From cd1a28e8457e6ebf72c48d84d4e736307e86436e Mon Sep 17 00:00:00 2001 From: "Huang, Ying" Date: Mon, 23 Jun 2008 11:20:54 +0800 Subject: lockdep: add lock_class information to lock_chain and output it It is based on x86/master branch of git-x86 tree, and has been tested on x86_64 platform. ChangeLog: v2: - Enclosing proc file system related code into CONFIG_PROVE_LOCKING. - Fix nr_chain_hlocks update code. Signed-off-by: Huang Ying Cc: Peter Zijlstra Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'kernel/lockdep.c') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index a796f1f38ac..7553a28b99c 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -1459,7 +1459,7 @@ out_bug: unsigned long nr_lock_chains; struct lock_chain lock_chains[MAX_LOCKDEP_CHAINS]; -atomic_t nr_chain_hlocks; +int nr_chain_hlocks; static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS]; struct lock_class *lock_chain_get_class(struct lock_chain *chain, int i) @@ -1481,7 +1481,7 @@ static inline int lookup_chain_cache(struct task_struct *curr, struct list_head *hash_head = chainhashentry(chain_key); struct lock_chain *chain; struct held_lock *hlock_curr, *hlock_next; - int i, j, n; + int i, j, n, cn; if (DEBUG_LOCKS_WARN_ON(!irqs_disabled())) return 0; @@ -1540,9 +1540,15 @@ cache_hit: } i++; chain->depth = curr->lockdep_depth + 1 - i; - n = atomic_add_return(chain->depth, &nr_chain_hlocks); - if (unlikely(n < MAX_LOCKDEP_CHAIN_HLOCKS)) { - chain->base = n - chain->depth; + cn = nr_chain_hlocks; + while (cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS) { + n = cmpxchg(&nr_chain_hlocks, cn, cn + chain->depth); + if (n == cn) + break; + cn = n; + } + if (likely(cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) { + chain->base = cn; for (j = 0; j < chain->depth - 1; j++, i++) { int lock_id = curr->held_locks[i].class - lock_classes; chain_hlocks[chain->base + j] = lock_id; -- cgit v1.2.3