diff options
| author |   Will Deacon <will.deacon@arm.com> | 2017-10-03 19:25:27 +0100 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2017-10-10 11:50:18 +0200 |
| commit | a8a217c22116eff6c120d753c9934089fb229af0 (patch) | |
| tree | d56f1283ba7153f9ead9fb92c1a1794143c6e4a3 /include/asm-generic/qrwlock.h | |
| parent | locking/rwsem, security/apparmor: Replace homebrew use of write_can_lock() with lockdep (diff) | |
| download | wireguard-linux-a8a217c22116eff6c120d753c9934089fb229af0.tar.xz wireguard-linux-a8a217c22116eff6c120d753c9934089fb229af0.zip | |
locking/core: Remove {read,spin,write}_can_lock()
Outside of the locking code itself, {read,spin,write}_can_lock() have no
users in tree. Apparmor (the last remaining user of write_can_lock()) got
moved over to lockdep by the previous patch.
This patch removes the use of {read,spin,write}_can_lock() from the
BUILD_LOCK_OPS macro, deferring to the trylock operation for testing the
lock status, and subsequently removes the unused macros altogether. They
aren't guaranteed to work in a concurrent environment and can give
incorrect results in the case of qrwlock.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1507055129-12300-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/asm-generic/qrwlock.h')
| -rw-r--r-- | include/asm-generic/qrwlock.h | 20 |
1 files changed, 0 insertions, 20 deletions
diff --git a/include/asm-generic/qrwlock.h b/include/asm-generic/qrwlock.h index 7d026bf27713..50925327b0a8 100644 --- a/include/asm-generic/qrwlock.h +++ b/include/asm-generic/qrwlock.h @@ -53,24 +53,6 @@ extern void queued_read_lock_slowpath(struct qrwlock *lock, u32 cnts); extern void queued_write_lock_slowpath(struct qrwlock *lock); /** - * queued_read_can_lock- would read_trylock() succeed? - * @lock: Pointer to queue rwlock structure - */ -static inline int queued_read_can_lock(struct qrwlock *lock) -{ - return !(atomic_read(&lock->cnts) & _QW_WMASK); -} - -/** - * queued_write_can_lock- would write_trylock() succeed? - * @lock: Pointer to queue rwlock structure - */ -static inline int queued_write_can_lock(struct qrwlock *lock) -{ - return !atomic_read(&lock->cnts); -} - -/** * queued_read_trylock - try to acquire read lock of a queue rwlock * @lock : Pointer to queue rwlock structure * Return: 1 if lock acquired, 0 if failed @@ -169,8 +151,6 @@ static inline void queued_write_unlock(struct qrwlock *lock) * Remapping rwlock architecture specific functions to the corresponding * queue rwlock functions. */ -#define arch_read_can_lock(l) queued_read_can_lock(l) -#define arch_write_can_lock(l) queued_write_can_lock(l) #define arch_read_lock(l) queued_read_lock(l) #define arch_write_lock(l) queued_write_lock(l) #define arch_read_trylock(l) queued_read_trylock(l) |