diff options
| author | Pierre Peiffer <pierre.peiffer@bull.net> | 2007-05-09 11:35:02 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-09 21:30:55 +0200 |
| commit | d0aa7a70bf03b9de9e995ab272293be1f7937822 (patch) | |
| tree | 194b30b7b8374b946f166996cb99fb95eb3b7819 /include | |
| parent | Make futex_wait() use an hrtimer for timeout (diff) | |
| download | linux-d0aa7a70bf03b9de9e995ab272293be1f7937822.tar.xz linux-d0aa7a70bf03b9de9e995ab272293be1f7937822.zip | |
futex_requeue_pi optimization
This patch provides the futex_requeue_pi functionality, which allows some
threads waiting on a normal futex to be requeued on the wait-queue of a
PI-futex.
This provides an optimization, already used for (normal) futexes, to be used
with the PI-futexes.
This optimization is currently used by the glibc in pthread_broadcast, when
using "normal" mutexes. With futex_requeue_pi, it can be used with
PRIO_INHERIT mutexes too.
Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/futex.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/include/linux/futex.h b/include/linux/futex.h index 34e54f2b8997..1bd8dfcb037b 100644 --- a/include/linux/futex.h +++ b/include/linux/futex.h @@ -17,6 +17,7 @@ union ktime; #define FUTEX_LOCK_PI 6 #define FUTEX_UNLOCK_PI 7 #define FUTEX_TRYLOCK_PI 8 +#define FUTEX_CMP_REQUEUE_PI 9 /* * Support for robust futexes: the kernel cleans up held futexes at @@ -85,9 +86,14 @@ struct robust_list_head { #define FUTEX_OWNER_DIED 0x40000000 /* + * Some processes have been requeued on this PI-futex + */ +#define FUTEX_WAITER_REQUEUED 0x20000000 + +/* * The rest of the robust-futex field is for the TID: */ -#define FUTEX_TID_MASK 0x3fffffff +#define FUTEX_TID_MASK 0x0fffffff /* * This limit protects against a deliberately circular list. @@ -111,6 +117,7 @@ handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi); * We set bit 0 to indicate if it's an inode-based key. */ union futex_key { + u32 __user *uaddr; struct { unsigned long pgoff; struct inode *inode; |