From 6f6ed482653723e53da4a57b200348ac1eed5ce9 Mon Sep 17 00:00:00 2001 From: Leonid Yegoshin Date: Mon, 1 Jun 2015 17:09:52 -0700 Subject: MIPS: Replace smp_mb with release barrier function in unlocks. Repleace smp_mb() in arch_write_unlock() and __clear_bit_unlock() to smp_mb__before_llsc() call which does "release" barrier functionality. It seems like it was missed in commit f252ffd50c97dae87b45f1dbad24f71358ccfbd6 during introduction of "acquire" and "release" semantics. [ralf@linux-mips: The original patch submission was labelled a fix but actually it replaces a barrier with another less restrictive type of barrier so it doesn't fix any ill behaviour but rather squeezes out a tad better performance. Further improvments will be possible once smp_release() has been merged.] Signed-off-by: Leonid Yegoshin Cc: linux-mips@linux-mips.org Cc: benh@kernel.crashing.org Cc: will.deacon@arm.com Cc: linux-kernel@vger.kernel.org Cc: markos.chandras@imgtec.com Cc: macro@linux-mips.org Cc: Steven.Hill@imgtec.com Cc: alexander.h.duyck@redhat.com Cc: davem@davemloft.net Patchwork: https://patchwork.linux-mips.org/patch/10507/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/spinlock.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/mips/include/asm/spinlock.h') diff --git a/arch/mips/include/asm/spinlock.h b/arch/mips/include/asm/spinlock.h index 1fca2e0793dc..7c7f3b2bd3de 100644 --- a/arch/mips/include/asm/spinlock.h +++ b/arch/mips/include/asm/spinlock.h @@ -317,7 +317,7 @@ static inline void arch_write_lock(arch_rwlock_t *rw) static inline void arch_write_unlock(arch_rwlock_t *rw) { - smp_mb(); + smp_mb__before_llsc(); __asm__ __volatile__( " # arch_write_unlock \n" -- cgit v1.2.3 From 9ff897c4e8d5bd05ad7009f84a395596d4953858 Mon Sep 17 00:00:00 2001 From: Markos Chandras Date: Mon, 20 Apr 2015 10:54:34 +0100 Subject: MIPS: spinlock: Adjust arch_spin_lock back-off time Make it similar to the trylock and R10000_LLSC_WAR cases. Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9789/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/spinlock.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/mips/include/asm/spinlock.h') diff --git a/arch/mips/include/asm/spinlock.h b/arch/mips/include/asm/spinlock.h index 7c7f3b2bd3de..9de4ba43dcd1 100644 --- a/arch/mips/include/asm/spinlock.h +++ b/arch/mips/include/asm/spinlock.h @@ -109,7 +109,7 @@ static inline void arch_spin_lock(arch_spinlock_t *lock) " subu %[ticket], %[my_ticket], %[ticket] \n" "2: \n" " .subsection 2 \n" - "4: andi %[ticket], %[ticket], 0x1fff \n" + "4: andi %[ticket], %[ticket], 0xffff \n" " sll %[ticket], 5 \n" " \n" "6: bnez %[ticket], 6b \n" -- cgit v1.2.3