From: Andrew Morton Date: Sat, 5 Aug 2006 19:13:47 +0000 (-0700) Subject: disable debugging version of write_lock() X-Git-Tag: v2.6.17.11~14 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a80b26d5597e62094c165c26e77fde4d4ab2e37e;p=thirdparty%2Fkernel%2Fstable.git disable debugging version of write_lock() We've confirmed that the debug version of write_lock() can get stuck for long enough to cause NMI watchdog timeouts and hence a crash. We don't know why, yet. Disable it for now. Also disable the similar read_lock() code. Just in case. Thanks to Dave Olson for reporting and testing. Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c index d8b6bb419d49c..5cbcb806b0827 100644 --- a/lib/spinlock_debug.c +++ b/lib/spinlock_debug.c @@ -137,6 +137,7 @@ static void rwlock_bug(rwlock_t *lock, const char *msg) #define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg) +#if 0 /* __write_lock_debug() can lock up - maybe this can too? */ static void __read_lock_debug(rwlock_t *lock) { int print_once = 1; @@ -159,12 +160,12 @@ static void __read_lock_debug(rwlock_t *lock) } } } +#endif void _raw_read_lock(rwlock_t *lock) { RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic"); - if (unlikely(!__raw_read_trylock(&lock->raw_lock))) - __read_lock_debug(lock); + __raw_read_lock(&lock->raw_lock); } int _raw_read_trylock(rwlock_t *lock) @@ -210,6 +211,7 @@ static inline void debug_write_unlock(rwlock_t *lock) lock->owner_cpu = -1; } +#if 0 /* This can cause lockups */ static void __write_lock_debug(rwlock_t *lock) { int print_once = 1; @@ -232,12 +234,12 @@ static void __write_lock_debug(rwlock_t *lock) } } } +#endif void _raw_write_lock(rwlock_t *lock) { debug_write_lock_before(lock); - if (unlikely(!__raw_write_trylock(&lock->raw_lock))) - __write_lock_debug(lock); + __raw_write_lock(&lock->raw_lock); debug_write_lock_after(lock); }