From d0aa7a70bf03b9de9e995ab272293be1f7937822 Mon Sep 17 00:00:00 2001 From: Pierre Peiffer Date: Wed, 9 May 2007 02:35:02 -0700 Subject: 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 Cc: Ingo Molnar Cc: Ulrich Drepper Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/futex.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include/linux/futex.h') 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 @@ -84,10 +85,15 @@ 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; -- cgit v1.2.3-59-g8ed1b