Merge "arm64: rwlocks: retry trylock operation if strex fails on free lock" (5a6b7186) · Commits · e / devices / android_kernel_sony_msm8994

arch/arm64/include/asm/spinlock.h

+4 −2

Original line number	Diff line number	Diff line
		@@ -140,9 +140,10 @@ static inline int arch_write_trylock(arch_rwlock_t *rw)
		unsigned int tmp;

		asm volatile(
		" ldaxr %w0, %1\n"
		"2: ldaxr %w0, %1\n"
		" cbnz %w0, 1f\n"
		" stxr %w0, %w2, %1\n"
		" cbnz %w0, 2b\n"
		"1:\n"
		: "=&r" (tmp), "+Q" (rw->lock)
		: "r" (0x80000000)
		@@ -209,10 +210,11 @@ static inline int arch_read_trylock(arch_rwlock_t *rw)
		unsigned int tmp, tmp2 = 1;

		asm volatile(
		" ldaxr %w0, %2\n"
		"2: ldaxr %w0, %2\n"
		" add %w0, %w0, #1\n"
		" tbnz %w0, #31, 1f\n"
		" stxr %w1, %w0, %2\n"
		" cbnz %w1, 2b\n"
		"1:\n"
		: "=&r" (tmp), "+r" (tmp2), "+Q" (rw->lock)
		: