From 5753762cbd1cb208f6e6c916169b56139373b790 Mon Sep 17 00:00:00 2001 From: Markos Chandras Date: Mon, 24 Nov 2014 14:11:39 +0000 Subject: [PATCH] MIPS: asm: spinlock: Replace "sub" instruction with "addiu" "sub $reg, imm" is not a real MIPS instruction. The assembler can replace that with "addi $reg, -imm". However, addi has been removed from R6, so we replace the "sub" instruction with the "addiu" one. Signed-off-by: Markos Chandras --- arch/mips/include/asm/spinlock.h | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/mips/include/asm/spinlock.h b/arch/mips/include/asm/spinlock.h index b5238404c059..b4548690ade9 100644 --- a/arch/mips/include/asm/spinlock.h +++ b/arch/mips/include/asm/spinlock.h @@ -254,9 +254,6 @@ static inline void arch_read_lock(arch_rwlock_t *rw) smp_llsc_mb(); } -/* Note the use of sub, not subu which will make the kernel die with an - overflow exception if we ever try to unlock an rwlock that is already - unlocked or is being held by a writer. */ static inline void arch_read_unlock(arch_rwlock_t *rw) { unsigned int tmp; @@ -266,7 +263,7 @@ static inline void arch_read_unlock(arch_rwlock_t *rw) if (R10000_LLSC_WAR) { __asm__ __volatile__( "1: ll %1, %2 # arch_read_unlock \n" - " sub %1, 1 \n" + " addiu %1, 1 \n" " sc %1, %0 \n" " beqzl %1, 1b \n" : "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp) @@ -276,7 +273,7 @@ static inline void arch_read_unlock(arch_rwlock_t *rw) do { __asm__ __volatile__( "1: ll %1, %2 # arch_read_unlock \n" - " sub %1, 1 \n" + " addiu %1, -1 \n" " sc %1, %0 \n" : "=" GCC_OFF_SMALL_ASM() (rw->lock), "=&r" (tmp) : GCC_OFF_SMALL_ASM() (rw->lock) -- 2.20.1