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 /arch/metag | |
| parent | 26c4eb192c6224e5297496cead36404b62fb071b (diff) | |
| download | linux-a8a217c22116eff6c120d753c9934089fb229af0.tar.bz2 | |
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 'arch/metag')
| -rw-r--r-- | arch/metag/include/asm/spinlock_lnkget.h | 30 | ||||
| -rw-r--r-- | arch/metag/include/asm/spinlock_lock1.h | 20 |
2 files changed, 0 insertions, 50 deletions
diff --git a/arch/metag/include/asm/spinlock_lnkget.h b/arch/metag/include/asm/spinlock_lnkget.h index ad8436feed8d..6a932a952d53 100644 --- a/arch/metag/include/asm/spinlock_lnkget.h +++ b/arch/metag/include/asm/spinlock_lnkget.h @@ -136,21 +136,6 @@ static inline void arch_write_unlock(arch_rwlock_t *rw) : "memory"); } -/* write_can_lock - would write_trylock() succeed? */ -static inline int arch_write_can_lock(arch_rwlock_t *rw) -{ - int ret; - - asm volatile ("LNKGETD %0, [%1]\n" - "CMP %0, #0\n" - "MOV %0, #1\n" - "XORNZ %0, %0, %0\n" - : "=&d" (ret) - : "da" (&rw->lock) - : "cc"); - return ret; -} - /* * Read locks are a bit more hairy: * - Exclusively load the lock value. @@ -224,21 +209,6 @@ static inline int arch_read_trylock(arch_rwlock_t *rw) return tmp; } -/* read_can_lock - would read_trylock() succeed? */ -static inline int arch_read_can_lock(arch_rwlock_t *rw) -{ - int tmp; - - asm volatile ("LNKGETD %0, [%1]\n" - "CMP %0, %2\n" - "MOV %0, #1\n" - "XORZ %0, %0, %0\n" - : "=&d" (tmp) - : "da" (&rw->lock), "bd" (0x80000000) - : "cc"); - return tmp; -} - #define arch_read_lock_flags(lock, flags) arch_read_lock(lock) #define arch_write_lock_flags(lock, flags) arch_write_lock(lock) diff --git a/arch/metag/include/asm/spinlock_lock1.h b/arch/metag/include/asm/spinlock_lock1.h index c630444cffe9..8ae12bfc8ad8 100644 --- a/arch/metag/include/asm/spinlock_lock1.h +++ b/arch/metag/include/asm/spinlock_lock1.h @@ -104,16 +104,6 @@ static inline void arch_write_unlock(arch_rwlock_t *rw) rw->lock = 0; } -/* write_can_lock - would write_trylock() succeed? */ -static inline int arch_write_can_lock(arch_rwlock_t *rw) -{ - unsigned int ret; - - barrier(); - ret = rw->lock; - return (ret == 0); -} - /* * Read locks are a bit more hairy: * - Exclusively load the lock value. @@ -171,14 +161,4 @@ static inline int arch_read_trylock(arch_rwlock_t *rw) return (ret < 0x80000000); } -/* read_can_lock - would read_trylock() succeed? */ -static inline int arch_read_can_lock(arch_rwlock_t *rw) -{ - unsigned int ret; - - barrier(); - ret = rw->lock; - return (ret < 0x80000000); -} - #endif /* __ASM_SPINLOCK_LOCK1_H */ |