From f607c6685774811b8112e124f10a053d77015485 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 20 Jul 2009 19:16:29 +0200 Subject: lockdep: Introduce lockdep_assert_held() Add a lockdep helper to validate that we indeed are the owner of a lock. Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 33 +++++++++++++++++++++++++++++++++ kernel/sched.c | 2 ++ 2 files changed, 35 insertions(+) (limited to 'kernel') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 4b6cebe8ab3..28914a50991 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -3059,6 +3059,19 @@ __lock_release(struct lockdep_map *lock, int nested, unsigned long ip) check_chain_key(curr); } +static int __lock_is_held(struct lockdep_map *lock) +{ + struct task_struct *curr = current; + int i; + + for (i = 0; i < curr->lockdep_depth; i++) { + if (curr->held_locks[i].instance == lock) + return 1; + } + + return 0; +} + /* * Check whether we follow the irq-flags state precisely: */ @@ -3160,6 +3173,26 @@ void lock_release(struct lockdep_map *lock, int nested, } EXPORT_SYMBOL_GPL(lock_release); +int lock_is_held(struct lockdep_map *lock) +{ + unsigned long flags; + int ret = 0; + + if (unlikely(current->lockdep_recursion)) + return ret; + + raw_local_irq_save(flags); + check_flags(flags); + + current->lockdep_recursion = 1; + ret = __lock_is_held(lock); + current->lockdep_recursion = 0; + raw_local_irq_restore(flags); + + return ret; +} +EXPORT_SYMBOL_GPL(lock_is_held); + void lockdep_set_current_reclaim_state(gfp_t gfp_mask) { current->lockdep_reclaim_gfp = gfp_mask; diff --git a/kernel/sched.c b/kernel/sched.c index 1b59e265273..2c75f7daa43 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6609,6 +6609,8 @@ int cond_resched_lock(spinlock_t *lock) int resched = should_resched(); int ret = 0; + lockdep_assert_held(lock); + if (spin_needbreak(lock) || resched) { spin_unlock(lock); if (resched) -- cgit v1.2.3