GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

locking/rwsem: Make rwsem->owner an atomic_long_t

Browse source 
The rwsem->owner contains not just the task structure pointer, it also
holds some flags for storing the current state of the rwsem. Some of
the flags may have to be atomically updated. To reflect the new reality,
the owner is now changed to an atomic_long_t type.

New helper functions are added to properly separate out the task
structure pointer and the embedded flags.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: huang ying <huang.ying.caritas@gmail.com>
Link: https://lkml.kernel.org/r/20190520205918.22251-14-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Waiman Long 2019-05-20 16:59:12 -04:00 • committed by Ingo Molnar
parent cf69482d62
commit 94a9717b3c
3 changed files with 88 additions and 52 deletions
Download patch file Download diff file Expand all files Collapse all files

4
include/linux/percpu-rwsem.h
View file

@ -117,7 +117,7 @@ static inline void percpu_rwsem_release(struct percpu_rw_semaphore *sem,
lock_release(&sem->rw_sem.dep_map, 1, ip);
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
if (!read)
sem->rw_sem.owner = RWSEM_OWNER_UNKNOWN;
atomic_long_set(&sem->rw_sem.owner, RWSEM_OWNER_UNKNOWN);
#endif
}
@ -127,7 +127,7 @@ static inline void percpu_rwsem_acquire(struct percpu_rw_semaphore *sem,
lock_acquire(&sem->rw_sem.dep_map, 0, 1, read, 1, NULL, ip);
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
if (!read)
sem->rw_sem.owner = current;
atomic_long_set(&sem->rw_sem.owner, (long)current);
#endif
}