From 5eff6ca2e39662114675e7cca6a01e15d6c0b5d1 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Wed, 16 Oct 2019 00:49:54 -0700 Subject: [PATCH] xtensa: use "m" constraint instead of "r" in futex.h assembly Use "m" constraint instead of "r" for the address, as "m" allows compiler to access adjacent locations using base + offset, while "r" requires updating the base register every time. Signed-off-by: Max Filippov --- arch/xtensa/include/asm/futex.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/xtensa/include/asm/futex.h b/arch/xtensa/include/asm/futex.h index 0c4457ca0a85..964611083224 100644 --- a/arch/xtensa/include/asm/futex.h +++ b/arch/xtensa/include/asm/futex.h @@ -43,10 +43,10 @@ #elif XCHAL_HAVE_S32C1I #define __futex_atomic_op(insn, ret, old, uaddr, arg) \ __asm__ __volatile( \ - "1: l32i %[oldval], %[addr], 0\n" \ + "1: l32i %[oldval], %[mem]\n" \ insn "\n" \ " wsr %[oldval], scompare1\n" \ - "2: s32c1i %[newval], %[addr], 0\n" \ + "2: s32c1i %[newval], %[mem]\n" \ " bne %[newval], %[oldval], 1b\n" \ " movi %[newval], 0\n" \ "3:\n" \ @@ -60,9 +60,9 @@ " .section __ex_table,\"a\"\n" \ " .long 1b, 5b, 2b, 5b\n" \ " .previous\n" \ - : [oldval] "=&r" (old), [newval] "=&r" (ret) \ - : [addr] "r" (uaddr), [oparg] "r" (arg), \ - [fault] "I" (-EFAULT) \ + : [oldval] "=&r" (old), [newval] "=&r" (ret), \ + [mem] "+m" (*(uaddr)) \ + : [oparg] "r" (arg), [fault] "I" (-EFAULT) \ : "memory") #endif