Commit Graph

353 Commits

Author SHA1 Message Date
Mark Johnston
7159310fa6 The fasttrap fork handler is responsible for removing tracepoints in the
child process that were inherited from its parent. However, this should
not be done in the case of a vfork, since the fork handler ends up removing
the tracepoints from the shared vm space, and userland DTrace probes in the
parent will no longer fire as a result.

Now the child of a vfork may trigger userland DTrace probes enabled in its
parent, so modify the fasttrap probe handler to handle this case and handle
the child process in the same way that it would handle the traced process.
In particular, if once traces function foo() in a process that vforks, and
the child calls foo(), fasttrap will treat this call as having come from the
parent. This is the behaviour of the upstream code.

While here, add #ifdef guards to some code that isn't present upstream.

MFC after:	1 month
2013-12-18 01:41:52 +00:00
Pawel Jakub Dawidek
f2b525e6b9 Make process descriptors standard part of the kernel. rwhod(8) already
requires process descriptors to work and having PROCDESC in GENERIC
seems not enough, especially that we hope to have more and more consumers
in the base.

MFC after:	3 days
2013-11-30 15:08:35 +00:00
Andriy Gapon
d9fae5ab88 dtrace sdt: remove the ugly sname parameter of SDT_PROBE_DEFINE
In its stead use the Solaris / illumos approach of emulating '-' (dash)
in probe names with '__' (two consecutive underscores).

Reviewed by:	markj
MFC after:	3 weeks
2013-11-26 08:46:27 +00:00
Attilio Rao
54366c0bd7 - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging
option, unbreak the lock tracing release semantic by embedding
  calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
  version of the releasing functions for mutex, rwlock and sxlock.
  Failing to do so skips the lockstat_probe_func invokation for
  unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
  kernel compiled without lock debugging options, potentially every
  consumer must be compiled including opt_kdtrace.h.
  Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
  dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
  is linked there and it is only used as a compile-time stub [0].

[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested.  As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while.  Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].

Sponsored by:	EMC / Isilon storage division
Discussed with:	rstone
[0] Reported by:	rstone
[1] Discussed with:	philip
2013-11-25 07:38:45 +00:00
John Baldwin
55648840de Extend the support for exempting processes from being killed when swap is
exhausted.
- Add a new protect(1) command that can be used to set or revoke protection
  from arbitrary processes.  Similar to ktrace it can apply a change to all
  existing descendants of a process as well as future descendants.
- Add a new procctl(2) system call that provides a generic interface for
  control operations on processes (as opposed to the debugger-specific
  operations provided by ptrace(2)).  procctl(2) uses a combination of
  idtype_t and an id to identify the set of processes on which to operate
  similar to wait6().
- Add a PROC_SPROTECT control operation to manage the protection status
  of a set of processes.  MADV_PROTECT still works for backwards
  compatability.
- Add a p_flag2 to struct proc (and a corresponding ki_flag2 to kinfo_proc)
  the first bit of which is used to track if P_PROTECT should be inherited
  by new child processes.

Reviewed by:	kib, jilles (earlier version)
Approved by:	re (delphij)
MFC after:	1 month
2013-09-19 18:53:42 +00:00
Mark Johnston
7b77e1fe0f Specify SDT probe argument types in the probe definition itself rather than
using SDT_PROBE_ARGTYPE(). This will make it easy to extend the SDT(9) API
to allow probes with dynamically-translated types.

There is no functional change.

MFC after:	2 weeks
2013-08-15 04:08:55 +00:00
Jaakko Heinonen
a208417c41 Include PID in the error message which is printed when the maxproc limit
is exceeded. Improve formatting of the message while here.

PR:		kern/60550
Submitted by:	Lowell Gilbert, bde
2013-04-19 15:19:29 +00:00
Pawel Jakub Dawidek
2609222ab4 Merge Capsicum overhaul:
- Capability is no longer separate descriptor type. Now every descriptor
  has set of its own capability rights.

- The cap_new(2) system call is left, but it is no longer documented and
  should not be used in new code.

- The new syscall cap_rights_limit(2) should be used instead of
  cap_new(2), which limits capability rights of the given descriptor
  without creating a new one.

- The cap_getrights(2) syscall is renamed to cap_rights_get(2).

- If CAP_IOCTL capability right is present we can further reduce allowed
  ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed
  ioctls can be retrived with cap_ioctls_get(2) syscall.

- If CAP_FCNTL capability right is present we can further reduce fcntls
  that can be used with the new cap_fcntls_limit(2) syscall and retrive
  them with cap_fcntls_get(2).

- To support ioctl and fcntl white-listing the filedesc structure was
  heavly modified.

- The audit subsystem, kdump and procstat tools were updated to
  recognize new syscalls.

- Capability rights were revised and eventhough I tried hard to provide
  backward API and ABI compatibility there are some incompatible changes
  that are described in detail below:

	CAP_CREATE old behaviour:
	- Allow for openat(2)+O_CREAT.
	- Allow for linkat(2).
	- Allow for symlinkat(2).
	CAP_CREATE new behaviour:
	- Allow for openat(2)+O_CREAT.

	Added CAP_LINKAT:
	- Allow for linkat(2). ABI: Reuses CAP_RMDIR bit.
	- Allow to be target for renameat(2).

	Added CAP_SYMLINKAT:
	- Allow for symlinkat(2).

	Removed CAP_DELETE. Old behaviour:
	- Allow for unlinkat(2) when removing non-directory object.
	- Allow to be source for renameat(2).

	Removed CAP_RMDIR. Old behaviour:
	- Allow for unlinkat(2) when removing directory.

	Added CAP_RENAMEAT:
	- Required for source directory for the renameat(2) syscall.

	Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR):
	- Allow for unlinkat(2) on any object.
	- Required if target of renameat(2) exists and will be removed by this
	  call.

	Removed CAP_MAPEXEC.

	CAP_MMAP old behaviour:
	- Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and
	  PROT_WRITE.
	CAP_MMAP new behaviour:
	- Allow for mmap(2)+PROT_NONE.

	Added CAP_MMAP_R:
	- Allow for mmap(PROT_READ).
	Added CAP_MMAP_W:
	- Allow for mmap(PROT_WRITE).
	Added CAP_MMAP_X:
	- Allow for mmap(PROT_EXEC).
	Added CAP_MMAP_RW:
	- Allow for mmap(PROT_READ | PROT_WRITE).
	Added CAP_MMAP_RX:
	- Allow for mmap(PROT_READ | PROT_EXEC).
	Added CAP_MMAP_WX:
	- Allow for mmap(PROT_WRITE | PROT_EXEC).
	Added CAP_MMAP_RWX:
	- Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC).

	Renamed CAP_MKDIR to CAP_MKDIRAT.
	Renamed CAP_MKFIFO to CAP_MKFIFOAT.
	Renamed CAP_MKNODE to CAP_MKNODEAT.

	CAP_READ old behaviour:
	- Allow pread(2).
	- Disallow read(2), readv(2) (if there is no CAP_SEEK).
	CAP_READ new behaviour:
	- Allow read(2), readv(2).
	- Disallow pread(2) (CAP_SEEK was also required).

	CAP_WRITE old behaviour:
	- Allow pwrite(2).
	- Disallow write(2), writev(2) (if there is no CAP_SEEK).
	CAP_WRITE new behaviour:
	- Allow write(2), writev(2).
	- Disallow pwrite(2) (CAP_SEEK was also required).

	Added convinient defines:

	#define	CAP_PREAD		(CAP_SEEK | CAP_READ)
	#define	CAP_PWRITE		(CAP_SEEK | CAP_WRITE)
	#define	CAP_MMAP_R		(CAP_MMAP | CAP_SEEK | CAP_READ)
	#define	CAP_MMAP_W		(CAP_MMAP | CAP_SEEK | CAP_WRITE)
	#define	CAP_MMAP_X		(CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL)
	#define	CAP_MMAP_RW		(CAP_MMAP_R | CAP_MMAP_W)
	#define	CAP_MMAP_RX		(CAP_MMAP_R | CAP_MMAP_X)
	#define	CAP_MMAP_WX		(CAP_MMAP_W | CAP_MMAP_X)
	#define	CAP_MMAP_RWX		(CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X)
	#define	CAP_RECV		CAP_READ
	#define	CAP_SEND		CAP_WRITE

	#define	CAP_SOCK_CLIENT \
		(CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \
		 CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN)
	#define	CAP_SOCK_SERVER \
		(CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \
		 CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \
		 CAP_SETSOCKOPT | CAP_SHUTDOWN)

	Added defines for backward API compatibility:

	#define	CAP_MAPEXEC		CAP_MMAP_X
	#define	CAP_DELETE		CAP_UNLINKAT
	#define	CAP_MKDIR		CAP_MKDIRAT
	#define	CAP_RMDIR		CAP_UNLINKAT
	#define	CAP_MKFIFO		CAP_MKFIFOAT
	#define	CAP_MKNOD		CAP_MKNODAT
	#define	CAP_SOCK_ALL		(CAP_SOCK_CLIENT | CAP_SOCK_SERVER)

Sponsored by:	The FreeBSD Foundation
Reviewed by:	Christoph Mallon <christoph.mallon@gmx.de>
Many aspects discussed with:	rwatson, benl, jonathan
ABI compatibility discussed with:	kib
2013-03-02 00:53:12 +00:00
Pawel Jakub Dawidek
de26549841 Remove redundant parenthesis. 2013-02-17 11:47:01 +00:00
Konstantin Belousov
d4015944e7 Remove a special case for XEN, which is erronous and makes vfork(2)
behaviour to differ from the documented, only on XEN.  If there are
any issues with XEN pmap left, they should be fixed in pmap.

MFC after:	2 weeks
2012-12-15 02:02:11 +00:00
Konstantin Belousov
f7e50ea722 Fix a race between kern_setitimer() and realitexpire(), where the
callout is started before kern_setitimer() acquires process mutex, but
looses a race and kern_setitimer() gets the process mutex before the
callout.  Then, assuming that new specified struct itimerval has
it_interval zero, but it_value non-zero, the callout, after it starts
executing again, clears p->p_realtimer.it_value, but kern_setitimer()
already rescheduled the callout.

As the result of the race, both p_realtimer is zero, and the callout
is rescheduled. Then, in the exit1(), the exit code sees that it_value
is zero and does not even try to stop the callout. This allows the
struct proc to be reused and eventually the armed callout is
re-initialized.  The consequence is the corrupted callwheel tailq.

Use process mutex to interlock the callout start, which fixes the race.

Reported and tested by:	pho
Reviewed by:	jhb
MFC after:	2 weeks
2012-12-04 20:49:39 +00:00
Attilio Rao
324e57150d userret() already checks for td_locks when INVARIANTS is enabled, so
there is no need to check if Giant is acquired after it.

Reviewed by:	kib
MFC after:	1 week
2012-09-08 18:27:11 +00:00
Konstantin Belousov
02c6fc2114 Add a sysctl kern.pid_max, which limits the maximum pid the system is
allowed to allocate, and corresponding tunable with the same
name. Note that existing processes with higher pids are left intact.

MFC after:	1 week
2012-08-15 15:56:21 +00:00
Pawel Jakub Dawidek
0a7007b98f The falloc() function obtains two references to newly created 'fp'.
On success we have to drop one after procdesc_finit() and on failure
we have to close allocated slot with fdclose(), which also drops one
reference for us and drop the remaining reference with fdrop().

Without this change closing process descriptor didn't result in killing
pdfork(2)ed child.

Reviewed by:	rwatson
MFC after:	1 month
2012-06-19 22:21:59 +00:00
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
ab27d5d88a Fix panic with RACCT that could occur in low memory (or out of swap)
situations, due to fork1() calling racct_proc_exit() without calling
racct_proc_fork() first.

Submitted by:	Mateusz Guzik <mjguzik at gmail dot com> (earlier version)
Reviewed by:	Mateusz Guzik <mjguzik at gmail dot com>
2012-05-22 15:58:27 +00:00
Konstantin Belousov
1d7ca9bb8e Currently, the debugger attached to the process executing vfork() does
not get syscall exit notification until the child performed exec of
exit.  Swap the order of doing ptracestop() and waiting for P_PPWAIT
clearing, by postponing the wait into syscallret after ptracestop()
notification is done.

Reported, tested and reviewed by:	Dmitry Mikulin <dmitrym juniper net>
MFC after:	 2 weeks
2012-02-27 21:10:10 +00:00
Konstantin Belousov
dcd432817e Allow the parent to gather the exit status of the children reparented
to the debugger.  When reparenting for debugging, keep the child in
the new orphan list of old parent.  When looping over the children in
kern_wait(), iterate over both children list and orphan list to search
for the process by pid.

Submitted by:	Dmitry Mikulin <dmitrym juniper.net>
MFC after:	2 weeks
2012-02-23 11:50:23 +00:00
Konstantin Belousov
db3273398b Mark the automatically attached child with PL_FLAG_CHILD in struct
lwpinfo flags, for PT_FOLLOWFORK auto-attachment.

In collaboration with:	Dmitry Mikulin <dmitrym juniper net>
MFC after:	 1 week
2012-02-10 00:02:13 +00:00
Edward Tomasz Napierala
2d8696d1e8 Move some code inside the racct_proc_fork(); it spares a few lock operations
and it's more logical this way.

MFC after:	3 days
2011-10-03 17:40:55 +00:00
Edward Tomasz Napierala
72a401d918 Fix another bug introduced in r225641, which caused rctl to access certain
fields in 'struct proc' before they got initialized in do_fork().

MFC after:	3 days
2011-10-03 16:23:20 +00:00
Edward Tomasz Napierala
1dbf9dcc20 Fix error handling bug that would prevent MAC structures from getting
freed properly if resource limit got exceeded.

Approved by:	re (kib)
2011-09-17 20:48:49 +00:00
Edward Tomasz Napierala
b38520f09c Fix long-standing thinko regarding maxproc accounting. Basically,
we were accounting the newly created process to its parent instead
of the child itself.  This caused problems later, when the child
changed its credentials - the per-uid, per-jail etc counters were
not properly updated, because the maxproc counter in the child
process was 0.

Approved by:	re (kib)
2011-09-17 19:55:32 +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
Jonathan Anderson
cfb5f76865 Add experimental support for process descriptors
A "process descriptor" file descriptor is used to manage processes
without using the PID namespace. This is required for Capsicum's
Capability Mode, where the PID namespace is unavailable.

New system calls pdfork(2) and pdkill(2) offer the functional equivalents
of fork(2) and kill(2). pdgetpid(2) allows querying the PID of the remote
process for debugging purposes. The currently-unimplemented pdwait(2) will,
in the future, allow querying rusage/exit status. In the interim, poll(2)
may be used to check (and wait for) process termination.

When a process is referenced by a process descriptor, it does not issue
SIGCHLD to the parent, making it suitable for use in libraries---a common
scenario when using library compartmentalisation from within large
applications (such as web browsers). Some observers may note a similarity
to Mach task ports; process descriptors provide a subset of this behaviour,
but in a UNIX style.

This feature is enabled by "options PROCDESC", but as with several other
Capsicum kernel features, is not enabled by default in GENERIC 9.0.

Reviewed by: jhb, kib
Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-18 22:51:30 +00:00
Konstantin Belousov
f49d820256 Implement an RFTSIGZMB flag to rfork(2) to specify a signal that is
delivered to parent when the child exists.

Submitted by:	Petr Salinger <Petr.Salinger seznam cz> (Debian/kFreeBSD)
MFC after:	1 week
X-MFC-note:	bump __FreeBSD_version
2011-07-12 20:37:18 +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
Edward Tomasz Napierala
097055e26d Add racct. It's an API to keep per-process, per-jail, per-loginclass
and per-loginclass resource accounting information, to be used by the new
resource limits code.  It's connected to the build, but the code that
actually calls the new functions will come later.

Sponsored by:	The FreeBSD Foundation
Reviewed by:	kib (earlier version)
2011-03-29 17:47:25 +00:00
John Baldwin
8e6fa660f2 Fix some locking nits with the p_state field of struct proc:
- Hold the proc lock while changing the state from PRS_NEW to PRS_NORMAL
  in fork to honor the locking requirements.  While here, expand the scope
  of the PROC_LOCK() on the new process (p2) to avoid some LORs.  Previously
  the code was locking the new child process (p2) after it had locked the
  parent process (p1).  However, when locking two processes, the safe order
  is to lock the child first, then the parent.
- Fix various places that were checking p_state against PRS_NEW without
  having the process locked to use PROC_LOCK().  Every place was already
  locking the process, just after the PRS_NEW check.
- Remove or reduce the use of PROC_SLOCK() for places that were checking
  p_state against PRS_NEW.  The PROC_LOCK() alone is sufficient for reading
  the current state.
- Reorder fill_kinfo_proc() slightly so it only acquires PROC_SLOCK() once.

MFC after:	1 week
2011-03-24 18:40:11 +00:00
Dmitry Chagin
e5d81ef1b5 Extend struct sysvec with new method sv_schedtail, which is used for an
explicit process at fork trampoline path instead of eventhadler(schedtail)
invocation for each child process.

Remove eventhandler(schedtail) code and change linux ABI to use newly added
sysvec method.

While here replace explicit comparing of module sysentvec structure with the
newly created process sysentvec to detect the linux ABI.

Discussed with:	kib

MFC after:	2 Week
2011-03-08 19:01:45 +00:00
Dmitry Chagin
7705d4b24a Introduce preliminary support of the show description of the ABI of
traced process by adding two new events which records value of process
sv_flags to the trace file at process creation/execing/exiting time.

MFC after:	1 Month.
2011-02-25 22:05:33 +00:00
Konstantin Belousov
6fa39a7327 Allow debugger to specify that children of the traced process should be
automatically traced. Extend the ptrace(PL_LWPINFO) to report that child
just forked.

Reviewed by:	davidxu, jhb
MFC after:	2 weeks
2011-01-25 10:59:21 +00:00
John Baldwin
22d19207e9 - Move sched_fork() later in fork() after the various sections of the new
thread and proc have been copied and zeroed from the old thread and
  proc.  Otherwise attempts to modify thread or process data in sched_fork()
  could be undone.
- Don't copy td_{base,}_user_pri from the old thread to the new thread in
  sched_fork_thread() in ULE.  This is already done courtesy the bcopy()
  of the thread copy region.
- Always initialize the real priority (td_priority) of new threads to the
  new thread's base priority (td_base_pri) to avoid bogusly inheriting a
  borrowed priority from the parent thread.

MFC after:	2 weeks
2011-01-06 22:24:00 +00:00
Edward Tomasz Napierala
3e73ff1e94 Finishing touches to fork1() - ANSIfy missed function definition, style(9)
fixes, removal of few comments that didn't really make sense and addition
of fork_findpid() locking requirements.
2011-01-02 12:16:57 +00:00
Edward Tomasz Napierala
afd01097a0 Refactor fork1() to make it easier to follow. No functional changes.
Reviewed by:	kib (earlier version)
Tested by:	pho
2010-12-10 08:33:56 +00:00
David Xu
acbe332a58 MFp4:
It is possible a lower priority thread lending priority to higher priority
thread, in old code, it is ignored, however the lending should always be
recorded, add field td_lend_user_pri to fix the problem, if a thread does
not have borrowed priority, its value is PRI_MAX.

MFC after: 1 week
2010-12-09 02:42:02 +00:00
Edward Tomasz Napierala
087bfb0e6b Add a KASSERT to make it obvious when fork_norfproc() is to be called,
and set *procp to NULL in all cases.  Previously, it was not being set
in the ERESTART case.  This is effectively no-op, since its value is
ignored by callers in the error case.

Reviewed by:	kib@
2010-12-06 19:15:38 +00:00
Edward Tomasz Napierala
f68c74bbd3 Fix style bug introduced by previous commit. 2010-12-06 16:45:36 +00:00
Edward Tomasz Napierala
1d845e8638 Improve readability by factoring out the !RFPROC case. While here,
turn K&R function definitions into ANSI.  No functional changes.

Reviewed by:	kib@
2010-12-06 16:39:18 +00:00
John Baldwin
d680caab73 - When disabling ktracing on a process, free any pending requests that
may be left.  This fixes a memory leak that can occur when tracing is
  disabled on a process via disabling tracing of a specific file (or if
  an I/O error occurs with the tracefile) if the process's next system
  call is exit().  The trace disabling code clears p_traceflag, so exit1()
  doesn't do any KTRACE-related cleanup leading to the leak.  I chose to
  make the free'ing of pending records synchronous rather than patching
  exit1().
- Move KTRACE-specific logic out of kern_(exec|exit|fork).c and into
  kern_ktrace.c instead.  Make ktrace_mtx private to kern_ktrace.c as a
  result.

MFC after:	1 month
2010-10-21 19:17:40 +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
Rui Paulo
d3555b6fc2 Fix two bugs in DTrace:
* when the process exits, remove the associated USDT probes
* when the process forks, duplicate the USDT probes.

Sponsored by:	The FreeBSD Foundation
2010-09-09 09:58:05 +00:00
Rui Paulo
79856499bd Add an extra comment to the SDT probes definition. This allows us to get
use '-' in probe names, matching the probe names in Solaris.[1]

Add userland SDT probes definitions to sys/sdt.h.

Sponsored by:	The FreeBSD Foundation
Discussed with:	rwaston [1]
2010-08-22 11:18:57 +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
b6b2d1bf88 Dispose the kernel stack of the proper thread.
Submitted by:	alc
MFC after:	1 week
2009-08-29 18:01:02 +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
Jamie Gritton
7afcbc18b3 Remove the interim vimage containers, struct vimage and struct procg,
and the ioctl-based interface that supported them.

Approved by:	re (kib), bz (mentor)
2009-07-17 14:48:21 +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