Commit Graph

101 Commits

Author SHA1 Message Date
Konstantin Belousov
9768156746 Stop treating td_sigmask specially for the purposes of new thread
creation. Move it into the copied region of the struct thread.

Update some comments.

Requested by:	bde
X-MFC after:	never
2012-05-26 20:03:47 +00:00
Edward Tomasz Napierala
47f6635cc1 Fix panic, triggered like this: "int main() { thr_exit(); }"
Submitted by:	Mateusz Guzik
2012-04-17 13:44:40 +00:00
John Baldwin
44ad547522 Add a new sched_clear_name() method to the scheduler interface to clear
the cached name used for KTR_SCHED traces when a thread's name changes.
This way KTR_SCHED traces (and thus schedgraph) will notice when a thread's
name changes, most commonly via execve().

MFC after:	2 weeks
2012-03-08 19:41:05 +00:00
Eitan Adler
3eb9ab5255 Document a large number of currently undocumented sysctls. While here
fix some style(9) issues and reduce redundancy.

PR:		kern/155491
PR:		kern/155490
PR:		kern/155489
Submitted by:	Galimov Albert <wtfcrap@mail.ru>
Approved by:	bde
Reviewed by:	jhb
MFC after:	1 week
2011-12-13 00:38:50 +00:00
Peter Holm
cdea31e305 Move cpu_set_upcall(newtd, td) up before the first call of
thread_free(newtd).  This to avoid a possible page fault in
cpu_thread_clean() as seen on amd64 with syscall fuzzing.

Reviewed by:	kib
MFC after:	1 week
2011-12-09 17:19:41 +00:00
Peter Holm
9a1d0cf68f Use umtx_copyin_timeout() to copy and check timeout parameter.
In collaboration with:	kib
MFC after:	1 week
2011-12-03 12:35:13 +00:00
Peter Holm
7bbcd22d38 Added check for negative seconds value. Found by syscall() fuzzing.
MFC after:	1 week
2011-11-18 19:14:42 +00:00
Ed Schouten
6472ac3d8a Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
2011-11-07 15:43:11 +00:00
Kip Macy
8451d0dd78 In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00
Edward Tomasz Napierala
afcc55f318 All the racct_*() calls need to happen with the proc locked. Fixing this
won't happen before 9.0.  This commit adds "#ifdef RACCT" around all the
"PROC_LOCK(p); racct_whatever(p, ...); PROC_UNLOCK(p)" instances, in order
to avoid useless locking/unlocking in kernels built without "options RACCT".
2011-07-06 20:06:44 +00:00
Edward Tomasz Napierala
58c77a9d53 Enable accounting for RACCT_NPROC and RACCT_NTHR.
Sponsored by:	The FreeBSD Foundation
Reviewed by:	kib (earlier version)
2011-03-31 19:22:11 +00:00
Konstantin Belousov
25a9cfc9e8 Move the max_threads_per_proc and max_threads_hits variables to the
file where they are used. Declare the kern.threads sysctl node at the
same location. Since no external use for the variables exists, make them
static.

Discussed with:	dchagin
MFC after:	1 week
2011-02-23 13:50:24 +00:00
John Baldwin
a328d5359c Revert previous change, the existing check was correct.
Pointy hat to:	jhb
2011-02-23 13:25:42 +00:00
John Baldwin
329b4acb91 Fix off-by-one error in check against max_threads_per_proc.
Submitted by:	arundel
MFC after:	1 week
2011-02-23 12:56:25 +00:00
David Xu
0d036d55e7 In thr_exit() and kthread_exit(), only remove thread from
hash if it can directly exit, otherwise let exit1() do it.
The change should be in r213950, but for unknown reason,
it was lost.
2010-10-23 13:16:39 +00:00
David Xu
cfca8a1862 - Don't include sx.h, it is not needed.
- Check NULL pointer, move timeout calculation code outside of
  process lock.
2010-10-20 00:41:38 +00:00
David Xu
cf7d9a8ca8 Create a global thread hash table to speed up thread lookup, use
rwlock to protect the table. In old code, thread lookup is done with
process lock held, to find a thread, kernel has to iterate through
process and thread list, this is quite inefficient.
With this change, test shows in extreme case performance is
dramatically improved.

Earlier patch was reviewed by: jhb, julian
2010-10-09 02:50:23 +00:00
David Xu
2961a78226 Optimize thr_suspend, if timeout is zero, don't call msleep, just
return immediately.
2010-08-24 07:29:55 +00:00
David Xu
baf28b69f4 - According to specification, SI_USER code should only be generated by
standard kill(). On other systems, SI_LWP is generated by lwp_kill().
  This will allow conforming applications to differentiate between
  signals generated by standard events and those generated by other
  implementation events in a manner compatible with existing practice.
- Bump __FreeBSD_version
2010-08-24 07:22:24 +00:00
John Baldwin
ad6eec7b9e Tweak the in-kernel API for sending signals to threads:
- Rename tdsignal() to tdsendsignal() and make it private to kern_sig.c.
- Add tdsignal() and tdksignal() routines that mirror psignal() and
  pksignal() except that they accept a thread as an argument instead of
  a process.  They send a signal to a specific thread rather than to an
  individual process.

Reviewed by:	kib
2010-06-29 20:41:52 +00:00
Nathan Whitehorn
841c0c7ec7 Provide groundwork for 32-bit binary compatibility on non-x86 platforms,
for upcoming 64-bit PowerPC and MIPS support. This renames the COMPAT_IA32
option to COMPAT_FREEBSD32, removes some IA32-specific code from MI parts
of the kernel and enhances the freebsd32 compatibility code to support
big-endian platforms.

Reviewed by:	kib, jhb
2010-03-11 14:49:06 +00:00
Bruno Ducrot
5f73a7eb08 Deliver siginfo when signal is generated by thr_kill(2) (SI_USER with properly
filled si_uid and si_pid).

Reported by:	Joel Bertrand <joel.bertrand systella fr>
PR:		141956
Reviewed by:	kib
MFC after:	2 weeks
2010-03-01 14:27:16 +00:00
Konstantin Belousov
6b286ee8b5 Currently, when signal is delivered to the process and there is a thread
not blocking the signal, signal is placed on the thread sigqueue. If
the selected thread is in kernel executing thr_exit() or sigprocmask()
syscalls, then signal might be not delivered to usermode for arbitrary
amount of time, and for exiting thread it is lost.

Put process-directed signals to the process queue unconditionally,
selecting the thread to deliver the signal only by the thread returning
to usermode, since only then the thread can handle delivery of signal
reliably. For exiting thread or thread that has blocked some signals,
check whether the newly blocked signal is queued for the process, and
try to find a thread to wakeup for delivery, in reschedule_signal(). For
exiting thread, assume that all signals are blocked.

Change cursig() and postsig() to look both into the thread and process
signal queues. When there is a signal that thread returning to usermode
could consume, TDF_NEEDSIGCHK flag is not neccessary set now. Do
unlocked read of p_siglist and p_pendingcnt to check for queued signals.

Note that thread that has a signal unblocked might get spurious wakeup
and EINTR from the interruptible system call now, due to the possibility
of being selected by reschedule_signals(), while other thread returned
to usermode earlier and removed the signal from process queue. This
should not cause compliance issues, since the thread has not blocked a
signal and thus should be ready to receive it anyway.

Reported by:	Justin Teller <justin.teller gmail com>
Reviewed by:	davidxu, jilles
MFC after:	1 month
2009-10-11 16:49:30 +00:00
Konstantin Belousov
8a945d109c Reintroduce the r196640, after fixing the problem with my testing.
Remove the altkstacks, instead instantiate threads with kernel stack
allocated with the right size from the start. For the thread that has
kernel stack cached, verify that requested stack size is equial to the
actual, and reallocate the stack if sizes differ [1].

This fixes the bug introduced by r173361 that was committed several days
after r173004 and consisted of kthread_add(9) ignoring the non-default
kernel stack size.

Also, r173361 removed the caching of the kernel stacks for a non-first
thread in the process. Introduce separate kernel stack cache that keeps
some limited amount of preallocated kernel stacks to lower the latency
of thread allocation. Add vm_lowmem handler to prune the cache on
low memory condition. This way, system with reasonable amount of the
threads get lower latency of thread creation, while still not exhausting
significant portion of KVA for unused kstacks.

Submitted by:	peter [1]
Discussed with:	jhb, julian, peter
Reviewed by:	jhb
Tested by:	pho (and retested according to new test scenarious)
MFC after:	1 week
2009-09-01 11:41:51 +00:00
Konstantin Belousov
f25fa6abb2 Reverse r196640 and r196644 for now. 2009-08-29 21:53:08 +00:00
Konstantin Belousov
c3cf0b476f Remove the altkstacks, instead instantiate threads with kernel stack
allocated with the right size from the start. For the thread that has
kernel stack cached, verify that requested stack size is equial to the
actual, and reallocate the stack if sizes differ [1].

This fixes the bug introduced by r173361 that was committed several days
after r173004 and consisted of kthread_add(9) ignoring the non-default
kernel stack size.

Also, r173361 removed the caching of the kernel stacks for a non-first
thread in the process. Introduce separate kernel stack cache that keeps
some limited amount of preallocated kernel stacks to lower the latency
of thread allocation. Add vm_lowmem handler to prune the cache on
low memory condition. This way, system with reasonable amount of the
threads get lower latency of thread creation, while still not exhausting
significant portion of KVA for unused kstacks.

Submitted by:	peter [1]
Discussed with:	jhb, julian, peter
Reviewed by:	jhb
Tested by:	pho
MFC after:	1 week
2009-08-29 13:28:02 +00:00
Robert Watson
14961ba789 Replace AUDIT_ARG() with variable argument macros with a set more more
specific macros for each audit argument type.  This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).

In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.

Suggested by:	brooks
Approved by:	re (kib)
Obtained from:	TrustedBSD Project
MFC after:	1 week
2009-06-27 13:58:44 +00:00
Ed Schouten
c90c9021e9 Remove even more unneeded variable assignments.
kern_time.c:
- Unused variable `p'.

kern_thr.c:
- Variable `error' is always caught immediately, so no reason to
  initialize it. There is no way that error != 0 at the end of
  create_thread().

kern_sig.c:
- Unused variable `code'.

kern_synch.c:
- `rval' is always assigned in all different cases.

kern_rwlock.c:
- `v' is always overwritten with RW_UNLOCKED further on.

kern_malloc.c:
- `size' is always initialized with the proper value before being used.

kern_exit.c:
- `error' is always caught and returned immediately. abort2() never
  returns a non-zero value.

kern_exec.c:
- `len' is always assigned inside the if-statement right below it.

tty_info.c:
- `td' is always overwritten by FOREACH_THREAD_IN_PROC().

Found by:	LLVM's scan-build
2009-02-26 15:51:54 +00:00
Konstantin Belousov
b4cf0e62f4 Add sv_flags field to struct sysentvec with intention to provide description
of the ABI of the currently executing image. Change some places to test
the flags instead of explicit comparing with address of known sysentvec
structures to determine ABI features.

Discussed with:	dchagin, imp, jhb, peter
2008-11-22 12:36:15 +00:00
David Xu
7b4a950a7d Revert rev 184216 and 184199, due to the way the thread_lock works,
it may cause a lockup.

Noticed by: peter, jhb
2008-11-05 03:01:23 +00:00
David Xu
94ec9c0245 If threads limit is exceeded, increase the totoal number
of failures.
2008-10-29 12:11:48 +00:00
David Xu
3f9be10eb0 Actually, for signal and thread suspension, extra process spin lock is
unnecessary, the normal process lock and thread lock are enough. The
spin lock is still needed for process and thread exiting to mimic
single sched_lock.
2008-10-23 07:55:38 +00:00
Roman Divacky
e4866772c3 Check the result of copyin and in a case of error
return one. This prevents setting wrong priority
or (more likely) returning EINVAL.

Approved by:	kib (mentor)
2008-10-13 21:04:52 +00:00
David Xu
3bba58f287 Fix compiling problem. 2008-04-29 05:48:05 +00:00
David Xu
34d05d83f6 Remove commented out code, thread suspension is done in thread library. 2008-03-23 02:03:06 +00:00
Jeff Roberson
b7edba7704 - Add a new td flag TDF_NEEDSUSPCHK that is set whenever a thread needs
to enter thread_suspend_check().
 - Set TDF_ASTPENDING along with TDF_NEEDSUSPCHK so we can move the
   thread_suspend_check() to ast() rather than userret().
 - Check TDF_NEEDSUSPCHK in the sleepq_catch_signals() optimization so
   that we don't miss a suspend request.  If this is set use the
   expensive signal path.
 - Set NEEDSUSPCHK when creating a new thread in thr in case the
   creating thread is due to be suspended as well but has not yet.

Reviewed by:	davidxu (Authored original patch)
2008-03-21 08:23:25 +00:00
Jeff Roberson
374ae2a393 - Relax requirements for p_numthreads, p_threads, p_swtick, and p_nice from
requiring the per-process spinlock to only requiring the process lock.
 - Reflect these changes in the proc.h documentation and consumers throughout
   the kernel.  This is a substantial reduction in locking cost for these
   fields and was made possible by recent changes to threading support.
2008-03-19 06:19:01 +00:00
Julian Elischer
c67ddc21e7 This time REALLY copy the name from the proc to the thread as a default. 2007-11-15 06:35:26 +00:00
Konstantin Belousov
89b57fcf01 Fix for the panic("vm_thread_new: kstack allocation failed") and
silent NULL pointer dereference in the i386 and sparc64 pmap_pinit()
when the kmem_alloc_nofault() failed to allocate address space. Both
functions now return error instead of panicing or dereferencing NULL.

As consequence, vmspace_exec() and vmspace_unshare() returns the errno
int. struct vmspace arg was added to vm_forkproc() to avoid dealing
with failed allocation when most of the fork1() job is already done.

The kernel stack for the thread is now set up in the thread_alloc(),
that itself may return NULL. Also, allocation of the first process
thread is performed in the fork1() to properly deal with stack
allocation failure. proc_linkup() is separated into proc_linkup()
called from fork1(), and proc_linkup0(), that is used to set up the
kernel process (was known as swapper).

In collaboration with:	Peter Holm
Reviewed by:	jhb
2007-11-05 11:36:16 +00:00
David Xu
0b1f0611b4 Add thr_kill2 syscall which sends a signal to a thread in another process.
Submitted by: Tijl Coosemans tijl at ulyssis dot org
Approved by: re (kensmith)
2007-08-16 05:26:42 +00:00
John Baldwin
a66fde8d35 - Remove unused variable from create_thread().
- Move kern_thr_*() prototype to <sys/syscallsubr.h> where all the other
  kern_*() prototypes live.
2007-06-07 19:45:19 +00:00
Jeff Roberson
982d11f836 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
Jeff Roberson
f0393f063a - Remove setrunqueue and replace it with direct calls to sched_add().
setrunqueue() was mostly empty.  The few asserts and thread state
   setting were moved to the individual schedulers.  sched_add() was
   chosen to displace it for naming consistency reasons.
 - Remove adjustrunqueue, it was 4 lines of code that was ifdef'd to be
   different on all three schedulers where it was only called in one place
   each.
 - Remove the long ifdef'd out remrunqueue code.
 - Remove the now redundant ts_state.  Inspect the thread state directly.
 - Don't set TSF_* flags from kern_switch.c, we were only doing this to
   support a feature in one scheduler.
 - Change sched_choose() to return a thread rather than a td_sched.  Also,
   rely on the schedulers to return the idlethread.  This simplifies the
   logic in choosethread().  Aside from the run queue links kern_switch.c
   mostly does not care about the contents of td_sched.

Discussed with:	julian

 - Move the idle thread loop into the per scheduler area.  ULE wants to
   do something different from the other schedulers.

Suggested by:	jhb

Tested on:	x86/amd64 sched_{4BSD, ULE, CORE}.
2007-01-23 08:46:51 +00:00
Julian Elischer
ad1e7d285a Threading cleanup.. part 2 of several.
Make part of John Birrell's KSE patch permanent..
Specifically, remove:
Any reference of the ksegrp structure. This feature was
never fully utilised and made things overly complicated.
All code in the scheduler that tried to make threaded programs
fair to unthreaded programs.  Libpthread processes will already
do this to some extent and libthr processes already disable it.

Also:
Since this makes such a big change to the scheduler(s), take the opportunity
to rename some structures and elements that had to be moved anyhow.
This makes the code a lot more readable.

The ULE scheduler compiles again but I have no idea if it works.

The 4bsd scheduler still reqires a little cleaning and some functions that now do
ALMOST nothing will go away, but I thought I'd do that as a separate commit.

Tested by David Xu, and Dan Eischen using libthr and libpthread.
2006-12-06 06:34:57 +00:00
David Xu
745fbd3a72 if a thread blocked on userland condition variable is
pthread_cancel()ed, it is expected that the thread will not
consume a pthread_cond_signal(), therefor, we use thr_wake()
to mark a flag, the flag tells a thread calling do_cv_wait()
in umtx code to not block on a condition variable.
Thread library is expected that once a thread detected itself
is in pthread_cond_wait, it will call the thr_wake() for itself
in its SIGCANCEL handler.
2006-12-04 14:15:12 +00:00
Tom Rhodes
c4f7f0fd4a Update includes for sys/posix4 move.
Approved by:	silence on -arch and -standards
2006-11-11 16:46:31 +00:00
Robert Watson
acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
John Birrell
8460a577a4 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
David Xu
cda9a0d1c2 Add compatible code to let 32bit libthr work on 64bit kernel. 2006-09-22 15:04:28 +00:00
David Xu
73fa3e5b88 Replace system call thr_getscheduler, thr_setscheduler, thr_setschedparam
with rtprio_thread, while rtprio system call is for process only, the new
system call rtprio_thread is responsible for LWP.
2006-09-21 04:18:46 +00:00