Messages in this thread Patch in this message | | | From | Michal Hocko <> | Subject | [RFC 11/12] x86, rwsem: provide __down_write_killable | Date | Tue, 2 Feb 2016 21:19:28 +0100 |
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From: Michal Hocko <mhocko@suse.com>
which is uses the same fast path as __down_write except it falls back to rwsem_down_write_failed_killable slow path and return -EINTR if killed.
Signed-off-by: Michal Hocko <mhocko@suse.com> --- arch/x86/include/asm/rwsem.h | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h index 1b5e89b3643d..64899daa51e2 100644 --- a/arch/x86/include/asm/rwsem.h +++ b/arch/x86/include/asm/rwsem.h @@ -109,6 +109,19 @@ static inline void __down_write(struct rw_semaphore *sem) rwsem_down_write_failed(sem); } +static inline int __down_write_killable(struct rw_semaphore *sem) +{ + long tmp; + + tmp = atomic_long_add_return(RWSEM_ACTIVE_WRITE_BIAS, + (atomic_long_t *)&sem->count); + if (unlikely(tmp != RWSEM_ACTIVE_WRITE_BIAS)) + if (IS_ERR(rwsem_down_write_failed_killable(sem))) + return -EINTR; + + return 0; +} + /* * trylock for writing -- returns 1 if successful, 0 if contention */ -- 2.7.0
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