Commit Graph

189 Commits

Author SHA1 Message Date
Don Lewis
91e97a8266 In an SMP environment post-Giant it is no longer safe to blindly
dereference the struct sigio pointer without any locking.  Change
fgetown() to take a reference to the pointer instead of a copy of the
pointer and call SIGIO_LOCK() before copying the pointer and
dereferencing it.

Reviewed by:	rwatson
2002-10-03 02:13:00 +00:00
John Baldwin
551cf4e150 Rename the mutex thread and process states to use a more generic 'LOCK'
name instead.  (e.g., SLOCK instead of SMTX, TD_ON_LOCK() instead of
TD_ON_MUTEX())  Eventually a turnstile abstraction will be added that
will be shared with mutexes and other types of locks.  SLOCK/TDI_LOCK will
be used internally by the turnstile code and will not be specific to
mutexes.  Making the change now ensures that turnstiles can be dropped
in at a later date without affecting the ABI of userland applications.
2002-10-02 20:31:47 +00:00
Juli Mallett
1d9c56964d Back our kernel support for reliable signal queues.
Requested by:	rwatson, phk, and many others
2002-10-01 17:15:53 +00:00
Juli Mallett
1226f694e6 First half of implementation of ksiginfo, signal queues, and such. This
gets signals operating based on a TailQ, and is good enough to run X11,
GNOME, and do job control.  There are some intricate parts which could be
more refined to match the sigset_t versions, but those require further
evaluation of directions in which our signal system can expand and contract
to fit our needs.

After this has been in the tree for a while, I will make in kernel API
changes, most notably to trapsignal(9) and sendsig(9), to use ksiginfo
more robustly, such that we can actually pass information with our
(queued) signals to the userland.  That will also result in using a
struct ksiginfo pointer, rather than a signal number, in a lot of
kern_sig.c, to refer to an individual pending signal queue member, but
right now there is no defined behaviour for such.

CODAFS is unfinished in this regard because the logic is unclear in
some places.

Sponsored by:	New Gold Technology
Reviewed by:	bde, tjr, jake [an older version, logic similar]
2002-09-30 20:20:22 +00:00
Julian Elischer
71fad9fdee Completely redo thread states.
Reviewed by:	davidxu@freebsd.org
2002-09-11 08:13:56 +00:00
Julian Elischer
9f189ade99 Clear up confusion in ugly code. ^T gave wrong results for RSS.
I misinterpretted this code when changing it to handle threads.
(there are still issues here)
Submitted by: Ian Dowse <iedowse@maths.tcd.ie>
2002-07-18 21:19:56 +00:00
Julian Elischer
e602ba25fd Part 1 of KSE-III
The ability to schedule multiple threads per process
(one one cpu) by making ALL system calls optionally asynchronous.
to come: ia64 and power-pc patches, patches for gdb, test program (in tools)

Reviewed by:	Almost everyone who counts
	(at various times, peter, jhb, matt, alfred, mini, bernd,
	and a cast of thousands)

	NOTE: this is still Beta code, and contains lots of debugging stuff.
	expect slight instability in signals..
2002-06-29 17:26:22 +00:00
Ian Dowse
99568bcaf7 Display the mutex name in the ^T status line if the selected thread
is blocked on a mutex. Prepend a '*' to distinguish this case as
is done in top(1).
2002-06-20 14:03:36 +00:00
Dag-Erling Smørgrav
7aa57dca57 Nit: kern.ttys is of type S,xtty, not S,tty. 2002-05-31 16:11:49 +00:00
Dag-Erling Smørgrav
6b658142fd Add some checks to prevent NULL dereferences.
Submitted by:	jhay
2002-05-28 14:29:56 +00:00
Dag-Erling Smørgrav
6c533ac713 Add NAI copyright. 2002-05-28 06:53:41 +00:00
Dag-Erling Smørgrav
1a149fcd67 Introduce struct xtty, used when exporting tty information to userland.
Make kern.ttys export a struct xtty rather than struct tty.  Since struct
tty is no longer exposed to userland, remove the dev_t / udev_t hack.

Sponsored by:	DARPA, NAI Labs
2002-05-28 05:40:53 +00:00
Dag-Erling Smørgrav
4b4c18f861 ANSIfy (significant portions were already partly ANSIfied) 2002-05-25 15:52:53 +00:00
Dag-Erling Smørgrav
b7457aabf6 Remove register. 2002-05-25 15:44:38 +00:00
Dag-Erling Smørgrav
dedf14f521 Automated whitespace cleanup. 2002-05-25 15:43:06 +00:00
Alfred Perlstein
e649887b1e Make funsetown() take a 'struct sigio **' so that the locking can
be done internally.

Ensure that no one can fsetown() to a dying process/pgrp.  We need
to check the process for P_WEXIT to see if it's exiting.  Process
groups are already safe because there is no such thing as a pgrp
zombie, therefore the proctree lock completely protects the pgrp
from having sigio structures associated with it after it runs
funsetownlst.

Add sigio lock to witness list under proctree and allproc, but over
proc and pgrp.

Seigo Tanimura helped with this.
2002-05-06 19:31:28 +00:00
Alfred Perlstein
f132072368 Redo the sigio locking.
Turn the sigio sx into a mutex.

Sigio lock is really only needed to protect interrupts from dereferencing
the sigio pointer in an object when the sigio itself is being destroyed.

In order to do this in the most unintrusive manner change pgsigio's
sigio * argument into a **, that way we can lock internally to the
function.
2002-05-01 20:44:46 +00:00
John Baldwin
596325f154 - Lock proctree_lock instead of pgrpsess_lock.
- Use temporary variables to hold a pointer to a pgrp while we dink with it
  while not holding either the associated proc lock or proctree_lock.  It
  is in theory possible that p->p_pgrp could change out from under us.
2002-04-16 17:09:22 +00:00
Ruslan Ermilov
12c79eb288 Dike out a highly insecure UCONSOLE option.
TIOCCONS must be able to VOP_ACCESS() /dev/console to succeed.

Obtained from:	OpenBSD
2002-04-03 10:56:59 +00:00
Seigo Tanimura
2a60b9b951 Fix leakage of p_pgrp lock. 2002-04-02 17:12:06 +00:00
John Baldwin
44731cab3b Change the suser() API to take advantage of td_ucred as well as do a
general cleanup of the API.  The entire API now consists of two functions
similar to the pre-KSE API.  The suser() function takes a thread pointer
as its only argument.  The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0.  The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.

Discussed on:	smp@
2002-04-01 21:31:13 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
Alfred Perlstein
85f190e4d1 Fixes to make select/poll mpsafe.
Problem:
  selwakeup required calling pfind which would cause lock order
  reversals with the allproc_lock and the per-process filedesc lock.
Solution:
  Instead of recording the pid of the select()'ing process into the
  selinfo structure, actually record a pointer to the thread.  To
  avoid dereferencing a bad address all the selinfo structures that
  are in use by a thread are kept in a list hung off the thread
  (protected by sellock).  When a selwakeup occurs the selinfo is
  removed from that threads list, it is also removed on the way out
  of select or poll where the thread will traverse its list removing
  all the selinfos from its own list.

Problem:
  Previously the PROC_LOCK was used to provide the mutual exclusion
  needed to ensure proper locking, this couldn't work because there
  was a single condvar used for select and poll and condvars can
  only be used with a single mutex.
Solution:
  Introduce a global mutex 'sellock' which is used to provide mutual
  exclusion when recording events to wait on as well as performing
  notification when an event occurs.

Interesting note:
  schedlock is required to manipulate the per-thread TDF_SELECT
  flag, however if given its own field it would not need schedlock,
  also because TDF_SELECT is only manipulated under sellock one
  doesn't actually use schedlock for syncronization, only to protect
  against corruption.

Proc locks are no longer used in select/poll.

Portions contributed by: davidc
2002-03-14 01:32:30 +00:00
Seigo Tanimura
183ccde6c6 Stop abusing the pgrpsess_lock. 2002-03-11 07:53:13 +00:00
Seigo Tanimura
92c914f936 Fix lock leakage and late unlock.
Submitted by:	bde
2002-03-02 12:42:24 +00:00
Poul-Henning Kamp
e9be968e95 Fix a typo (?) in previous commit told ttyprintf() to print the integer
part of the user-time as a 64bit quantity.  This resulted in weird
output from SIGINFO.
2002-02-24 19:56:41 +00:00
Seigo Tanimura
f591779bb5 Lock struct pgrp, session and sigio.
New locks are:

- pgrpsess_lock which locks the whole pgrps and sessions,
- pg_mtx which protects the pgrp members, and
- s_mtx which protects the session members.

Please refer to sys/proc.h for the coverage of these locks.

Changes on the pgrp/session interface:

- pgfind() needs the pgrpsess_lock held.

- The caller of enterpgrp() is responsible to allocate a new pgrp and
  session.

- Call enterthispgrp() in order to enter an existing pgrp.

- pgsignal() requires a pgrp lock held.

Reviewed by:	jhb, alfred
Tested on:	cvsup.jp.FreeBSD.org
		(which is a quad-CPU machine running -current)
2002-02-23 11:12:57 +00:00
Peter Wemm
2b8a08af6b Fix a couple of style bugs introduced (or touched by) previous commit. 2002-02-07 23:06:26 +00:00
Julian Elischer
079b7badea Pre-KSE/M3 commit.
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.

Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
2002-02-07 20:58:47 +00:00
Peter Wemm
857ff6155b utime/stime.tv_sec are elapsed times, not relative to 1970. We can
safely print them as longs.  Even if ^T overflows after a process
has accumulated 68 years of user or system time, it is no big deal.
2001-11-17 00:26:57 +00:00
Peter Wemm
aa89942676 You cannot cast a time_t to quad_t and printf it with %lld. quad_t is
64 bits, not long long.
2001-11-16 23:53:48 +00:00
Robert Watson
fc5d29ef7d o Move suser() calls in kern/ to using suser_xxx() with an explicit
credential selection, rather than reference via a thread or process
  pointer.  This is part of a gradual migration to suser() accepting
  a struct ucred instead of a struct proc, simplifying the reference
  and locking semantics of suser().

Obtained from:	TrustedBSD Project
2001-11-01 20:56:57 +00:00
Matthew Dillon
434d21ccbf Make ttyprintf() of tv_sec value type agnostic. 2001-10-29 01:23:28 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00
Peter Wemm
b03a0c9e5e Fix a warning on alpha (real problem) and make pstat -t work as a bonus.
'struct tty' was out of sync in user and kernel due to dev_t/udev_t
mixups.  This takes advantage of the fact that dev_t changes type in
userland, so it isn't too pretty.
2001-09-10 12:05:47 +00:00
Thomas Moestl
12543b2e98 Export the tk_nin and tk_nout variables (number of tty input/output
characters) as sysctls (kern.tty_nin and kern.tty_nout).
2001-08-04 18:09:24 +00:00
Dima Dorfman
0150c6e83d Unifdef DEV_SNP; snp(4) no longer requires these ugly hacks.
Silence by:	-hackers, -audit
2001-05-22 22:16:18 +00:00
Mark Murray
fb919e4d5a Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
other "system" header files.

Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.

Sort sys/*.h includes where possible in affected files.

OK'ed by:	bde (with reservations)
2001-05-01 08:13:21 +00:00
John Baldwin
19eb87d22a Grab the process lock while calling psignal and before calling psignal. 2001-03-07 03:37:06 +00:00
Assar Westerlund
3617ddfc33 implement OCRNL, ONOCR, and ONLRET
Obtained from:	NetBSD
2001-03-04 06:04:50 +00:00
Jonathan Lemon
9bfd6482c8 Fix tab breakage from last commit.
Spotted by: bde
2001-02-17 19:40:22 +00:00
Jonathan Lemon
608a3ce62a Extend kqueue down to the device layer.
Backwards compatible approach suggested by: peter
2001-02-15 16:34:11 +00:00
Bosko Milekic
9ed346bab0 Change and clean the mutex lock interface.
mtx_enter(lock, type) becomes:

mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)

similarily, for releasing a lock, we now have:

mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.

The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.

Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:

MTX_QUIET and MTX_NOSWITCH

The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:

mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.

Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.

Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.

Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.

Finally, caught up to the interface changes in all sys code.

Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
Peter Wemm
810d0bd1a9 Turn '#if NSNP > 0' into an option. 2001-01-29 09:43:36 +00:00
John Baldwin
168666be74 - Catch up to proc flag changes.
- Assert sched_lock is held in proc_compare.
2001-01-24 11:15:59 +00:00
John Baldwin
27e864e300 - All of proc_compare needs sched_lock, so hold it for the for loop that
calls it rather than obtaining and releasing it a lot in proc_compare.
- Collect all of the data gathering and stick it just after the
  proc_compare loop.  This way, we only have to grab sched_lock once now
  when handling SIGINFO.  All the printf's are done after the values are
  calculated.

Submitted mostly by:	bde
2001-01-20 23:03:20 +00:00
John Baldwin
4848fbae35 Be more careful with sched_lock in the SIGINFO handler. Specifically, do
not hold sched_lock while calling ttyprintf().  If we are on a serial
console, then ttyprintf() will end up getting the sio lock, resulting in
a lock order violation.

Noticed by:	des
2001-01-20 02:04:44 +00:00
David Malone
7cc0979fd6 Convert more malloc+bzero to malloc+M_ZERO.
Submitted by:	josh@zipperup.org
Submitted by:	Robert Drehmel <robd@gmx.net>
2000-12-08 21:51:06 +00:00
John Baldwin
0ebabc93a4 Protect p_stat with sched_lock. 2000-12-02 01:32:51 +00:00
Jordan K. Hubbard
7022a92395 Kernel support for erase2 character.
Submitted by:	Rui Pedro Mendes Salgueiro <rps@mat.uc.pt>
2000-11-28 20:03:23 +00:00