From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Chen, Kenneth W" Date: Wed, 29 Mar 2006 01:06:25 +0000 Subject: Cleanup non-atomic bit operation Message-Id: <200603290105.k2T15ng00381@unix-os.sc.intel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Non-atomic version of __clear_bit uses volatile declaration, which turned into an expensive ordered operation. Fixed that up. Also fix up cosmetic function declaration for other non-atomic bit ops. Signed-off-by: Ken Chen --- ./include/asm-ia64/bitops.h.orig 2006-03-28 17:53:48.000000000 -0800 +++ ./include/asm-ia64/bitops.h 2006-03-28 17:57:45.000000000 -0800 @@ -57,7 +57,7 @@ set_bit (int nr, volatile void *addr) * may be that only one operation succeeds. */ static __inline__ void -__set_bit (int nr, volatile void *addr) +__set_bit (int nr, void *addr) { *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31)); } @@ -98,11 +98,9 @@ clear_bit (int nr, volatile void *addr) * __clear_bit - Clears a bit in memory (non-atomic version) */ static __inline__ void -__clear_bit (int nr, volatile void *addr) +__clear_bit (int nr, void *addr) { - volatile __u32 *p = (__u32 *) addr + (nr >> 5); - __u32 m = 1 << (nr & 31); - *p &= ~m; + *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31)); } /** @@ -140,7 +138,7 @@ change_bit (int nr, volatile void *addr) * may be that only one operation succeeds. */ static __inline__ void -__change_bit (int nr, volatile void *addr) +__change_bit (int nr, void *addr) { *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31)); } @@ -180,7 +178,7 @@ test_and_set_bit (int nr, volatile void * but actually fail. You must protect multiple accesses with a lock. */ static __inline__ int -__test_and_set_bit (int nr, volatile void *addr) +__test_and_set_bit (int nr, void *addr) { __u32 *p = (__u32 *) addr + (nr >> 5); __u32 m = 1 << (nr & 31); @@ -225,7 +223,7 @@ test_and_clear_bit (int nr, volatile voi * but actually fail. You must protect multiple accesses with a lock. */ static __inline__ int -__test_and_clear_bit(int nr, volatile void * addr) +__test_and_clear_bit(int nr, void * addr) { __u32 *p = (__u32 *) addr + (nr >> 5); __u32 m = 1 << (nr & 31);