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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Aug 29, 2019 at 04:48:34PM +0100, Will Deacon wrote: > diff --git a/arch/arm64/include/asm/atomic_ll_sc.h b/arch/arm64/include/asm/atomic_ll_sc.h > index 95091f72228b..7fa042f5444e 100644 > --- a/arch/arm64/include/asm/atomic_ll_sc.h > +++ b/arch/arm64/include/asm/atomic_ll_sc.h > @@ -23,6 +23,10 @@ asm_ops "\n" \ > #define __LL_SC_FALLBACK(asm_ops) asm_ops > #endif > > +#ifndef CONFIG_CC_HAS_K_CONSTRAINT > +#define K > +#endif Bah, I need to use something like __stringify when the constraint is used in order for this to get expanded properly. Updated diff below. Will --->8 diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 61de992bbea3..0cef056b5fb1 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -39,6 +39,12 @@ $(warning LSE atomics not supported by binutils) endif endif +cc_has_k_constraint := $(call try-run,echo \ + 'int main(void) { \ + asm volatile("and w0, w0, %w0" :: "K" (4294967295)); \ + return 0; \ + }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1) + ifeq ($(CONFIG_ARM64), y) brokengasinst := $(call as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n,,-DCONFIG_BROKEN_GAS_INST=1) @@ -63,7 +69,8 @@ ifeq ($(CONFIG_GENERIC_COMPAT_VDSO), y) endif endif -KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr) $(brokengasinst) $(compat_vdso) +KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr) $(brokengasinst) \ + $(compat_vdso) $(cc_has_k_constraint) KBUILD_CFLAGS += -fno-asynchronous-unwind-tables KBUILD_CFLAGS += $(call cc-disable-warning, psabi) KBUILD_AFLAGS += $(lseinstr) $(brokengasinst) $(compat_vdso) diff --git a/arch/arm64/include/asm/atomic_ll_sc.h b/arch/arm64/include/asm/atomic_ll_sc.h index 95091f72228b..7b012148bfd6 100644 --- a/arch/arm64/include/asm/atomic_ll_sc.h +++ b/arch/arm64/include/asm/atomic_ll_sc.h @@ -10,6 +10,8 @@ #ifndef __ASM_ATOMIC_LL_SC_H #define __ASM_ATOMIC_LL_SC_H +#include + #if IS_ENABLED(CONFIG_ARM64_LSE_ATOMICS) && IS_ENABLED(CONFIG_AS_LSE) #define __LL_SC_FALLBACK(asm_ops) \ " b 3f\n" \ @@ -23,6 +25,10 @@ asm_ops "\n" \ #define __LL_SC_FALLBACK(asm_ops) asm_ops #endif +#ifndef CONFIG_CC_HAS_K_CONSTRAINT +#define K +#endif + /* * AArch64 UP and SMP safe atomic ops. We use load exclusive and * store exclusive to ensure that these are atomic. We may loop @@ -44,7 +50,7 @@ __ll_sc_atomic_##op(int i, atomic_t *v) \ " stxr %w1, %w0, %2\n" \ " cbnz %w1, 1b\n") \ : "=&r" (result), "=&r" (tmp), "+Q" (v->counter) \ - : #constraint "r" (i)); \ + : __stringify(constraint) "r" (i)); \ } #define ATOMIC_OP_RETURN(name, mb, acq, rel, cl, op, asm_op, constraint)\ @@ -63,7 +69,7 @@ __ll_sc_atomic_##op##_return##name(int i, atomic_t *v) \ " cbnz %w1, 1b\n" \ " " #mb ) \ : "=&r" (result), "=&r" (tmp), "+Q" (v->counter) \ - : #constraint "r" (i) \ + : __stringify(constraint) "r" (i) \ : cl); \ \ return result; \ @@ -85,7 +91,7 @@ __ll_sc_atomic_fetch_##op##name(int i, atomic_t *v) \ " cbnz %w2, 1b\n" \ " " #mb ) \ : "=&r" (result), "=&r" (val), "=&r" (tmp), "+Q" (v->counter) \ - : #constraint "r" (i) \ + : __stringify(constraint) "r" (i) \ : cl); \ \ return result; \ @@ -113,10 +119,15 @@ ATOMIC_OPS(sub, sub, J) ATOMIC_FETCH_OP (_acquire, , a, , "memory", __VA_ARGS__)\ ATOMIC_FETCH_OP (_release, , , l, "memory", __VA_ARGS__) -ATOMIC_OPS(and, and, ) +ATOMIC_OPS(and, and, K) +ATOMIC_OPS(or, orr, K) +ATOMIC_OPS(xor, eor, K) +/* + * GAS converts the mysterious and undocumented BIC (immediate) alias to + * an AND (immediate) instruction with the immediate inverted. We don't + * have a constraint for this, so fall back to register. + */ ATOMIC_OPS(andnot, bic, ) -ATOMIC_OPS(or, orr, ) -ATOMIC_OPS(xor, eor, ) #undef ATOMIC_OPS #undef ATOMIC_FETCH_OP @@ -138,7 +149,7 @@ __ll_sc_atomic64_##op(s64 i, atomic64_t *v) \ " stxr %w1, %0, %2\n" \ " cbnz %w1, 1b") \ : "=&r" (result), "=&r" (tmp), "+Q" (v->counter) \ - : #constraint "r" (i)); \ + : __stringify(constraint) "r" (i)); \ } #define ATOMIC64_OP_RETURN(name, mb, acq, rel, cl, op, asm_op, constraint)\ @@ -157,7 +168,7 @@ __ll_sc_atomic64_##op##_return##name(s64 i, atomic64_t *v) \ " cbnz %w1, 1b\n" \ " " #mb ) \ : "=&r" (result), "=&r" (tmp), "+Q" (v->counter) \ - : #constraint "r" (i) \ + : __stringify(constraint) "r" (i) \ : cl); \ \ return result; \ @@ -179,7 +190,7 @@ __ll_sc_atomic64_fetch_##op##name(s64 i, atomic64_t *v) \ " cbnz %w2, 1b\n" \ " " #mb ) \ : "=&r" (result), "=&r" (val), "=&r" (tmp), "+Q" (v->counter) \ - : #constraint "r" (i) \ + : __stringify(constraint) "r" (i) \ : cl); \ \ return result; \ @@ -208,9 +219,14 @@ ATOMIC64_OPS(sub, sub, J) ATOMIC64_FETCH_OP (_release,, , l, "memory", __VA_ARGS__) ATOMIC64_OPS(and, and, L) -ATOMIC64_OPS(andnot, bic, ) ATOMIC64_OPS(or, orr, L) ATOMIC64_OPS(xor, eor, L) +/* + * GAS converts the mysterious and undocumented BIC (immediate) alias to + * an AND (immediate) instruction with the immediate inverted. We don't + * have a constraint for this, so fall back to register. + */ +ATOMIC64_OPS(andnot, bic, ) #undef ATOMIC64_OPS #undef ATOMIC64_FETCH_OP @@ -269,7 +285,7 @@ __ll_sc__cmpxchg_case_##name##sz(volatile void *ptr, \ "2:") \ : [tmp] "=&r" (tmp), [oldval] "=&r" (oldval), \ [v] "+Q" (*(u##sz *)ptr) \ - : [old] #constraint "r" (old), [new] "r" (new) \ + : [old] __stringify(constraint) "r" (old), [new] "r" (new) \ : cl); \ \ return oldval; \ @@ -280,21 +296,21 @@ __ll_sc__cmpxchg_case_##name##sz(volatile void *ptr, \ * handle the 'K' constraint for the value 4294967295 - thus we use no * constraint for 32 bit operations. */ -__CMPXCHG_CASE(w, b, , 8, , , , , ) -__CMPXCHG_CASE(w, h, , 16, , , , , ) -__CMPXCHG_CASE(w, , , 32, , , , , ) +__CMPXCHG_CASE(w, b, , 8, , , , , K) +__CMPXCHG_CASE(w, h, , 16, , , , , K) +__CMPXCHG_CASE(w, , , 32, , , , , K) __CMPXCHG_CASE( , , , 64, , , , , L) -__CMPXCHG_CASE(w, b, acq_, 8, , a, , "memory", ) -__CMPXCHG_CASE(w, h, acq_, 16, , a, , "memory", ) -__CMPXCHG_CASE(w, , acq_, 32, , a, , "memory", ) +__CMPXCHG_CASE(w, b, acq_, 8, , a, , "memory", K) +__CMPXCHG_CASE(w, h, acq_, 16, , a, , "memory", K) +__CMPXCHG_CASE(w, , acq_, 32, , a, , "memory", K) __CMPXCHG_CASE( , , acq_, 64, , a, , "memory", L) -__CMPXCHG_CASE(w, b, rel_, 8, , , l, "memory", ) -__CMPXCHG_CASE(w, h, rel_, 16, , , l, "memory", ) -__CMPXCHG_CASE(w, , rel_, 32, , , l, "memory", ) +__CMPXCHG_CASE(w, b, rel_, 8, , , l, "memory", K) +__CMPXCHG_CASE(w, h, rel_, 16, , , l, "memory", K) +__CMPXCHG_CASE(w, , rel_, 32, , , l, "memory", K) __CMPXCHG_CASE( , , rel_, 64, , , l, "memory", L) -__CMPXCHG_CASE(w, b, mb_, 8, dmb ish, , l, "memory", ) -__CMPXCHG_CASE(w, h, mb_, 16, dmb ish, , l, "memory", ) -__CMPXCHG_CASE(w, , mb_, 32, dmb ish, , l, "memory", ) +__CMPXCHG_CASE(w, b, mb_, 8, dmb ish, , l, "memory", K) +__CMPXCHG_CASE(w, h, mb_, 16, dmb ish, , l, "memory", K) +__CMPXCHG_CASE(w, , mb_, 32, dmb ish, , l, "memory", K) __CMPXCHG_CASE( , , mb_, 64, dmb ish, , l, "memory", L) #undef __CMPXCHG_CASE @@ -332,5 +348,6 @@ __CMPXCHG_DBL( , , , ) __CMPXCHG_DBL(_mb, dmb ish, l, "memory") #undef __CMPXCHG_DBL +#undef K #endif /* __ASM_ATOMIC_LL_SC_H */ _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel