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286 Commits

Author SHA1 Message Date
Tor Egge
57051fdc4b Close race between vmspace_exitfree() and exit1() and races between
vmspace_exitfree() and vmspace_free() which could result in the same
vmspace being freed twice.

Factor out part of exit1() into new function vmspace_exit().  Attach
to vmspace0 to allow old vmspace to be freed earlier.

Add new function, vmspace_acquire_ref(), for obtaining a vmspace
reference for a vmspace belonging to another process.  Avoid changing
vmspace refcount from 0 to 1 since that could also lead to the same
vmspace being freed twice.

Change vmtotal() and swapout_procs() to use vmspace_acquire_ref().

Reviewed by:	alc
2006-05-29 21:28:56 +00:00
Christian S.J. Peron
d5e5634075 Kill the last Giant acquisition in the exit(2) code. This Giant acquisition
doesn't appear to be protecting anything. Most of consumers funsetownlst(9)
do not appear to be picking up Giant anywhere. This was originally a part
of my Giant exit(2) clean up revision 1.272 but I thought it was a good idea
to leave it out until we were able to analyze it better.

Tested by:	kris
MFC after:	3 weeks
2006-04-10 14:07:28 +00:00
Peter Wemm
b9eee07e36 Remove the unused sva and eva arguments from pmap_remove_pages(). 2006-04-03 21:16:10 +00:00
David Xu
e170bfda56 1. Count last time slice, this intends to fix
"calcru: runtime went backwards" bug for threaded process.
2. Add comment about possible logical problem with scheduler.

MFC after: 3 days
2006-03-14 04:00:21 +00:00
John Baldwin
06ad42b2f7 Close some races between procfs/ptrace and exit(2):
- Reorder the events in exit(2) slightly so that we trigger the S_EXIT
  stop event earlier.  After we have signalled that, we set P_WEXIT and
  then wait for any processes with a hold on the vmspace via PHOLD to
  release it.  PHOLD now KASSERT()'s that P_WEXIT is clear when it is
  invoked, and PRELE now does a wakeup if P_WEXIT is set and p_lock drops
  to zero.
- Change proc_rwmem() to require that the processing read from has its
  vmspace held via PHOLD by the caller and get rid of all the junk to
  screw around with the vmspace reference count as we no longer need it.
- In ptrace() and pseudofs(), treat a process with P_WEXIT set as if it
  doesn't exist.
- Only do one PHOLD in kern_ptrace() now, and do it earlier so it covers
  FIX_SSTEP() (since on alpha at least this can end up calling proc_rwmem()
  to clear an earlier single-step simualted via a breakpoint).  We only
  do one to avoid races.  Also, by making the EINVAL error for unknown
  requests be part of the default: case in the switch, the various
  switch cases can now just break out to return which removes a _lot_ of
  duplicated PRELE and proc unlocks, etc.  Also, it fixes at least one bug
  where a LWP ptrace command could return EINVAL with the proc lock still
  held.
- Changed the locking for ptrace_single_step(), ptrace_set_pc(), and
  ptrace_clear_single_step() to always be called with the proc lock
  held (it was a mixed bag previously).  Alpha and arm have to drop
  the lock while the mess around with breakpoints, but other archs
  avoid extra lock release/acquires in ptrace().  I did have to fix a
  couple of other consumers in kern_kse and a few other places to
  hold the proc lock and PHOLD.

Tested by:	ps (1 mostly, but some bits of 2-4 as well)
MFC after:	1 week
2006-02-22 18:57:50 +00:00
John Baldwin
bd106be404 Move the ruadd() in kern_exit() to save our final stats in our child
stats even further down in exit1() so that it includes the runtime and
tick counts from the final time slice for the dying thread.

Reviewed by:	phk
2006-02-21 21:48:42 +00:00
Poul-Henning Kamp
e8444a7e6f CPU time accounting speedup (step 2)
Keep accounting time (in per-cpu) cputicks and the statistics counts
in the thread and summarize into struct proc when at context switch.

Don't reach across CPUs in calcru().

Add code to calibrate the top speed of cpu_tickrate() for variable
cpu_tick hardware (like TSC on power managed machines).

Don't enforce monotonicity (at least for now) in calcru.  While the
calibrated cpu_tickrate ramps up it may not be true.

Use 27MHz counter on i386/Geode.

Use TSC on amd64 & i386 if present.

Use tick counter on sparc64
2006-02-11 09:33:07 +00:00
Poul-Henning Kamp
5b1a8eb397 Modify the way we account for CPU time spent (step 1)
Keep track of time spent by the cpu in various contexts in units of
"cputicks" and scale to real-world microsec^H^H^H^H^H^H^H^Hclock_t
only when somebody wants to inspect the numbers.

For now "cputicks" are still derived from the current timecounter
and therefore things should by definition remain sensible also on
SMP machines.  (The main reason for this first milestone commit is
to verify that hypothesis.)

On slower machines, the avoided multiplications to normalize timestams
at every context switch, comes out as a 5-7% better score on the
unixbench/context1 microbenchmark.  On more modern hardware no change
in performance is seen.
2006-02-07 21:22:02 +00:00
John Baldwin
934ba9b2cf - Move the wakeup() for exiting kthreads out of exit1() and into
kthread_exit() as that is cleaner and less obscured.  It also does the
  wakeup sooner.
- Add some comments to kthread_exit().
2006-02-06 21:56:13 +00:00
Wayne Salamon
de3007e8f3 Audit the pid being requested in wait4().
Obtained from: TrustedBSD Project
Approved by: rwatson (mentor)
2006-02-06 00:19:09 +00:00
Robert Watson
00c28d9678 On process exit, audit the return value of the process, and commit the
record immediately, as this system call never returns.

Obtained from:	TrustedBSD Project
2006-02-05 21:08:25 +00:00
John Baldwin
37f84a6018 Add a comment. 2006-02-03 21:09:40 +00:00
Robert Watson
fcf7f27a36 Hook up audit to fork() and exit() events. These changes manage the
audit state on processes, not auditing of these events.

Much work by:	wsalamon
Obtained from:	TrustedBSD Project
2006-02-02 01:32:58 +00:00
Stephan Uphoff
03001f59c8 Hopefully fix the "calcru: runtime went backwards from ..." problem by
keeping the resource values locked (where needed) while we use them
for calculations.

MFC after:	3 days
2006-01-23 19:15:13 +00:00
Poul-Henning Kamp
25f6e35a05 Regenerate sysent with new abort2 system call.
Implement abort2(const char *reason, int narg, void **args);

Submitted by:	"Wojciech A. Koszek" <dunstan@freebsd.czest.pl>
2005-12-23 11:58:42 +00:00
David Xu
d26b1a1fb9 Register itimers_event_hook as a kernel event handler, so I don't
have to duplicate code to call it in exec() and exit1().
2005-12-09 05:43:26 +00:00
Robert Watson
2c255e9df6 Moderate rewrite of kernel ktrace code to attempt to generally improve
reliability when tracing fast-moving processes or writing traces to
slow file systems by avoiding unbounded queueuing and dropped records.
Record loss was previously possible when the global pool of records
become depleted as a result of record generation outstripping record
commit, which occurred quickly in many common situations.

These changes partially restore the 4.x model of committing ktrace
records at the point of trace generation (synchronous), but maintain
the 5.x deferred record commit behavior (asynchronous) for situations
where entering VFS and sleeping is not possible (i.e., in the
scheduler).  Records are now queued per-process as opposed to
globally, with processes responsible for committing records from their
own context as required.

- Eliminate the ktrace worker thread and global record queue, as they
  are no longer used.  Keep the global free record list, as records
  are still used.

- Add a per-process record queue, which will hold any asynchronously
  generated records, such as from context switches.  This replaces the
  global queue as the place to submit asynchronous records to.

- When a record is committed asynchronously, simply queue it to the
  process.

- When a record is committed synchronously, first drain any pending
  per-process records in order to maintain ordering as best we can.
  Currently ordering between competing threads is provided via a global
  ktrace_sx, but a per-process flag or lock may be desirable in the
  future.

- When a process returns to user space following a system call, trap,
  signal delivery, etc, flush any pending records.

- When a process exits, flush any pending records.

- Assert on process tear-down that there are no pending records.

- Slightly abstract the notion of being "in ktrace", which is used to
  prevent the recursive generation of records, as well as generating
  traces for ktrace events.

Future work here might look at changing the set of events marked for
synchronous and asynchronous record generation, re-balancing queue
depth, timeliness of commit to disk, and so on.  I.e., performing a
drain every (n) records.

MFC after:	1 month
Discussed with:	jhb
Requested by:	Marc Olzheim <marcolz at stack dot nl>
2005-11-13 13:27:44 +00:00
Christian S.J. Peron
576068804d Giant clean up for exit(2)
-Change unconditional aquisition of Giant to only pickup Giant if the vnode
 for the controlling tty resides on a non-mpsafe file system.
-Pickup Giant around executable vnode reference counting operations only if
 the executable resides on a non-mpsafe file system.
-If this process is being traced, pickup Giant for trace file reference count
 operations only if it resides on a non-mpsafe file system.

Discussed with:	jhb
Tested by:	kris
2005-11-08 17:11:03 +00:00
David Xu
ebceaf6dc7 Add support for queueing SIGCHLD same as other UNIX systems did.
For each child process whose status has been changed, a SIGCHLD instance
is queued, if the signal is stilling pending, and process changed status
several times, signal information is updated to reflect latest process
status. If wait() returns because the status of a child process is
available, pending SIGCHLD signal associated with the child process is
discarded. Any other pending SIGCHLD signals remain pending.

The signal information is allocated at the same time when proc structure
is allocated, if process signal queue is fully filled or there is a memory
shortage, it can still send the signal to process.

There is a booting time tunable kern.sigqueue.queue_sigchild which
can control the behavior, setting it to zero disables the SIGCHLD queueing
feature, the tunable will be removed if the function is proved that it is
stable enough.

Tested on: i386 (SMP and UP)
2005-11-08 09:09:26 +00:00
John Baldwin
68a17869c1 Push down Giant into fdfree() and remove it from two of the callers.
Other callers such as some rfork() cases weren't locking Giant anyway.

Reviewed by:	csjp
MFC after:	1 week
2005-11-01 17:13:05 +00:00
Gleb Smirnoff
c0bc2867c1 - Fix leak of struct nlminfo on process exit.
- Fix malloc type collision, that made the above problem
  difficult to understand.

Reported by:	Vladimir Sharun <sharun ukr.net>
2005-10-26 07:18:37 +00:00
David Xu
60354683d9 Make p_itimers as a pointer, so file sys/proc.h does not need to include
sys/timers.h.
2005-10-23 12:19:08 +00:00
David Xu
86857b368d Implement POSIX timers. Current only CLOCK_REALTIME and CLOCK_MONOTONIC
clock are supported. I have plan to merge XSI timer ITIMER_REAL and other
two CPU timers into the new code, current three slots are available for
the XSI timers.
The SIGEV_THREAD notification type is not supported yet because our
sigevent struct lacks of two member fields:
sigev_notify_function
sigev_notify_attributes
I have found the sigevent is used in AIO, so I won't add the two members
unless the AIO code is adjusted.
2005-10-23 04:22:56 +00:00
David Xu
9104847f21 1. Change prototype of trapsignal and sendsig to use ksiginfo_t *, most
changes in MD code are trivial, before this change, trapsignal and
   sendsig use discrete parameters, now they uses member fields of
   ksiginfo_t structure. For sendsig, this change allows us to pass
   POSIX realtime signal value to user code.

2. Remove cpu_thread_siginfo, it is no longer needed because we now always
   generate ksiginfo_t data and feed it to libpthread.

3. Add p_sigqueue to proc structure to hold shared signals which were
   blocked by all threads in the proc.

4. Add td_sigqueue to thread structure to hold all signals delivered to
   thread.

5. i386 and amd64 now return POSIX standard si_code, other arches will
   be fixed.

6. In this sigqueue implementation, pending signal set is kept as before,
   an extra siginfo list holds additional siginfo_t data for signals.
   kernel code uses psignal() still behavior as before, it won't be failed
   even under memory pressure, only exception is when deleting a signal,
   we should call sigqueue_delete to remove signal from sigqueue but
   not SIGDELSET. Current there is no kernel code will deliver a signal
   with additional data, so kernel should be as stable as before,
   a ksiginfo can carry more information, for example, allow signal to
   be delivered but throw away siginfo data if memory is not enough.
   SIGKILL and SIGSTOP have fast path in sigqueue_add, because they can
   not be caught or masked.
   The sigqueue() syscall allows user code to queue a signal to target
   process, if resource is unavailable, EAGAIN will be returned as
   specification said.
   Just before thread exits, signal queue memory will be freed by
   sigqueue_flush.
   Current, all signals are allowed to be queued, not only realtime signals.

Earlier patch reviewed by: jhb, deischen
Tested on: i386, amd64
2005-10-14 12:43:47 +00:00
John Baldwin
83de502d59 Add witness warnings to panic if a thread tries to exit while holding any
locks.

Requested by:	jeff
MFC after:	3 days
2005-09-02 20:20:01 +00:00
John Baldwin
ddf9c4f771 - Slightly reorder the events around the setting of PRS_ZOMBIE to be less
hokie and much more readable and expand the comment to explain why it is
  the way that it is.
- Close a race where one CPU could free the process belonging to a thread
  on another CPU that hasn't quite finished exiting yet but is beyond the
  point of setting the process state as PRS_ZOMBIE.

Reported and tested by:	ps (2)
MFC after:	3 days
2005-07-18 20:08:14 +00:00
Stephan Uphoff
d13ec71369 Use low level constructs borrowed from interrupt threads to wait for
work in proc0.
Remove the TDP_WAKEPROC0 workaround.
2005-05-23 23:01:53 +00:00
David Xu
5a2f73e624 Only check signal event, single threading event shouldn't be reported. 2005-05-05 06:42:02 +00:00
David Xu
bc247e78c0 Wake up swapper process if needed.
PR: kern/78474
Submitted by: Sam Lawrance <boris at brooknet dot com dot au>
2005-04-23 05:06:44 +00:00
David Xu
902c0d8297 Clear P_STATCHILD earlier to avoid unnecessary retrying. 2005-04-19 12:31:15 +00:00
David Xu
95992d56f5 Fix a race condition between kern_wait() and thread_stopped().
Problem is in kern_wait(), parent process steps through children list,
once a child process is skipped, and later even if the child is stopped,
parent process still sleeps in msleep(), the race happens if parent
masked SIGCHLD.

Submitted by : Peter Edwards peadar.edwards at gmail dot com
MFC after    : 4 days
2005-04-19 08:07:28 +00:00
Robert Watson
babe9a2bb3 Introduce p_canwait() and MAC Framework and MAC Policy entry points
mac_check_proc_wait(), which control the ability to wait4() specific
processes.  This permits MAC policies to limit information flow from
children that have changed label, although has to be handled carefully
due to common programming expectations regarding the behavior of
wait4().  The cr_seeotheruids() check in p_canwait() is #if 0'd for
this reason.

The mac_stub and mac_test policies are updated to reflect these new
entry points.

Sponsored by:	SPAWAR, SPARTA
Obtained from:	TrustedBSD Project
2005-04-18 13:36:57 +00:00
Jeff Roberson
2b3183a8b7 - A lock is required before calling VOP_REVOKE. Our reference protects us
from accessing another vnode so a naked VOP_LOCK is sufficient.

Sponsored by:	Isilon Systems, Inc.
2005-03-13 11:47:04 +00:00
Poul-Henning Kamp
a258707313 In 1.276 of kern/subr_trap.c I introduced a mechanism for delaying
a process return to userspace if it had pending GEOM events.

We need to have the same check in the exit pass to catch the case
where a GEOM related filedescriptor is not explicitly closed by
the process.

Bumped into by:	people using dd(1) to build releases, nanobsd etc.
2005-01-29 14:03:41 +00:00
Robert Watson
fd544ee8f7 In kern_wait(), let the compiler copy the rusage structure rather than
an explicit bcopy() -- it probably does a better job.
2005-01-08 04:17:48 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
John Baldwin
c88379381b - Move the function prototypes for kern_setrlimit() and kern_wait() to
sys/syscallsubr.h where all the other kern_foo() prototypes live.
- Resort kern_execve() while I'm there.
2005-01-05 22:19:44 +00:00
David Schultz
6004362e66 Don't include sys/user.h merely for its side-effect of recursively
including other headers.
2004-11-27 06:51:39 +00:00
David Xu
c283653201 Remove P_STOPPED_TRACE bit if debugger dies without a chance to
detach debugged process.
2004-10-23 11:20:26 +00:00
John Baldwin
78c85e8dfc Rework how we store process times in the kernel such that we always store
the raw values including for child process statistics and only compute the
system and user timevals on demand.

- Fix the various kern_wait() syscall wrappers to only pass in a rusage
  pointer if they are going to use the result.
- Add a kern_getrusage() function for the ABI syscalls to use so that they
  don't have to play stackgap games to call getrusage().
- Fix the svr4_sys_times() syscall to just call calcru() to calculate the
  times it needs rather than calling getrusage() twice with associated
  stackgap, etc.
- Add a new rusage_ext structure to store raw time stats such as tick counts
  for user, system, and interrupt time as well as a bintime of the total
  runtime.  A new p_rux field in struct proc replaces the same inline fields
  from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime).  A new p_crux
  field in struct proc contains the "raw" child time usage statistics.
  ruadd() has been changed to handle adding the associated rusage_ext
  structures as well as the values in rusage.  Effectively, the values in
  rusage_ext replace the ru_utime and ru_stime values in struct rusage.  These
  two fields in struct rusage are no longer used in the kernel.
- calcru() has been split into a static worker function calcru1() that
  calculates appropriate timevals for user and system time as well as updating
  the rux_[isu]u fields of a passed in rusage_ext structure.  calcru() uses a
  copy of the process' p_rux structure to compute the timevals after updating
  the runtime appropriately if any of the threads in that process are
  currently executing.  It also now only locks sched_lock internally while
  doing the rux_runtime fixup.  calcru() now only requires the caller to
  hold the proc lock and calcru1() only requires the proc lock internally.
  calcru() also no longer allows callers to ask for an interrupt timeval
  since none of them actually did.
- calcru() now correctly handles threads executing on other CPUs.
- A new calccru() function computes the child system and user timevals by
  calling calcru1() on p_crux.  Note that this means that any code that wants
  child times must now call this function rather than reading from p_cru
  directly.  This function also requires the proc lock.
- This finishes the locking for rusage and friends so some of the Giant locks
  in exit1() and kern_wait() are now gone.
- The locking in ttyinfo() has been tweaked so that a shared lock of the
  proctree lock is used to protect the process group rather than the process
  group lock.  By holding this lock until the end of the function we now
  ensure that the process/thread that we pick to dump info about will no
  longer vanish while we are trying to output its info to the console.

Submitted by:	bde (mostly)
MFC after:	1 month
2004-10-05 18:51:11 +00:00
John Baldwin
a9a64385e7 Some more whitespace, style, and comment fixes.
Submitted by:	bde (mostly)
2004-09-24 20:27:04 +00:00
John Baldwin
6111dcd2ef A modest collection of various and sundry style, spelling, and whitespace
fixes.

Submitted by:	bde (mostly)
2004-09-24 00:38:15 +00:00
John Baldwin
7eaec467d8 Various small style fixes. 2004-09-22 15:24:33 +00:00
Julian Elischer
ed062c8d66 Refactor a bunch of scheduler code to give basically the same behaviour
but with slightly cleaned up interfaces.

The KSE structure has become the same as the "per thread scheduler
private data" structure. In order to not make the diffs too great
one is #defined as the other at this time.

The KSE (or td_sched) structure is  now allocated per thread and has no
allocation code of its own.

Concurrency for a KSEGRP is now kept track of via a simple pair of counters
rather than using KSE structures as tokens.

Since the KSE structure is different in each scheduler, kern_switch.c
is now included at the end of each scheduler. Nothing outside the
scheduler knows the contents of the KSE (aka td_sched) structure.

The fields in the ksegrp structure that are to do with the scheduler's
queueing mechanisms are now moved to the kg_sched structure.
(per ksegrp scheduler private data structure). In other words how the
scheduler queues and keeps track of threads is no-one's business except
the scheduler's. This should allow people to write experimental
schedulers with completely different internal structuring.

A scheduler call sched_set_concurrency(kg, N) has been added that
notifies teh scheduler that no more than N threads from that ksegrp
should be allowed to be on concurrently scheduled. This is also
used to enforce 'fainess' at this time so that a ksegrp with
10000 threads can not swamp a the run queue and force out a process
with 1 thread, since the current code will not set the concurrency above
NCPU, and both schedulers will not allow more than that many
onto the system run queue at a time. Each scheduler should eventualy develop
their own methods to do this now that they are effectively separated.

Rejig libthr's kernel interface to follow the same code paths as
linkse for scope system threads. This has slightly hurt libthr's performance
but I will work to recover as much of it as I can.

Thread exit code has been cleaned up greatly.
exit and exec code now transitions a process back to
'standard non-threaded mode' before taking the next step.
Reviewed by:	scottl, peter
MFC after:	1 week
2004-09-05 02:09:54 +00:00
John-Mark Gurney
ad3b9257c2 Add locking to the kqueue subsystem. This also makes the kqueue subsystem
a more complete subsystem, and removes the knowlege of how things are
implemented from the drivers.  Include locking around filter ops, so a
module like aio will know when not to be unloaded if there are outstanding
knotes using it's filter ops.

Currently, it uses the MTX_DUPOK even though it is not always safe to
aquire duplicate locks.  Witness currently doesn't support the ability
to discover if a dup lock is ok (in some cases).

Reviewed by:	green, rwatson (both earlier versions)
2004-08-15 06:24:42 +00:00
Alan Cox
9be60284a6 Giant is no longer required by vm_waitproc() and vmspace_exitfree().
Eliminate it acquisition and release around vm_waitproc() in kern_wait().
2004-07-30 20:31:02 +00:00
Alan Cox
1a276a3f91 - Use atomic ops for updating the vmspace's refcnt and exitingcnt.
- Push down Giant into shmexit().  (Giant is acquired only if the vmspace
   contains shm segments.)
 - Eliminate the acquisition of Giant from proc_rwmem().
 - Reduce the scope of Giant in exit1(), uncovering the destruction of the
   address space.
2004-07-27 03:53:41 +00:00
Julian Elischer
55d44f79ea When calling scheduler entrypoints for creating new threads and processes,
specify "us" as the thread not the process/ksegrp/kse.
You can always find the others from the thread but the converse is not true.
Theorotically this would lead to runtime being allocated to the wrong
entity in some cases though it is not clear how often this actually happenned.
(would only affect threaded processes and would probably be pretty benign,
but it WAS a bug..)

Reviewed by: peter
2004-07-18 23:36:13 +00:00
David Xu
cbf4e354ec Add code to support debugging threaded process.
1. Add tm_lwpid into kse_thr_mailbox to indicate which kernel
   thread current user thread is running on. Add tm_dflags into
   kse_thr_mailbox, the flags is written by debugger, it tells
   UTS and kernel what should be done when the process is being
   debugged, current, there two flags TMDF_SSTEP and TMDF_DONOTRUNUSER.

   TMDF_SSTEP is used to tell kernel to turn on single stepping,
   or turn off if it is not set.

   TMDF_DONOTRUNUSER is used to tell kernel to schedule upcall
   whenever possible, to UTS, it means do not run the user thread
   until debugger clears it, this behaviour is necessary because
   gdb wants to resume only one thread when the thread's pc is
   at a breakpoint, and thread needs to go forward, in order to
   avoid other threads sneak pass the breakpoints, it needs to remove
   breakpoint, only wants one thread to go. Also, add km_lwp to
   kse_mailbox, the lwp id is copied to kse_thr_mailbox at context
   switch time when process is not being debugged, so when process
   is attached, debugger can map kernel thread to user thread.

2. Add p_xthread to proc strcuture and td_xsig to thread structure.
   p_xthread is used by a thread when it wants to report event
   to debugger, every thread can set the pointer, especially, when
   it is used in ptracestop, it is the last thread reporting event
   will win the race. Every thread has a td_xsig to exchange signal
   with debugger, thread uses TDF_XSIG flag to indicate it is reporting
   signal to debugger, if the flag is not cleared, thread will keep
   retrying until it is cleared by debugger, p_xthread may be
   used by debugger to indicate CURRENT thread. The p_xstat is still
   in proc structure to keep wait() to work, in future, we may
   just use td_xsig.

3. Add TDF_DBSUSPEND flag, the flag is used by debugger to suspend
   a thread. When process stops, debugger can set the flag for
   thread, thread will check the flag in thread_suspend_check,
   enters a loop, unless it is cleared by debugger, process is
   detached or process is existing. The flag is also checked in
   ptracestop, so debugger can temporarily suspend a thread even
   if the thread wants to exchange signal.

4. Current, in ptrace, we always resume all threads, but if a thread
   has already a TDF_DBSUSPEND flag set by debugger, it won't run.

Encouraged by: marcel, julian, deischen
2004-07-13 07:20:10 +00:00
Alan Cox
ce8da3091f Push down the acquisition and release of the page queues lock into
pmap_remove_pages().  (The implementation of pmap_remove_pages() is
optional.  If pmap_remove_pages() is unimplemented, the acquisition and
release of the page queues lock is unnecessary.)

Remove spl calls from the alpha, arm, and ia64 pmap_remove_pages().
2004-07-13 02:49:22 +00:00