedules and
mutex releases to not require flags for the cases when preemption is
not allowed:

The purpose of the MTX_NOSWITCH and SWI_NOSWITCH flags is to prevent
switching to a higher priority thread on mutex releease and swi schedule,
respectively when that switch is not safe.  Now that the critical section
API maintains a per-thread nesting count, the kernel can easily check
whether or not it should switch without relying on flags from the
programmer.  This fixes a few bugs in that all current callers of
swi_sched() used SWI_NOSWITCH, when in fact, only the ones called from
fast interrupt handlers and the swi_sched of softclock needed this flag.
Note that to ensure that swi_sched()'s in clock and fast interrupt
handlers do not switch, these handlers have to be explicitly wrapped
in critical_enter/exit pairs.  Presently, just wrapping the handlers is
sufficient, but in the future with the fully preemptive kernel, the
interrupt must be EOI'd before critical_exit() is called.  (critical_exit()
can switch due to a deferred preemption in a fully preemptive kernel.)

I've tested the changes to the interrupt code on i386 and alpha.  I have
not tested ia64, but the interrupt code is almost identical to the alpha
code, so I expect it will work fine.  PowerPC and ARM do not yet have
interrupt code in the tree so they shouldn't be broken.  Sparc64 is
broken, but that's been ok'd by jake and tmm who will be fixing the
interrupt code for sparc64 shortly.

Reviewed by:	peter
Tested on:	i386, alpha
2002-01-05 08:47:13 +00:00
Luigi Rizzo
e4fc250c15 Device Polling code for -current.
Non-SMP, i386-only, no polling in the idle loop at the moment.

To use this code you must compile a kernel with

        options DEVICE_POLLING

and at runtime enable polling with

        sysctl kern.polling.enable=1

The percentage of CPU reserved to userland can be set with

        sysctl kern.polling.user_frac=NN (default is 50)

while the remainder is used by polling device drivers and netisr's.
These are the only two variables that you should need to touch. There
are a few more parameters in kern.polling but the default values
are adequate for all purposes. See the code in kern_poll.c for
more details on them.

Polling in the idle loop will be implemented shortly by introducing
a kernel thread which does the job. Until then, the amount of CPU
dedicated to polling will never exceed (100-user_frac).
The equivalent (actually, better) code for -stable is at

	http://info.iet.unipi.it/~luigi/polling/

and also supports polling in the idle loop.

NOTE to Alpha developers:
There is really nothing in this code that is i386-specific.
If you move the 2 lines supporting the new option from
sys/conf/{files,options}.i386 to sys/conf/{files,options} I am
pretty sure that this should work on the Alpha as well, just that
I do not have a suitable test box to try it. If someone feels like
trying it, I would appreciate it.

NOTE to other developers:
sure some things could be done better, and as always I am open to
constructive criticism, which a few of you have already given and
I greatly appreciated.
However, before proposing radical architectural changes, please
take some time to possibly try out this code, or at the very least
read the comments in kern_poll.c, especially re. the reason why I
am using a soft netisr and cannot (I believe) replace it with a
simple timeout.

Quick description of files touched by this commit:

sys/conf/files.i386
        new file kern/kern_poll.c
sys/conf/options.i386
        new option
sys/i386/i386/trap.c
        poll in trap (disabled by default)
sys/kern/kern_clock.c
        initialization and hardclock hooks.
sys/kern/kern_intr.c
        minor swi_net changes
sys/kern/kern_poll.c
        the bulk of the code.
sys/net/if.h
        new flag
sys/net/if_var.h
        declaration for functions used in device drivers.
sys/net/netisr.h
        NETISR_POLL
sys/dev/fxp/if_fxp.c
sys/dev/fxp/if_fxpvar.h
sys/pci/if_dc.c
sys/pci/if_dcreg.h
sys/pci/if_sis.c
sys/pci/if_sisreg.h
        device driver modifications
2001-12-14 17:56:12 +00:00
David E. O'Brien
91f9161737 Repeat after me -- "Use of ANSI string concatenation can be bad."
In this case, C99's __func__ is properly defined as:

	static const char __func__[] = "function-name";

and GCC 3.1 will not allow it to be used in bogus string concatenation.
2001-12-10 05:40:12 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00
David E. O'Brien
6533ba2e33 Match the declaration in net/netisr.h.
Submitted by:	gcc 3.0.1
2001-09-03 03:24:31 +00:00
John Baldwin
688ebe120c - Close races with signals and other AST's being triggered while we are in
the process of exiting the kernel.  The ast() function now loops as long
  as the PS_ASTPENDING or PS_NEEDRESCHED flags are set.  It returns with
  preemption disabled so that any further AST's that arrive via an
  interrupt will be delayed until the low-level MD code returns to user
  mode.
- Use u_int's to store the tick counts for profiling purposes so that we
  do not need sched_lock just to read p_sticks.  This also closes a
  problem where the call to addupc_task() could screw up the arithmetic
  due to non-atomic reads of p_sticks.
- Axe need_proftick(), aston(), astoff(), astpending(), need_resched(),
  clear_resched(), and resched_wanted() in favor of direct bit operations
  on p_sflag.
- Fix up locking with sched_lock some.  In addupc_intr(), use sched_lock
  to ensure pr_addr and pr_ticks are updated atomically with setting
  PS_OWEUPC.  In ast() we clear pr_ticks atomically with clearing
  PS_OWEUPC.  We also do not grab the lock just to test a flag.
- Simplify the handling of Giant in ast() slightly.

Reviewed by:	bde (mostly)
2001-08-10 22:53:32 +00:00
John Baldwin
a300519d41 Make the schedlock saved critical section state a per-thread property. 2001-06-30 03:11:26 +00:00
John Baldwin
84bbc4dbda Count the switch when an ithread goes idle as a voluntary context switch.
Submitted by:	bde
2001-06-25 18:27:33 +00:00
John Baldwin
2e1aacccac Preemption by an interrupt thread is an involuntary switch, not a voluntary
one.

Pointy-hat to:	me
2001-06-20 18:26:41 +00:00
Peter Wemm
5a280d9cd1 Add INTR_TYPE_AV so that we can get to the PI_AV priority in the ithread
handlers.  This is beneficial since it means that pcm's MPSAFE handler
can get run before things that will block on Giant in the shared irq
case.
2001-06-16 22:42:19 +00:00
Thomas Moestl
d279178df7 Clean up the code exporting interrupt statistics via sysctl a bit:
- move the sysctl code to kern_intr.c
- do not use INTRCNT_COUNT, but rather eintrcnt - intrcnt to determine
  the length of the intrcnt array
- move the declarations of intrnames, eintrnames, intrcnt and eintrcnt
  from machine-dependent include files to sys/interrupt.h
- remove the hw.nintr sysctl, it is not needed.
- fix various style bugs

Requested by:	bde
Reviewed by:	bde (some time ago)
2001-06-01 13:23:28 +00:00
John Baldwin
4d29cb2db9 - Remove the global ithread_list_lock spin lock in favor of per-ithread
sleep locks.
- Delay returning from ithread_remove_handler() until we are certain that
  the interrupt handler being removed has in fact been removed from the
  ithread.
- XXX: There is still a problem in that nothing protects the kernel from
  adding a new handler while the ithread is running, though with our
  current architectures this is not a problem.

Requested by:	gibbs (2)
2001-05-17 22:43:26 +00:00
John Baldwin
8bd57f8fc2 Remove unneeded includes of sys/ipl.h and machine/ipl.h. 2001-05-15 23:22:29 +00:00
John Baldwin
6caa8a1501 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
John Baldwin
f34fa851e0 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
John Baldwin
b944b9033a Catch up to the mtx_saveintr -> mtx_savecrit change. 2001-03-28 02:46:21 +00:00
John Baldwin
1f723035c8 Use (..., "%s", foo) instead of (..., foo) to avoid a warning about a
non-constant format string when calling kthread_create() to create an
ithread.
2001-03-24 06:26:47 +00:00
John Baldwin
003fb9ec2f Ok, the kernel will panic in kmem_malloc() if the kernel map is full, so
malloc with M_WAITOK can't actually return NULL.  I wish I could get two
people to give me the same answer about this when I ask...

Submitted by:	jake
2001-03-02 06:07:38 +00:00
John Baldwin
653dd8c243 - Check to see if malloc() returned NULL even with M_WAITOK.
- Add a KASSERT() to ensure an ithread has a backing kernel thread when we
  schedule it.
- Don't attempt to preemptively switch to an ithread if p_stat of curproc
  is not SRUN.
2001-03-02 05:33:03 +00:00
Jake Burkholder
5b270b2a55 Sigh. Try to get priorities sorted out. Don't bother trying to
update native priority, it is diffcult to get right and likely
to end up horribly wrong.  Use an honestly wrong fixed value
that seems to work; PUSER for user threads, and the interrupt
priority for ithreads.  Set it once when the process is created
and forget about it.

Suggested by:	bde
Pointy hat:	me
2001-02-28 02:53:44 +00:00
John Baldwin
de271f01c2 Work around a race condition where an interrupt handler can be removed from
an interrupt thread while the interrupt thread is blocked on Giant waiting
to execute the interrupt handler being removed.  The result was that the
intrhand structure would be free'd, and we would call 0xdeadc0de.  The work
around is to check to see if the interrupt thread is idle when removing a
handler.  If not, then we mark the interrupt handler as being dead using
the new IH_DEAD flag and don't remove it from the interrupt threads' list
of handlers.  When the interrupt thread resumes, it will see a dead handler
while traversing the list of handlers and will remove the handler then.
2001-02-22 02:18:32 +00:00
John Baldwin
60f2b032fe Just use the ithread->it_proc directly in a KTR tracepoint instead of
assigning a local var to it and using it, as otherwise the local var wasn't
used, and generated a warning in the !KTR case.

Noticed by:	bde
2001-02-22 02:15:57 +00:00
John Baldwin
addec20c38 Add KTR tracepoints for adding/removing interrupt handlers,
creating/destroying interrupt threads, and updating the state of an
interrupt thread.
2001-02-22 02:14:08 +00:00
John Baldwin
76bd604e7d Fix a bug where the 'ithread' variable was being set in a KASSERT()
condition and thus was not initialized properly in the !INVARIANTS case.

Noticed by:	bde
Pointy hat to:	me
2001-02-22 00:23:56 +00:00
John Baldwin
719f43d3df Remove attempt to add in PREEMPTION #ifdef test in MI code that didn't
work because opt_preemption.h wasn't #include'd.  Instead, make use of the
do_switch parameter to ithread_schedule() and do the check in the alpha
interrupt code.
2001-02-21 22:51:00 +00:00