Commit Graph

152 Commits

Author SHA1 Message Date
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
David Xu
d65f1abca7 Implement syscall clock_getcpuclockid2, so we can get a clock id
for process, thread or others we want to support.
Use the syscall to implement POSIX API clock_getcpuclock and
pthread_getcpuclockid.

PR:	168417
2012-08-17 02:26:31 +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
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
Robert Watson
885868cd8f Remove VOP_LEASE and supporting functions. This hasn't been used since
the removal of NQNFS, but was left in in case it was required for NFSv4.
Since our new NFSv4 client and server can't use it for their
requirements, GC the old mechanism, as well as other unused lease-
related code and interfaces.

Due to its impact on kernel programming and binary interfaces, this
change should not be MFC'd.

Proposed by:    jeff
Reviewed by:    jeff
Discussed with: rmacklem, zach loafman @ isilon
2009-04-10 10:52:19 +00:00
Colin Percival
3f935cf342 Correctly sanity-check timer IDs. [SA-09:06]
Limit the size of malloced buffer when dumping environment
variables. [EN-09:01]

Approved by:	so (cperciva)
Approved by:	re (kensmith)
Security:	FreeBSD-SA-09:06.ktimer
Errata:		FreeBSD-EN-09:01.kenv
2009-03-23 00:00:50 +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
David Xu
d6b6592ec0 In realtimer_delete(), clear timer's value and interval to tell
realtimer_expire() to not rearm the timer, otherwise there is a chance
that a callout will be left there and be tiggered in future unexpectly.

Bug reported by: tegge@
2008-10-20 02:37:53 +00:00
David Xu
0e17ccbe36 Make sure reading td_runtime in critical section since thread may be
preempted and td_runtime will be modified.
2008-01-18 13:00:28 +00:00
David Xu
00d6ac63cd Add POSIX clock id CLOCK_THREAD_CPUTIME_ID, this can be used to measure
per-thread runtime in user code.
2008-01-18 07:04:42 +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
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
Robert Watson
c14d15ae3e Remove MAC Framework access control check entry points made redundant with
the introduction of priv(9) and MAC Framework entry points for privilege
checking/granting.  These entry points exactly aligned with privileges and
provided no additional security context:

- mac_check_sysarch_ioperm()
- mac_check_kld_unload()
- mac_check_settime()
- mac_check_system_nfsd()

Add mpo_priv_check() implementations to Biba and LOMAC policies, which,
for each privilege, determine if they can be granted to processes
considered unprivileged by those two policies.  These mostly, but not
entirely, align with the set of privileges granted in jails.

Obtained from:	TrustedBSD Project
2007-04-22 15:31:22 +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
843b99c6f7 - Remove third parameter of itimer_find, the parameter is always zero.
- Call callout_drain on deleting POSIX timer.
- Use kern_timer_delete in exiting hook.
2006-11-28 03:24:34 +00:00
Tom Rhodes
6aeb05d7be Merge posix4/* into normal kernel hierarchy.
Reviewed by:	glanced at by jhb
Approved by:	silence on -arch@ and -standards@
2006-11-11 16:26:58 +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
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
Poul-Henning Kamp
94d67e0fb8 Move tz_minuteswest and tz_dsttime to subr_clock.c 2006-10-02 16:06:26 +00:00
Poul-Henning Kamp
f645b0b51c First part of a little cleanup in the calendar/timezone/RTC handling.
Move relevant variables to <sys/clock.h> and fix #includes as necessary.

Use libkern's much more time- & spamce-efficient BCD routines.
2006-10-02 12:59:59 +00:00
Alexander Leidinger
993182e57c - Change process_exec function handlers prototype to include struct
image_params arg.
- Change struct image_params to include struct sysentvec pointer and
  initialize it.
- Change all consumers of process_exit/process_exec eventhandlers to
  new prototypes (includes splitting up into distinct exec/exit functions).
- Add eventhandler to userret.

Sponsored by:		Google SoC 2006
Submitted by:		rdivacky
Parts suggested by:	jhb (on hackers@)
2006-08-15 12:10:57 +00:00
David Xu
aff5bcb1b2 INT_MAX is defined in file sys/limits.h, include the file now. 2006-08-02 07:34:51 +00:00
David Xu
61d3a4efc2 Let kernel POSIX timer code and mqueue code to use integer as a resource
handle, the timer_t and mqd_t types will be a pointer which userland
will define it.
2006-03-01 06:29:34 +00:00
David Xu
3e70c6f047 Fix compiling warning on 64 bits system. 2005-12-09 13:16:48 +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
David Xu
77e718f773 1. Set timer configuration values for sysconf().
2. Set overrun limit to INT_MAX, report ERANGE error if overrun will be
   greater than INT_MAX.
2005-12-01 07:56:15 +00:00
Robert Watson
5e758b9561 Add several aliases for existing clockid_t names to indicate that the
application wishes to request high precision time stamps be returned:

Alias                           Existing

CLOCK_REALTIME_PRECISE          CLOCK_REALTIME
CLOCK_MONOTONIC_PRECISE         CLOCK_MONOTONIC
CLOCK_UPTIME_PRECISE            CLOCK_UPTIME

Add experimental low-precision clockid_t names corresponding to these
clocks, but implemented using cached timestamps in kernel rather than
a full time counter query.  This offers a minimum update rate of 1/HZ,
but in practice will often be more frequent due to the frequency of
time stamping in the kernel:

New clockid_t name              Approximates existing clockid_t

CLOCK_REALTIME_FAST             CLOCK_REALTIME
CLOCK_MONOTONIC_FAST            CLOCK_MONOTONIC
CLOCK_UPTIME_FAST               CLOCK_UPTIME

Add one additional new clockid_t, CLOCK_SECOND, which returns the
current second without performing a full time counter query or cache
lookup overhead to make sure the cached timestamp is stable.  This is
intended to support very low granularity consumers, such as time(3).

The names, visibility, and implementation of the above are subject
to change, and will not be MFC'd any time soon.  The goal is to
expose lower quality time measurement to applications willing to
sacrifice accuracy in performance critical paths, such as when taking
time stamps for the purpose of rescheduling select() and poll()
timeouts.  Future changes might include retrofitting the time counter
infrastructure to allow the "fast" time query mechanisms to use a
different time counter, rather than a cached time counter (i.e.,
TSC).

NOTE: With different underlying time mechanisms exposed, using
different time query mechanisms in the same application may result in
relative non-monoticity or the appearance of clock stalling for a
single clockid_t, as a cached time stamp queried after a precision
time stamp lookup may be "before" the time returned by the earlier
live time counter query.
2005-11-27 00:55:18 +00:00
Andre Oppermann
5eefd88949 Add CLOCK_UPTIME to clock_gettime(2) reporting the current
uptime measured in SI seconds.

Sponsored by:	TCP/IP Optimization Fundraise 2005
2005-11-18 16:51:13 +00:00
David Xu
8f0371f19d Fix name compatible problem with POSIX standard. the sigval_ptr and
sigval_int really should be sival_ptr and sival_int.
Also sigev_notify_function accepts a union sigval value but not a
pointer.
2005-11-04 09:41:00 +00:00
David Xu
6d7b314b14 Cleanup some signal interfaces. Now the tdsignal function accepts
both proc pointer and thread pointer, if thread pointer is NULL,
tdsignal automatically finds a thread, otherwise it sends signal
to given thread.
Add utility function psignal_event to send a realtime sigevent
to a process according to the delivery requirement specified in
struct sigevent.
2005-11-03 04:49:16 +00:00
David Xu
56c06c4b67 Let itimer store itimerspec instead of itimerval, so I don't have to
convert to or from timeval frequently.

Introduce function itimer_accept() to ack a timer signal in signal
acceptance code, this allows us to return more fresh overrun counter
than at signal generating time. while POSIX says:
"the value returned by timer_getoverrun() shall apply to the most
recent expiration signal delivery or acceptance for the timer,.."
I prefer returning it at acceptance time.

Introduce SIGEV_THREAD_ID notification mode, it is used by thread
libary to request kernel to deliver signal to a specified thread,
and in turn, the thread library may use the mechanism to implement
SIGEV_THREAD which is required by POSIX.

Timer signal is managed by timer code, so it can not fail even if
signal queue is full filled by sigqueue syscall.
2005-10-30 02:56:08 +00:00
David Xu
fe80a39034 Don't touch last overrun if signal was already on queue. 2005-10-23 22:59:33 +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
Paul Saab
f0b479cd75 Implement 32bit wrappers for clock_gettime, clock_settime, and
clock_getres.
2005-10-15 02:54:18 +00:00
John Baldwin
b88ec951e1 Implement kern_adjtime(), kern_readv(), kern_sched_rr_get_interval(),
kern_settimeofday(), and kern_writev() to allow for further stackgap
reduction in the compat ABIs.
2005-03-31 22:51:18 +00:00
John Baldwin
5e85ac176f If the pointer to the new itimerval is NULL in kern_setitimer(), just
read the old value via kern_getitimer().
2005-02-07 21:45:48 +00:00
John Baldwin
c90110d639 Various and sundry style fixes. 2005-02-07 18:38:29 +00:00
Maxim Sobolev
cfa0efe7ab Split out kernel side of {get,set}itimer(2) into two parts: the first that
pops data from the userland and pushes results back and the second which does
actual processing. Use the latter to eliminate stackgap in the linux wrappers
of those syscalls.

MFC after:	2 weeks
2005-01-25 21:28:28 +00:00
Paul Saab
efa42cbc93 move kern_nanosleep to sys/syscallsubr.h
Requested by:	jhb
2005-01-19 18:09:50 +00:00
Paul Saab
7fdf2c856f - rename nanosleep1 to kern_nanosleep
- Add a 32bit syscall entry for nanosleep

Reviewed by:	peter
Obtained from:	Yahoo!
2005-01-19 17:44:59 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +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
Kelly Yancey
de0a924120 Update previous commit to:
* Obtain/release schedlock around calls to calcru.
  * Sort switch cases which do not cascade per style(9).
  * Sort local variables per style(9).
  * Remove "superfluous" whitespace.
  * Cleanup handling of NULL uap->tp in clock_getres().  It would probably
    be better to return EFAULT like clock_gettime() does by passing the
    pointer to copyout(), but I presume it was written to not fail on
    purpose in the original code.  I'll defer to -standards on this one.

Reported by:	bde
2004-06-21 22:34:57 +00:00
Kelly Yancey
b8817154c3 Implement CLOCK_VIRTUAL and CLOCK_PROF for clock_gettime(2) and
clock_getres(2).

Reviewed by:	phk
PR:		23304
2004-06-17 23:12:12 +00:00
Warner Losh
7f8a436ff2 Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core
2004-04-05 21:03:37 +00:00
Alfred Perlstein
6ff7636ea5 constify the second args to timevaladd() and timevalsub(). 2003-10-26 02:19:00 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
John Baldwin
5499ea019d Wait for the real interval timer callout handler to finish executing if it
is currently executing when we try to remove it in exit1().  Without this,
it was possible for the callout to bogusly rearm itself and eventually
refire after the process had been free'd resulting in a panic.

PR:		kern/51964
Reported by:	Jilles Tjoelker <jilles@stack.nl>
Reviewed by:	tegge, bde
2003-06-09 21:46:22 +00:00