Generate the sync instructions required to workaround Loongson3 LL/SC errata within inline asm blocks, which feels a little safer than doing it from C where strictly speaking the compiler would be well within its rights to insert a memory access between the separate asm statements we previously had, containing sync & ll instructions respectively.
Signed-off-by: Paul Burton <paul.bur...@mips.com> --- arch/mips/include/asm/futex.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/mips/include/asm/futex.h b/arch/mips/include/asm/futex.h index b83b0397462d..45c3e3652f48 100644 --- a/arch/mips/include/asm/futex.h +++ b/arch/mips/include/asm/futex.h @@ -16,6 +16,7 @@ #include <asm/barrier.h> #include <asm/compiler.h> #include <asm/errno.h> +#include <asm/sync.h> #include <asm/war.h> #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ @@ -50,12 +51,12 @@ "i" (-EFAULT) \ : "memory"); \ } else if (cpu_has_llsc) { \ - loongson_llsc_mb(); \ __asm__ __volatile__( \ " .set push \n" \ " .set noat \n" \ " .set push \n" \ " .set "MIPS_ISA_ARCH_LEVEL" \n" \ + " " __SYNC(full, loongson3_war) " \n" \ "1: "user_ll("%1", "%4")" # __futex_atomic_op\n" \ " .set pop \n" \ " " insn " \n" \ @@ -164,13 +165,13 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, "i" (-EFAULT) : "memory"); } else if (cpu_has_llsc) { - loongson_llsc_mb(); __asm__ __volatile__( "# futex_atomic_cmpxchg_inatomic \n" " .set push \n" " .set noat \n" " .set push \n" " .set "MIPS_ISA_ARCH_LEVEL" \n" + " " __SYNC(full, loongson3_war) " \n" "1: "user_ll("%1", "%3")" \n" " bne %1, %z4, 3f \n" " .set pop \n" @@ -178,8 +179,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, " .set "MIPS_ISA_ARCH_LEVEL" \n" "2: "user_sc("$1", "%2")" \n" " beqz $1, 1b \n" - __WEAK_LLSC_MB - "3: \n" + "3: " __SYNC_ELSE(full, loongson3_war, __WEAK_LLSC_MB) "\n" " .insn \n" " .set pop \n" " .section .fixup,\"ax\" \n" @@ -194,7 +194,6 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, : GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval), "i" (-EFAULT) : "memory"); - loongson_llsc_mb(); } else return -ENOSYS; -- 2.23.0