From 288e4521f0f6717909933116563e66bb894ae2af Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 3 Oct 2018 12:34:10 +0200 Subject: [PATCH] x86/asm: 'Simplify' GEN_*_RMWcc() macros Currently the GEN_*_RMWcc() macros include a return statement, which pretty much mandates we directly wrap them in a (inline) function. Macros with return statements are tricky and, as per the above, limit use, so remove the return statement and make them statement-expressions. This allows them to be used more widely. Also, shuffle the arguments a bit. Place the @cc argument as 3rd, this makes it consistent between UNARY and BINARY, but more importantly, it makes the @arg0 argument last. Since the @arg0 argument is now last, we can do CPP trickery and make it an optional argument, simplifying the users; 17 out of 18 occurences do not need this argument. Finally, change to asm symbolic names, instead of the numeric ordering of operands, which allows us to get rid of __BINARY_RMWcc_ARG and get cleaner code overall. Signed-off-by: Peter Zijlstra (Intel) Cc: JBeulich@suse.com Cc: Linus Torvalds Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: bp@alien8.de Cc: hpa@linux.intel.com Link: https://lkml.kernel.org/r/20181003130957.108960094@infradead.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/atomic.h | 8 ++-- arch/x86/include/asm/atomic64_64.h | 8 ++-- arch/x86/include/asm/bitops.h | 9 ++-- arch/x86/include/asm/local.h | 8 ++-- arch/x86/include/asm/preempt.h | 2 +- arch/x86/include/asm/refcount.h | 13 +++--- arch/x86/include/asm/rmwcc.h | 69 ++++++++++++++++++------------ 7 files changed, 64 insertions(+), 53 deletions(-) diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h index ce84388e540c..ea3d95275b43 100644 --- a/arch/x86/include/asm/atomic.h +++ b/arch/x86/include/asm/atomic.h @@ -82,7 +82,7 @@ static __always_inline void arch_atomic_sub(int i, atomic_t *v) */ static __always_inline bool arch_atomic_sub_and_test(int i, atomic_t *v) { - GEN_BINARY_RMWcc(LOCK_PREFIX "subl", v->counter, "er", i, "%0", e); + return GEN_BINARY_RMWcc(LOCK_PREFIX "subl", v->counter, e, "er", i); } #define arch_atomic_sub_and_test arch_atomic_sub_and_test @@ -122,7 +122,7 @@ static __always_inline void arch_atomic_dec(atomic_t *v) */ static __always_inline bool arch_atomic_dec_and_test(atomic_t *v) { - GEN_UNARY_RMWcc(LOCK_PREFIX "decl", v->counter, "%0", e); + return GEN_UNARY_RMWcc(LOCK_PREFIX "decl", v->counter, e); } #define arch_atomic_dec_and_test arch_atomic_dec_and_test @@ -136,7 +136,7 @@ static __always_inline bool arch_atomic_dec_and_test(atomic_t *v) */ static __always_inline bool arch_atomic_inc_and_test(atomic_t *v) { - GEN_UNARY_RMWcc(LOCK_PREFIX "incl", v->counter, "%0", e); + return GEN_UNARY_RMWcc(LOCK_PREFIX "incl", v->counter, e); } #define arch_atomic_inc_and_test arch_atomic_inc_and_test @@ -151,7 +151,7 @@ static __always_inline bool arch_atomic_inc_and_test(atomic_t *v) */ static __always_inline bool arch_atomic_add_negative(int i, atomic_t *v) { - GEN_BINARY_RMWcc(LOCK_PREFIX "addl", v->counter, "er", i, "%0", s); + return GEN_BINARY_RMWcc(LOCK_PREFIX "addl", v->counter, s, "er", i); } #define arch_atomic_add_negative arch_atomic_add_negative diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h index 5f851d92eecd..dadc20adba21 100644 --- a/arch/x86/include/asm/atomic64_64.h +++ b/arch/x86/include/asm/atomic64_64.h @@ -73,7 +73,7 @@ static inline void arch_atomic64_sub(long i, atomic64_t *v) */ static inline bool arch_atomic64_sub_and_test(long i, atomic64_t *v) { - GEN_BINARY_RMWcc(LOCK_PREFIX "subq", v->counter, "er", i, "%0", e); + return GEN_BINARY_RMWcc(LOCK_PREFIX "subq", v->counter, e, "er", i); } #define arch_atomic64_sub_and_test arch_atomic64_sub_and_test @@ -115,7 +115,7 @@ static __always_inline void arch_atomic64_dec(atomic64_t *v) */ static inline bool arch_atomic64_dec_and_test(atomic64_t *v) { - GEN_UNARY_RMWcc(LOCK_PREFIX "decq", v->counter, "%0", e); + return GEN_UNARY_RMWcc(LOCK_PREFIX "decq", v->counter, e); } #define arch_atomic64_dec_and_test arch_atomic64_dec_and_test @@ -129,7 +129,7 @@ static inline bool arch_atomic64_dec_and_test(atomic64_t *v) */ static inline bool arch_atomic64_inc_and_test(atomic64_t *v) { - GEN_UNARY_RMWcc(LOCK_PREFIX "incq", v->counter, "%0", e); + return GEN_UNARY_RMWcc(LOCK_PREFIX "incq", v->counter, e); } #define arch_atomic64_inc_and_test arch_atomic64_inc_and_test @@ -144,7 +144,7 @@ static inline bool arch_atomic64_inc_and_test(atomic64_t *v) */ static inline bool arch_atomic64_add_negative(long i, atomic64_t *v) { - GEN_BINARY_RMWcc(LOCK_PREFIX "addq", v->counter, "er", i, "%0", s); + return GEN_BINARY_RMWcc(LOCK_PREFIX "addq", v->counter, s, "er", i); } #define arch_atomic64_add_negative arch_atomic64_add_negative diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h index 9f645ba57dbb..124f9195eb3e 100644 --- a/arch/x86/include/asm/bitops.h +++ b/arch/x86/include/asm/bitops.h @@ -217,8 +217,7 @@ static __always_inline void change_bit(long nr, volatile unsigned long *addr) */ static __always_inline bool test_and_set_bit(long nr, volatile unsigned long *addr) { - GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts), - *addr, "Ir", nr, "%0", c); + return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts), *addr, c, "Ir", nr); } /** @@ -264,8 +263,7 @@ static __always_inline bool __test_and_set_bit(long nr, volatile unsigned long * */ static __always_inline bool test_and_clear_bit(long nr, volatile unsigned long *addr) { - GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btr), - *addr, "Ir", nr, "%0", c); + return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btr), *addr, c, "Ir", nr); } /** @@ -318,8 +316,7 @@ static __always_inline bool __test_and_change_bit(long nr, volatile unsigned lon */ static __always_inline bool test_and_change_bit(long nr, volatile unsigned long *addr) { - GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btc), - *addr, "Ir", nr, "%0", c); + return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btc), *addr, c, "Ir", nr); } static __always_inline bool constant_test_bit(long nr, const volatile unsigned long *addr) diff --git a/arch/x86/include/asm/local.h b/arch/x86/include/asm/local.h index c91083c59845..349a47acaa4a 100644 --- a/arch/x86/include/asm/local.h +++ b/arch/x86/include/asm/local.h @@ -53,7 +53,7 @@ static inline void local_sub(long i, local_t *l) */ static inline bool local_sub_and_test(long i, local_t *l) { - GEN_BINARY_RMWcc(_ASM_SUB, l->a.counter, "er", i, "%0", e); + return GEN_BINARY_RMWcc(_ASM_SUB, l->a.counter, e, "er", i); } /** @@ -66,7 +66,7 @@ static inline bool local_sub_and_test(long i, local_t *l) */ static inline bool local_dec_and_test(local_t *l) { - GEN_UNARY_RMWcc(_ASM_DEC, l->a.counter, "%0", e); + return GEN_UNARY_RMWcc(_ASM_DEC, l->a.counter, e); } /** @@ -79,7 +79,7 @@ static inline bool local_dec_and_test(local_t *l) */ static inline bool local_inc_and_test(local_t *l) { - GEN_UNARY_RMWcc(_ASM_INC, l->a.counter, "%0", e); + return GEN_UNARY_RMWcc(_ASM_INC, l->a.counter, e); } /** @@ -93,7 +93,7 @@ static inline bool local_inc_and_test(local_t *l) */ static inline bool local_add_negative(long i, local_t *l) { - GEN_BINARY_RMWcc(_ASM_ADD, l->a.counter, "er", i, "%0", s); + return GEN_BINARY_RMWcc(_ASM_ADD, l->a.counter, s, "er", i); } /** diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h index 7f2dbd91fc74..90cb2f36c042 100644 --- a/arch/x86/include/asm/preempt.h +++ b/arch/x86/include/asm/preempt.h @@ -88,7 +88,7 @@ static __always_inline void __preempt_count_sub(int val) */ static __always_inline bool __preempt_count_dec_and_test(void) { - GEN_UNARY_RMWcc("decl", __preempt_count, __percpu_arg(0), e); + return GEN_UNARY_RMWcc("decl", __preempt_count, e, __percpu_arg([var])); } /* diff --git a/arch/x86/include/asm/refcount.h b/arch/x86/include/asm/refcount.h index c92909da0686..a8b5e1e13319 100644 --- a/arch/x86/include/asm/refcount.h +++ b/arch/x86/include/asm/refcount.h @@ -79,16 +79,17 @@ static __always_inline void refcount_dec(refcount_t *r) static __always_inline __must_check bool refcount_sub_and_test(unsigned int i, refcount_t *r) { - GEN_BINARY_SUFFIXED_RMWcc(LOCK_PREFIX "subl", - "REFCOUNT_CHECK_LT_ZERO counter=\"%0\"", - r->refs.counter, "er", i, "%0", e, "cx"); + + return GEN_BINARY_SUFFIXED_RMWcc(LOCK_PREFIX "subl", + "REFCOUNT_CHECK_LT_ZERO counter=\"%[var]\"", + r->refs.counter, e, "er", i, "cx"); } static __always_inline __must_check bool refcount_dec_and_test(refcount_t *r) { - GEN_UNARY_SUFFIXED_RMWcc(LOCK_PREFIX "decl", - "REFCOUNT_CHECK_LT_ZERO counter=\"%0\"", - r->refs.counter, "%0", e, "cx"); + return GEN_UNARY_SUFFIXED_RMWcc(LOCK_PREFIX "decl", + "REFCOUNT_CHECK_LT_ZERO counter=\"%[var]\"", + r->refs.counter, e, "cx"); } static __always_inline __must_check diff --git a/arch/x86/include/asm/rmwcc.h b/arch/x86/include/asm/rmwcc.h index 4914a3e7c803..46ac84b506f5 100644 --- a/arch/x86/include/asm/rmwcc.h +++ b/arch/x86/include/asm/rmwcc.h @@ -2,56 +2,69 @@ #ifndef _ASM_X86_RMWcc #define _ASM_X86_RMWcc +/* This counts to 12. Any more, it will return 13th argument. */ +#define __RMWcc_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n +#define RMWcc_ARGS(X...) __RMWcc_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) + +#define __RMWcc_CONCAT(a, b) a ## b +#define RMWcc_CONCAT(a, b) __RMWcc_CONCAT(a, b) + #define __CLOBBERS_MEM(clb...) "memory", ## clb #if !defined(__GCC_ASM_FLAG_OUTPUTS__) && defined(CC_HAVE_ASM_GOTO) /* Use asm goto */ -#define __GEN_RMWcc(fullop, var, cc, clobbers, ...) \ -do { \ +#define __GEN_RMWcc(fullop, _var, cc, clobbers, ...) \ +({ \ + bool c = false; \ asm_volatile_goto (fullop "; j" #cc " %l[cc_label]" \ - : : [counter] "m" (var), ## __VA_ARGS__ \ + : : [var] "m" (_var), ## __VA_ARGS__ \ : clobbers : cc_label); \ - return 0; \ -cc_label: \ - return 1; \ -} while (0) - -#define __BINARY_RMWcc_ARG " %1, " - + if (0) { \ +cc_label: c = true; \ + } \ + c; \ +}) #else /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */ /* Use flags output or a set instruction */ -#define __GEN_RMWcc(fullop, var, cc, clobbers, ...) \ -do { \ +#define __GEN_RMWcc(fullop, _var, cc, clobbers, ...) \ +({ \ bool c; \ asm volatile (fullop CC_SET(cc) \ - : [counter] "+m" (var), CC_OUT(cc) (c) \ + : [var] "+m" (_var), CC_OUT(cc) (c) \ : __VA_ARGS__ : clobbers); \ - return c; \ -} while (0) - -#define __BINARY_RMWcc_ARG " %2, " + c; \ +}) #endif /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */ -#define GEN_UNARY_RMWcc(op, var, arg0, cc) \ +#define GEN_UNARY_RMWcc_4(op, var, cc, arg0) \ __GEN_RMWcc(op " " arg0, var, cc, __CLOBBERS_MEM()) -#define GEN_UNARY_SUFFIXED_RMWcc(op, suffix, var, arg0, cc, clobbers...)\ - __GEN_RMWcc(op " " arg0 "\n\t" suffix, var, cc, \ - __CLOBBERS_MEM(clobbers)) +#define GEN_UNARY_RMWcc_3(op, var, cc) \ + GEN_UNARY_RMWcc_4(op, var, cc, "%[var]") -#define GEN_BINARY_RMWcc(op, var, vcon, val, arg0, cc) \ - __GEN_RMWcc(op __BINARY_RMWcc_ARG arg0, var, cc, \ - __CLOBBERS_MEM(), vcon (val)) +#define GEN_UNARY_RMWcc(X...) RMWcc_CONCAT(GEN_UNARY_RMWcc_, RMWcc_ARGS(X))(X) + +#define GEN_BINARY_RMWcc_6(op, var, cc, vcon, _val, arg0) \ + __GEN_RMWcc(op " %[val], " arg0, var, cc, \ + __CLOBBERS_MEM(), [val] vcon (_val)) + +#define GEN_BINARY_RMWcc_5(op, var, cc, vcon, val) \ + GEN_BINARY_RMWcc_6(op, var, cc, vcon, val, "%[var]") + +#define GEN_BINARY_RMWcc(X...) RMWcc_CONCAT(GEN_BINARY_RMWcc_, RMWcc_ARGS(X))(X) + +#define GEN_UNARY_SUFFIXED_RMWcc(op, suffix, var, cc, clobbers...) \ + __GEN_RMWcc(op " %[var]\n\t" suffix, var, cc, \ + __CLOBBERS_MEM(clobbers)) -#define GEN_BINARY_SUFFIXED_RMWcc(op, suffix, var, vcon, val, arg0, cc, \ - clobbers...) \ - __GEN_RMWcc(op __BINARY_RMWcc_ARG arg0 "\n\t" suffix, var, cc, \ - __CLOBBERS_MEM(clobbers), vcon (val)) +#define GEN_BINARY_SUFFIXED_RMWcc(op, suffix, var, cc, vcon, _val, clobbers...)\ + __GEN_RMWcc(op " %[val], %[var]\n\t" suffix, var, cc, \ + __CLOBBERS_MEM(clobbers), [val] vcon (_val)) #endif /* _ASM_X86_RMWcc */ -- 2.39.2