MIPS: bitops: Use smp_mb__before_atomic in test_* ops

Use smp_mb__before_atomic() rather than smp_mb__before_llsc() in
test_and_set_bit(), test_and_clear_bit() & test_and_change_bit(). The
_atomic() versions make semantic sense in these cases, and will allow a
later patch to omit redundant barriers for Loongson3 systems that
already include a barrier within __test_bit_op().

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
This commit is contained in:
Paul Burton 2019-10-01 21:53:36 +00:00
parent 5bb29275df
commit 9026737703
No known key found for this signature in database
GPG Key ID: 3EA79FACB57500DD

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@ -209,7 +209,7 @@ static inline int test_and_set_bit_lock(unsigned long nr,
static inline int test_and_set_bit(unsigned long nr,
volatile unsigned long *addr)
{
smp_mb__before_llsc();
smp_mb__before_atomic();
return test_and_set_bit_lock(nr, addr);
}
@ -228,7 +228,7 @@ static inline int test_and_clear_bit(unsigned long nr,
int bit = nr % BITS_PER_LONG;
unsigned long res, orig;
smp_mb__before_llsc();
smp_mb__before_atomic();
if (!kernel_uses_llsc) {
res = __mips_test_and_clear_bit(nr, addr);
@ -265,7 +265,7 @@ static inline int test_and_change_bit(unsigned long nr,
int bit = nr % BITS_PER_LONG;
unsigned long res, orig;
smp_mb__before_llsc();
smp_mb__before_atomic();
if (!kernel_uses_llsc) {
res = __mips_test_and_change_bit(nr, addr);