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| author | jhb <jhb@FreeBSD.org> | 2007-05-19 16:35:27 +0000 |
|---|---|---|
| committer | jhb <jhb@FreeBSD.org> | 2007-05-19 16:35:27 +0000 |
| commit | 410a2fc7eb4aca4e3114f237c2dea683ab1e404f (patch) | |
| tree | 24c4105607db611659cd8034f65b27a2706cd007 /sys/kern/kern_sx.c | |
| parent | 643c457209498033ae2cddd70831b39918d945f0 (diff) | |
| download | FreeBSD-src-410a2fc7eb4aca4e3114f237c2dea683ab1e404f.zip FreeBSD-src-410a2fc7eb4aca4e3114f237c2dea683ab1e404f.tar.gz | |
Add a new SX_RECURSE flag to make support for recursive exclusive locks
conditional. By default, sx(9) locks are back to not supporting recursive
exclusive locks.
Submitted by: attilio
Diffstat (limited to 'sys/kern/kern_sx.c')
| -rw-r--r-- | sys/kern/kern_sx.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/sys/kern/kern_sx.c b/sys/kern/kern_sx.c index 9ecba95..3a0973a 100644 --- a/sys/kern/kern_sx.c +++ b/sys/kern/kern_sx.c @@ -170,6 +170,9 @@ sx_init_flags(struct sx *sx, const char *description, int opts) { int flags; + MPASS((opts & ~(SX_QUIET | SX_RECURSE | SX_NOWITNESS | SX_DUPOK | + SX_NOPROFILE)) == 0); + flags = LO_SLEEPABLE | LO_UPGRADABLE | LO_RECURSABLE; if (opts & SX_DUPOK) flags |= LO_DUPOK; @@ -180,7 +183,7 @@ sx_init_flags(struct sx *sx, const char *description, int opts) if (opts & SX_QUIET) flags |= LO_QUIET; - flags |= opts & SX_ADAPTIVESPIN; + flags |= opts & (SX_ADAPTIVESPIN | SX_RECURSE); sx->sx_lock = SX_LOCK_UNLOCKED; sx->sx_recurse = 0; lock_init(&sx->lock_object, &lock_class_sx, description, NULL, flags); @@ -254,7 +257,7 @@ _sx_try_xlock(struct sx *sx, const char *file, int line) KASSERT(sx->sx_lock != SX_LOCK_DESTROYED, ("sx_try_xlock() of destroyed sx @ %s:%d", file, line)); - if (sx_xlocked(sx)) { + if (sx_xlocked(sx) && (sx->lock_object.lo_flags & SX_RECURSE) != 0) { sx->sx_recurse++; atomic_set_ptr(&sx->sx_lock, SX_LOCK_RECURSED); rval = 1; @@ -412,6 +415,9 @@ _sx_xlock_hard(struct sx *sx, uintptr_t tid, const char *file, int line) /* If we already hold an exclusive lock, then recurse. */ if (sx_xlocked(sx)) { + KASSERT((sx->lock_object.lo_flags & SX_RECURSE) != 0, + ("_sx_xlock_hard: recursed on non-recursive sx %s @ %s:%d\n", + sx->lock_object.lo_name, file, line)); sx->sx_recurse++; atomic_set_ptr(&sx->sx_lock, SX_LOCK_RECURSED); if (LOCK_LOG_TEST(&sx->lock_object, 0)) |
