Commit Graph

326 Commits

Author SHA1 Message Date
Konstantin Belousov
7c6d401c75 The control terminal revocation at the session leader exit does not
correctly checks for reclaimed vnode, possibly calling VOP_REVOKE for
such vnode. If the terminal is already revoked, or devfs mount was
forcibly unmounted, the revocation of doomed ctty vnode causes panic.

Reported and tested by:	lstewart
Approved by:	re (kensmith)
MFC after:	2 weeks
2009-07-09 18:54:38 +00:00
Robert Watson
2ef24dde7c udit the 'options' argument to wait4(2).
Approved by:	re (kib)
MFC after:	3 days
2009-07-01 12:36:10 +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
eaaaf1906b Perform some more cleanups to in-kernel session handling.
The code that was in place in exit1() was mainly based on code from the
old TTY layer. The main reason behind this, was because at one moment I
ran a system that had two TTY layers in place at the same time. It is
now sufficient to do the following:

- Remove references from the session structure to the TTY vnode and the
  session leader.

- If we have a controlling TTY and the session used by the TTY is equal
  to our session, send the SIGHUP.

- If we have a vnode to the controlling TTY which has not been revoked,
  revoke it.

While there, change sys/kern/tty.c to use s_ttyp in the comparison
instead of s_ttyvp. It should not make any difference, because s_ttyvp
can only become null when the session leader already left, but it's
nicer to compare against the proper value.
2009-06-15 20:45:51 +00:00
Ed Schouten
9c373a81a3 Make tcsetsid(3) work on revoked TTYs.
Right now the only way to make tcsetsid(3)/TIOCSCTTY work, is by
ensuring the session leader is dead. This means that an application that
catches SIGHUPs and performs a sleep prevents us from assigning a new
session leader.

Change the code to make it work on revoked TTYs as well. This allows us
to change init(8) to make the shutdown script run in a more clean
environment.
2009-06-15 19:17:52 +00:00
Robert Watson
324fb6be0f Move zombie-reaping code out of kern_wait() and into its own function,
proc_reap().
Reviewed by:	jhb
MFC after:	3 days
Sponsored by:	Google, Inc.
2009-06-08 15:26:09 +00:00
Robert Watson
bcf11e8d00 Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with:	pjd
2009-06-05 14:55:22 +00:00
Jamie Gritton
0304c73163 Add hierarchical jails. A jail may further virtualize its environment
by creating a child jail, which is visible to that jail and to any
parent jails.  Child jails may be restricted more than their parents,
but never less.  Jail names reflect this hierarchy, being MIB-style
dot-separated strings.

Every thread now points to a jail, the default being prison0, which
contains information about the physical system.  Prison0's root
directory is the same as rootvnode; its hostname is the same as the
global hostname, and its securelevel replaces the global securelevel.
Note that the variable "securelevel" has actually gone away, which
should not cause any problems for code that properly uses
securelevel_gt() and securelevel_ge().

Some jail-related permissions that were kept in global variables and
set via sysctls are now per-jail settings.  The sysctls still exist for
backward compatibility, used only by the now-deprecated jail(2) system
call.

Approved by:	bz (mentor)
2009-05-27 14:11:23 +00:00
Marko Zec
29b02909eb Introduce a new virtualization container, provisionally named vprocg, to hold
virtualized instances of hostname and domainname, as well as a new top-level
virtualization struct vimage, which holds pointers to struct vnet and struct
vprocg.  Struct vprocg is likely to become replaced in the near future with
a new jail management API import.

As a consequence of this change, change struct ucred to point to a struct
vimage, instead of directly pointing to a vnet.

Merge vnet / vimage / ucred refcounting infrastructure from p4 / vimage
branch.

Permit kldload / kldunload operations to be executed only from the default
vimage context.

This change should have no functional impact on nooptions VIMAGE kernel
builds.

Reviewed by:	bz
Approved by:	julian (mentor)
2009-05-08 14:11:06 +00:00
Konstantin Belousov
6fae832ad7 Fix typo.
Noted by:	jhb
MFC after:	2 weeks
2009-04-20 15:10:03 +00:00
Konstantin Belousov
007abb3d0f On the exit of the child process which parent either set SA_NOCLDWAIT
or ignored SIGCHLD, unconditionally wake up the parent instead of doing
this only when the child is a last child.

This brings us in line with other U**xes that support SA_NOCLDWAIT. If
the parent called waitpid(childpid), then exit of the child should wake
up the parent immediately instead of forcing it to wait for all children
to exit.

Reported by:	Alan Ferrency <alan pair com>
Submitted by:	Jilles Tjoelker <jilles stack nl>
PR:	108390
MFC after:	2 weeks
2009-04-20 14:34:55 +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
aeb325719a Several threads in a process may do vfork() simultaneously. Then, all
parent threads sleep on the parent' struct proc until corresponding
child releases the vmspace. Each sleep is interlocked with proc mutex of
the child, that triggers assertion in the sleepq_add(). The assertion
requires that at any time, all simultaneous sleepers for the channel use
the same interlock.

Silent the assertion by using conditional variable allocated in the
child. Broadcast the variable event on exec() and exit().

Since struct proc * sleep wait channel is overloaded for several
unrelated events, I was unable to remove wakeups from the places where
cv_broadcast() is added, except exec().

Reported and tested by:	ganbold
Suggested and reviewed by:	jhb
MFC after:	2 week
2008-12-05 20:50:24 +00:00
Bjoern A. Zeeb
413628a7e3 MFp4:
Bring in updated jail support from bz_jail branch.

This enhances the current jail implementation to permit multiple
addresses per jail. In addtion to IPv4, IPv6 is supported as well.
Due to updated checks it is even possible to have jails without
an IP address at all, which basically gives one a chroot with
restricted process view, no networking,..

SCTP support was updated and supports IPv6 in jails as well.

Cpuset support permits jails to be bound to specific processor
sets after creation.

Jails can have an unrestricted (no duplicate protection, etc.) name
in addition to the hostname. The jail name cannot be changed from
within a jail and is considered to be used for management purposes
or as audit-token in the future.

DDB 'show jails' command was added to aid debugging.

Proper compat support permits 32bit jail binaries to be used on 64bit
systems to manage jails. Also backward compatibility was preserved where
possible: for jail v1 syscalls, as well as with user space management
utilities.

Both jail as well as prison version were updated for the new features.
A gap was intentionally left as the intermediate versions had been
used by various patches floating around the last years.

Bump __FreeBSD_version for the afore mentioned and in kernel changes.

Special thanks to:
- Pawel Jakub Dawidek (pjd) for his multi-IPv4 patches
  and Olivier Houchard (cognet) for initial single-IPv6 patches.
- Jeff Roberson (jeff) and Randall Stewart (rrs) for their
  help, ideas and review on cpuset and SCTP support.
- Robert Watson (rwatson) for lots and lots of help, discussions,
  suggestions and review of most of the patch at various stages.
- John Baldwin (jhb) for his help.
- Simon L. Nielsen (simon) as early adopter testing changes
  on cluster machines as well as all the testers and people
  who provided feedback the last months on freebsd-jail and
  other channels.
- My employer, CK Software GmbH, for the support so I could work on this.

Reviewed by:	(see above)
MFC after:	3 months (this is just so that I get the mail)
X-MFC Before:   7.2-RELEASE if possible
2008-11-29 14:32:14 +00:00
David Xu
904c5ec4e3 Move per-thread userland debugging flags into seperated field,
this eliminates some problems of locking, e.g, a thread lock is needed
but can not be used at that time. Only the process lock is needed now
for new field.
2008-10-15 06:31:37 +00:00
David Xu
3eb8b8bbeb Don't remove queued SIGCHLD if options contain WNOWAIT, so other
threads still can be notified by the signal.
2008-08-29 01:34:05 +00:00
Konstantin Belousov
cbc158449b Implement WNOWAIT flag for wait4(2). It specifies that process whose status
is returned shall be kept in the waitable state.
Add WSTOPPED as an alias for WUNTRACED.

Submitted by:	Jukka Ukkonen <jau at iki fi>
PR:	standards/116221
MFC after:	2 weeks
2008-08-26 12:37:16 +00:00
Ed Schouten
bc093719ca Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

  The old TTY layer has a driver model that is not abstract enough to
  make it friendly to use. A good example is the output path, where the
  device drivers directly access the output buffers. This means that an
  in-kernel PPP implementation must always convert network buffers into
  TTY buffers.

  If a PPP implementation would be built on top of the new TTY layer
  (still needs a hooks layer, though), it would allow the PPP
  implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

  With the old TTY layer, it isn't entirely safe to destroy TTY's from
  the system. This implementation has a two-step destructing design,
  where the driver first abandons the TTY. After all threads have left
  the TTY, the TTY layer calls a routine in the driver, which can be
  used to free resources (unit numbers, etc).

  The pts(4) driver also implements this feature, which means
  posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

  One of the major improvements is the per-TTY mutex, which is expected
  to improve scalability when compared to the old Giant locking.
  Another change is the unbuffered copying to userspace, which is both
  used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from:		//depot/projects/mpsafetty/...
Approved by:		philip (ex-mentor)
Discussed:		on the lists, at BSDCan, at the DevSummit
Sponsored by:		Snow B.V., the Netherlands
dcons(4) fixed by:	kan
2008-08-20 08:31:58 +00:00
John Birrell
5d217f173c Add DTrace 'proc' provider probes using the Statically Defined Trace
(sdt) mechanism.
2008-05-24 06:22:16 +00:00
Poul-Henning Kamp
4218a7310b In abort2(2): Accept a NULL arg pointer if nargs == 0 2008-03-22 16:32:52 +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
Kris Kennaway
e17660e79c Switch from conditionally dropping Giant in exit1() to asserting it is
not held, which appears to be always true.
2008-02-17 15:28:28 +00:00
Attilio Rao
22db15c06f VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
2008-01-13 14:44:15 +00:00
Julian Elischer
7ab24ea3b9 Introduce a way to make pure kernal threads.
kthread_add() takes the same parameters as the old kthread_create()
plus a pointer to a process structure, and adds a kernel thread
to that process.

kproc_kthread_add() takes the parameters for kthread_add,
plus a process name and a pointer to a pointer to a process instead of just
a pointer, and if the proc * is NULL, it creates the process to the
specifications required, before adding the thread to it.

All other old kthread_xxx() calls return, but act on (struct thread *)
instead of (struct proc *). One reason to change the name is so that
any old kernel modules that are lying around and expect kthread_create()
to make a process will not just accidentally link.

fix top to show  kernel threads by their thread name in -SH mode
add a tdnam formatting option to ps to show thread names.

make all idle threads actual kthreads and put them into their own idled process.
make all interrupt threads kthreads and put them in an interd process
(mainly for aesthetic and accounting reasons)
rename proc 0 to be 'kernel' and it's swapper thread is now 'swapper'

man page fixes to follow.
2007-10-26 08:00:41 +00:00
Robert Watson
30d239bc4c Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
John Baldwin
34a9edafbc Improve the ktrace locking somewhat to reduce overhead:
- Depessimize userret() in kernels where KTRACE is enabled by doing an
  unlocked check of the per-process queue of pending events before
  acquiring any locks.  Previously ktr_userret() unconditionally acquired
  the global ktrace_sx lock on every return to userland for every thread,
  even if ktrace wasn't enabled for the thread.
- Optimize the locking in exit() to first perform an unlocked read of
  p_traceflag to see if ktrace is enabled and only acquire locks and
  teardown ktrace if the test succeeds.  Also, explicitly disable tracing
  before draining any pending events so the pending events actually get
  written out.  The unlocked read is safe because proc lock is acquired
  earlier after single-threading so p_traceflag can't change between then
  and this check (well, it can currently due to a bug in ktrace I will fix
  next, but that race existed prior to this change as well).

Reviewed by:	rwatson
2007-06-13 20:01:42 +00:00
Attilio Rao
a1fe14bc33 rufetch and calcru sometimes should be called atomically together.
This patch fixes places where they should be called atomically changing
their locking requirements (both assume per-proc spinlock held) and
introducing rufetchcalc which wrappers both calls to be performed in
atomic way.

Reviewed by: jeff
Approved by: jeff (mentor)
2007-06-09 21:48:44 +00:00
Attilio Rao
a140976eb4 The current rusage code show peculiar problems:
- Unsafeness on ruadd() in thread_exit()
- Unatomicity of thread_exiit() in the exit1() operations

This patch addresses these problems allocating p_fd as part of the
process and modifying the way it is accessed.

A small chunk of this patch, resolves a race about p_state in kern_wait(),
since we have to be sure about the zombif-ing process.

Submitted by: jeff
Approved by: jeff (mentor)
2007-06-09 18:56:11 +00:00
Robert Watson
faef53711b Move per-process audit state from a pointer in the proc structure to
embedded storage in struct ucred.  This allows audit state to be cached
with the thread, avoiding locking operations with each system call, and
makes it available in asynchronous execution contexts, such as deep in
the network stack or VFS.

Reviewed by:	csjp
Approved by:	re (kensmith)
Obtained from:	TrustedBSD Project
2007-06-07 22:27:15 +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
1c4bcd050a - Move rusage from being per-process in struct pstats to per-thread in
td_ru.  This removes the requirement for per-process synchronization in
   statclock() and mi_switch().  This was previously supported by
   sched_lock which is going away.  All modifications to rusage are now
   done in the context of the owning thread.  reads proceed without locks.
 - Aggregate exiting threads rusage in thread_exit() such that the exiting
   thread's rusage is not lost.
 - Provide a new routine, rufetch() to fetch an aggregate of all rusage
   structures from all threads in a process.  This routine must be used
   in any place requiring a rusage from a process prior to it's exit.  The
   exited process's rusage is still available via p_ru.
 - Aggregate tick statistics only on demand via rufetch() or when a thread
   exits.  Tick statistics are kept in the thread and protected by sched_lock
   until it exits.

Initial patch by:	attilio
Reviewed by:		attilio, bde (some objections), arch (mostly silent)
2007-06-01 01:12:45 +00:00
John Baldwin
1bba2a940b Move cpu_exit() earlier in exit1() to close a race between
SIGCHLD/kevent(2) notification of process termination and wait().  Now
we no longer drop locks between sending the notification and marking
the process as a zombie.  Previously, if another process attempted to do
a wait() with W_NOHANG after receiving a SIGCHLD or kevent and locked
the process while the exiting thread was in cpu_exit(), then wait() would
fail to find the process, which is quite astonishing to the process
calling wait().

MFC after:	3 days
2007-05-14 22:21:58 +00:00
John Baldwin
aa89d8cd52 Rename the 'mtx_object', 'rw_object', and 'sx_object' members of mutexes,
rwlocks, and sx locks to 'lock_object'.
2007-03-21 21:20:51 +00:00
Robert Watson
873fbcd776 Further system call comment cleanup:
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
  "syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
2007-03-05 13:10:58 +00:00
Robert Watson
0c14ff0eb5 Remove 'MPSAFE' annotations from the comments above most system calls: all
system calls now enter without Giant held, and then in some cases, acquire
Giant explicitly.

Remove a number of other MPSAFE annotations in the credential code and
tweak one or two other adjacent comments.
2007-03-04 22:36:48 +00:00
David Xu
ff7668079f Move sigqueue_take() call into proc_reparent(), this fixed bugs where
proc_reparent() is called but sigqueue_take() is forgotten.
2006-10-25 06:18:04 +00:00
David Xu
e94cc4ac30 Protect sigqueue_take() call by child process's lock, it fixed a
potential race with ptrace 'attach' which changes parent of the
child process.
2006-10-24 12:04:21 +00:00
Robert Watson
aed5570872 Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h.  sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA
2006-10-22 11:52:19 +00:00
David Xu
f71e748d89 Since revision 1.333 of kern_sig.c no longer uses P_WEXIT, the change
opened a race window which can cause memory leak in signal queue.
Here we free memory for signal queue when process state is set to
PRS_ZOMBIE.
2006-10-21 23:59:15 +00:00
Christian S.J. Peron
7ca6b7823d Back out one of the Giant removals from revision 1.272. Giant was not here to
protect the vnode, it was present to synchronize access to TTY session
information between exit(2) and the TTY code. While we are here, note that
Giant is required for TTY protection.

Clue from:	bde
Discussed with:	jhb
MFC after:	1 week
2006-09-13 15:47:53 +00:00
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