diff options
| author | Ingo Molnar <mingo@elte.hu> | 2006-02-07 12:58:54 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-02-07 16:12:33 -0800 |
| commit | e0a602963485a2f109ae1521c0c55507304c63ed (patch) | |
| tree | 38900590f1d4f129cfd8748949ff62f7d3296aee /lib/spinlock_debug.c | |
| parent | 8519fb30e438f8088b71a94a7d5a660a814d3872 (diff) | |
| download | lwn-e0a602963485a2f109ae1521c0c55507304c63ed.tar.gz lwn-e0a602963485a2f109ae1521c0c55507304c63ed.zip | |
[PATCH] Fix spinlock debugging delays to not time out too early
The spinlock-debug wait-loop was using loops_per_jiffy to detect too long
spinlock waits - but on fast CPUs this led to a way too fast timeout and false
messages.
The fix is to include a __delay(1) call in the loop, to correctly approximate
the intended delay timeout of 1 second. The code assumes that every
architecture implements __delay(1) to last around 1/(loops_per_jiffy*HZ)
seconds.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'lib/spinlock_debug.c')
| -rw-r--r-- | lib/spinlock_debug.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c index c8bb8cc899d7..d8b6bb419d49 100644 --- a/lib/spinlock_debug.c +++ b/lib/spinlock_debug.c @@ -72,9 +72,9 @@ static void __spin_lock_debug(spinlock_t *lock) for (;;) { for (i = 0; i < loops_per_jiffy * HZ; i++) { - cpu_relax(); if (__raw_spin_trylock(&lock->raw_lock)) return; + __delay(1); } /* lockup suspected: */ if (print_once) { @@ -144,9 +144,9 @@ static void __read_lock_debug(rwlock_t *lock) for (;;) { for (i = 0; i < loops_per_jiffy * HZ; i++) { - cpu_relax(); if (__raw_read_trylock(&lock->raw_lock)) return; + __delay(1); } /* lockup suspected: */ if (print_once) { @@ -217,9 +217,9 @@ static void __write_lock_debug(rwlock_t *lock) for (;;) { for (i = 0; i < loops_per_jiffy * HZ; i++) { - cpu_relax(); if (__raw_write_trylock(&lock->raw_lock)) return; + __delay(1); } /* lockup suspected: */ if (print_once) { |