Commit Graph

22 Commits

Author SHA1 Message Date
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
Greg Lehey
940b9a4808 struct rangelock: Remove the field 'plex' from the entry. Range locks
are accessed only via the plex, so there's never any confusion as to
the plex number.  This value was, as a result, unused.
2001-01-14 06:34:57 +00:00
Greg Lehey
83d4664f33 Remove obsolete functions [un]lockplex and [un]lockvol.
Rewrite lockrange and unlockrange.  The lock table is now a fixed
size, so there is no possibility for race conditions when expanding.
The current size (256 locked ranges) should be large enough that it
makes no sense to expand it.  To do expansion right would require
quiescing the plex (requiring at least 256 I/O completions), and the
performance implications are horrendous.

Add a mutex per plex for accessing the lock table.

Based on analysis by:	tegge
2001-01-10 05:06:37 +00:00
Greg Lehey
9702452a12 lockrange: Avoid a race condition which was causing random corruption,
panics and hangs in RAID-5 plexes, particularly with ata drives.

Original-code-by:   Bernd Walter <ticso@cicely.de>
Eagerly-awaited-by: sos
2000-05-04 07:37:11 +00:00
Greg Lehey
b51b6b8a7b Don't tsleep with PCATCH, it's a wonderful way to hang the system.
Reported-by:	Bernd Walter <ticso@cicely.de>
2000-01-05 22:59:36 +00:00
Greg Lehey
667b5ca097 Don't count iterations while waiting for a lock to become free. 1999-09-28 22:56:04 +00:00
Greg Lehey
1fa2fb7bf2 Reverse MFC of revision 1.5.2.7:
Remove a rather embarrassing race condition.

Egged-on-by:	alfred
1999-09-03 01:37:26 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Greg Lehey
ca55837990 config_plex: don't allocate a rangelock struct.
lockrange: correctly expand rangelock struct, including expanding a
	   null struct.  Previously lockrange would attempt to lock a
	   NULL pointer under these circumstances.

Reported-by:	Ian Freislich <iang@uunet.co.za>
1999-08-26 03:25:38 +00:00
Greg Lehey
c4bbdf0e5a Change parameters of unlockrange to allow calling from revive_block,
which doesn't use request groups.
1999-08-24 02:23:21 +00:00
Greg Lehey
998115ba43 rewrite lockrange and unlockrange. Hopefully the current version will
solve some data integrity problems that have been reported with
degraded RAID-5 plexes.

Reported-by:	Bernd Walter <ticso@cicely.de>
		Remy Nonnenmacher <remy@synx.com>
1999-08-14 06:28:21 +00:00
Greg Lehey
b853969e09 Import RAID-5 code.
Add Cybernet copyright.

OK'd-by:     Chuck Jacobus <chuck@cybernet.com>
1999-08-07 08:11:22 +00:00
Greg Lehey
e4d6d0216b Modify to work with new style dev_t.
With_copious_input_from:  peter
			  phk
1999-05-15 05:49:21 +00:00
Greg Lehey
560863926b Remove old grunge, including references to sys/disk.h (which is going
away).

Submitted-by:	phk
1999-05-07 01:35:29 +00:00
Greg Lehey
7ffb59f668 lockdrive: Add debug calls to catch occasional deadlocks on drives.
The problem is probably gone, but the debug checks remain
	   for a while.
1999-04-10 08:11:21 +00:00
Greg Lehey
5c6d2cb543 lock_drive: report on and recover from an obscure situation where the
daemon can deadlock against itself.
1999-03-13 07:35:40 +00:00
Greg Lehey
7f1050341c Change multiline comments to start with a lone /* and end with a */,
apparently in accordance with style(9).

Complained-about-by: bde
1999-01-29 01:17:54 +00:00
Greg Lehey
ba40e00009 Create functions lockdrive and unlockdrive to handle drive locking 1999-01-21 00:37:38 +00:00
Peter Wemm
c285ca1254 Some relatively minor tweaks to enable vinum to be built into a static
kernel as a pseudo-device.  The changes were:
- #ifdef DEBUG -> #ifdef VINUMDEBUG
- opt_vinum.h for holding above config variable
- Fixing up a few stray problems where DEBUG wasn't optional.
- config.c -> vinumconfig.c (there's already a config.o)
- Other *.c -> vinum*.c (wasn't strictly necessary, but done in case we end
  up with something else conflicting later on and we might have to have yet
  more repository copies of files).
- include file paths fixups..  (ie: get them all from the kernel tree
  instead of partly from the kernel and partly from /usr/include/machine)

I've spoken with Greg about this..  I hope this doesn't mess him around
too much..
1998-12-28 16:28:24 +00:00
Peter Wemm
ef2dbe9885 If I've done this right, revive the vinum code in it's now home after it
was savaged in the blood bath a few hours ago.
1998-12-28 04:56:24 +00:00
Søren Schmidt
c74cd3590f Remove LKM's depricated by modules. 1998-12-27 19:38:15 +00:00
Greg Lehey
e4381fa521 Import base vinum lkm sources 1998-09-16 05:56:21 +00:00