diff --git a/sys/kern/kern_lock.c b/sys/kern/kern_lock.c index 28eeb42ad14..11396a6e259 100644 --- a/sys/kern/kern_lock.c +++ b/sys/kern/kern_lock.c @@ -736,6 +736,7 @@ lockmgr_xlock_hard(struct lock *lk, u_int flags, struct lock_object *ilk, panic("%s: recursing on non recursive lockmgr %p " "@ %s:%d\n", __func__, lk, file, line); } + atomic_set_ptr(&lk->lk_lock, LK_WRITER_RECURSED); lk->lk_recurse++; LOCK_LOG2(lk, "%s: %p recursing", __func__, lk); LOCK_LOG_LOCK("XLOCK", &lk->lock_object, 0, @@ -1039,9 +1040,11 @@ lockmgr_xunlock_hard(struct lock *lk, uintptr_t x, u_int flags, struct lock_obje * The lock is held in exclusive mode. * If the lock is recursed also, then unrecurse it. */ - if (lockmgr_xlocked_v(x) && lockmgr_recursed(lk)) { + if (lockmgr_recursed_v(x)) { LOCK_LOG2(lk, "%s: %p unrecursing", __func__, lk); lk->lk_recurse--; + if (lk->lk_recurse == 0) + atomic_clear_ptr(&lk->lk_lock, LK_WRITER_RECURSED); goto out; } if (tid != LK_KERNPROC) @@ -1187,9 +1190,8 @@ lockmgr_unlock(struct lock *lk) } else { tid = (uintptr_t)curthread; lockmgr_note_exclusive_release(lk, file, line); - if (!lockmgr_recursed(lk) && - atomic_cmpset_rel_ptr(&lk->lk_lock, tid, LK_UNLOCKED)) { - LOCKSTAT_PROFILE_RELEASE_RWLOCK(lockmgr__release, lk, LOCKSTAT_WRITER); + if (x == tid && atomic_cmpset_rel_ptr(&lk->lk_lock, tid, LK_UNLOCKED)) { + LOCKSTAT_PROFILE_RELEASE_RWLOCK(lockmgr__release, lk,LOCKSTAT_WRITER); } else { return (lockmgr_xunlock_hard(lk, x, LK_RELEASE, NULL, file, line)); } diff --git a/sys/sys/lockmgr.h b/sys/sys/lockmgr.h index 65a06d7f3ec..336f5700701 100644 --- a/sys/sys/lockmgr.h +++ b/sys/sys/lockmgr.h @@ -42,13 +42,14 @@ #define LK_SHARED_WAITERS 0x02 #define LK_EXCLUSIVE_WAITERS 0x04 #define LK_EXCLUSIVE_SPINNERS 0x08 +#define LK_WRITER_RECURSED 0x10 #define LK_ALL_WAITERS \ (LK_SHARED_WAITERS | LK_EXCLUSIVE_WAITERS) #define LK_FLAGMASK \ - (LK_SHARE | LK_ALL_WAITERS | LK_EXCLUSIVE_SPINNERS) + (LK_SHARE | LK_ALL_WAITERS | LK_EXCLUSIVE_SPINNERS | LK_WRITER_RECURSED) #define LK_HOLDER(x) ((x) & ~LK_FLAGMASK) -#define LK_SHARERS_SHIFT 4 +#define LK_SHARERS_SHIFT 5 #define LK_SHARERS(x) (LK_HOLDER(x) >> LK_SHARERS_SHIFT) #define LK_SHARERS_LOCK(x) ((x) << LK_SHARERS_SHIFT | LK_SHARE) #define LK_ONE_SHARER (1 << LK_SHARERS_SHIFT) @@ -131,8 +132,10 @@ _lockmgr_args_rw(struct lock *lk, u_int flags, struct rwlock *ilk, LOCK_FILE, LOCK_LINE) #define lockmgr_disown(lk) \ _lockmgr_disown((lk), LOCK_FILE, LOCK_LINE) +#define lockmgr_recursed_v(v) \ + (v & LK_WRITER_RECURSED) #define lockmgr_recursed(lk) \ - ((lk)->lk_recurse != 0) + lockmgr_recursed_v((lk)->lk_lock) #define lockmgr_rw(lk, flags, ilk) \ _lockmgr_args_rw((lk), (flags), (ilk), LK_WMESG_DEFAULT, \ LK_PRIO_DEFAULT, LK_TIMO_DEFAULT, LOCK_FILE, LOCK_LINE)