From: Leonardo Bras Date: Wed, 3 Jan 2024 16:32:00 +0000 (-0300) Subject: riscv/cmpxchg: Deduplicate cmpxchg() asm and macros X-Git-Tag: v6.10-rc1~52^2~14^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=07a0a41cb77d582e4db05bd9e79daa145d5d6ea4;p=thirdparty%2Fkernel%2Flinux.git riscv/cmpxchg: Deduplicate cmpxchg() asm and macros In this header every cmpxchg define (_relaxed, _acquire, _release, vanilla) contain it's own asm file, both for 4-byte variables an 8-byte variables, on a total of 8 versions of mostly the same asm. This is usually bad, as it means any change may be done in up to 8 different places. Unify those versions by creating a new define with enough parameters to generate any version of the previous 8. Then unify the result under a more general define, and simplify arch_cmpxchg* generation (This did not cause any change in generated asm) Signed-off-by: Leonardo Bras Reviewed-by: Guo Ren Reviewed-by: Andrea Parri Tested-by: Guo Ren Link: https://lore.kernel.org/r/20240103163203.72768-4-leobras@redhat.com Signed-off-by: Palmer Dabbelt --- diff --git a/arch/riscv/include/asm/cmpxchg.h b/arch/riscv/include/asm/cmpxchg.h index 48478a8eecee7..e3e0ac7ba061b 100644 --- a/arch/riscv/include/asm/cmpxchg.h +++ b/arch/riscv/include/asm/cmpxchg.h @@ -71,190 +71,61 @@ * store NEW in MEM. Return the initial value in MEM. Success is * indicated by comparing RETURN with OLD. */ -#define __cmpxchg_relaxed(ptr, old, new, size) \ -({ \ - __typeof__(ptr) __ptr = (ptr); \ - __typeof__(*(ptr)) __old = (old); \ - __typeof__(*(ptr)) __new = (new); \ - __typeof__(*(ptr)) __ret; \ - register unsigned int __rc; \ - switch (size) { \ - case 4: \ - __asm__ __volatile__ ( \ - "0: lr.w %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.w %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" ((long)__old), "rJ" (__new) \ - : "memory"); \ - break; \ - case 8: \ - __asm__ __volatile__ ( \ - "0: lr.d %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.d %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" (__old), "rJ" (__new) \ - : "memory"); \ - break; \ - default: \ - BUILD_BUG(); \ - } \ - __ret; \ -}) -#define arch_cmpxchg_relaxed(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) _o_ = (o); \ - __typeof__(*(ptr)) _n_ = (n); \ - (__typeof__(*(ptr))) __cmpxchg_relaxed((ptr), \ - _o_, _n_, sizeof(*(ptr))); \ -}) -#define __cmpxchg_acquire(ptr, old, new, size) \ +#define __arch_cmpxchg(lr_sfx, sc_sfx, prepend, append, r, p, co, o, n) \ ({ \ - __typeof__(ptr) __ptr = (ptr); \ - __typeof__(*(ptr)) __old = (old); \ - __typeof__(*(ptr)) __new = (new); \ - __typeof__(*(ptr)) __ret; \ register unsigned int __rc; \ - switch (size) { \ - case 4: \ - __asm__ __volatile__ ( \ - "0: lr.w %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.w %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - RISCV_ACQUIRE_BARRIER \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" ((long)__old), "rJ" (__new) \ - : "memory"); \ - break; \ - case 8: \ - __asm__ __volatile__ ( \ - "0: lr.d %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.d %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - RISCV_ACQUIRE_BARRIER \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" (__old), "rJ" (__new) \ - : "memory"); \ - break; \ - default: \ - BUILD_BUG(); \ - } \ - __ret; \ -}) - -#define arch_cmpxchg_acquire(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) _o_ = (o); \ - __typeof__(*(ptr)) _n_ = (n); \ - (__typeof__(*(ptr))) __cmpxchg_acquire((ptr), \ - _o_, _n_, sizeof(*(ptr))); \ + \ + __asm__ __volatile__ ( \ + prepend \ + "0: lr" lr_sfx " %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc" sc_sfx " %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + append \ + "1:\n" \ + : "=&r" (r), "=&r" (__rc), "+A" (*(p)) \ + : "rJ" (co o), "rJ" (n) \ + : "memory"); \ }) -#define __cmpxchg_release(ptr, old, new, size) \ +#define _arch_cmpxchg(ptr, old, new, sc_sfx, prepend, append) \ ({ \ __typeof__(ptr) __ptr = (ptr); \ - __typeof__(*(ptr)) __old = (old); \ - __typeof__(*(ptr)) __new = (new); \ - __typeof__(*(ptr)) __ret; \ - register unsigned int __rc; \ - switch (size) { \ + __typeof__(*(__ptr)) __old = (old); \ + __typeof__(*(__ptr)) __new = (new); \ + __typeof__(*(__ptr)) __ret; \ + \ + switch (sizeof(*__ptr)) { \ case 4: \ - __asm__ __volatile__ ( \ - RISCV_RELEASE_BARRIER \ - "0: lr.w %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.w %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" ((long)__old), "rJ" (__new) \ - : "memory"); \ + __arch_cmpxchg(".w", ".w" sc_sfx, prepend, append, \ + __ret, __ptr, (long), __old, __new); \ break; \ case 8: \ - __asm__ __volatile__ ( \ - RISCV_RELEASE_BARRIER \ - "0: lr.d %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.d %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" (__old), "rJ" (__new) \ - : "memory"); \ + __arch_cmpxchg(".d", ".d" sc_sfx, prepend, append, \ + __ret, __ptr, /**/, __old, __new); \ break; \ default: \ BUILD_BUG(); \ } \ - __ret; \ + (__typeof__(*(__ptr)))__ret; \ }) -#define arch_cmpxchg_release(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) _o_ = (o); \ - __typeof__(*(ptr)) _n_ = (n); \ - (__typeof__(*(ptr))) __cmpxchg_release((ptr), \ - _o_, _n_, sizeof(*(ptr))); \ -}) +#define arch_cmpxchg_relaxed(ptr, o, n) \ + _arch_cmpxchg((ptr), (o), (n), "", "", "") -#define __cmpxchg(ptr, old, new, size) \ -({ \ - __typeof__(ptr) __ptr = (ptr); \ - __typeof__(*(ptr)) __old = (old); \ - __typeof__(*(ptr)) __new = (new); \ - __typeof__(*(ptr)) __ret; \ - register unsigned int __rc; \ - switch (size) { \ - case 4: \ - __asm__ __volatile__ ( \ - "0: lr.w %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.w.rl %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - " fence rw, rw\n" \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" ((long)__old), "rJ" (__new) \ - : "memory"); \ - break; \ - case 8: \ - __asm__ __volatile__ ( \ - "0: lr.d %0, %2\n" \ - " bne %0, %z3, 1f\n" \ - " sc.d.rl %1, %z4, %2\n" \ - " bnez %1, 0b\n" \ - " fence rw, rw\n" \ - "1:\n" \ - : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ - : "rJ" (__old), "rJ" (__new) \ - : "memory"); \ - break; \ - default: \ - BUILD_BUG(); \ - } \ - __ret; \ -}) +#define arch_cmpxchg_acquire(ptr, o, n) \ + _arch_cmpxchg((ptr), (o), (n), "", "", RISCV_ACQUIRE_BARRIER) + +#define arch_cmpxchg_release(ptr, o, n) \ + _arch_cmpxchg((ptr), (o), (n), "", RISCV_RELEASE_BARRIER, "") #define arch_cmpxchg(ptr, o, n) \ -({ \ - __typeof__(*(ptr)) _o_ = (o); \ - __typeof__(*(ptr)) _n_ = (n); \ - (__typeof__(*(ptr))) __cmpxchg((ptr), \ - _o_, _n_, sizeof(*(ptr))); \ -}) + _arch_cmpxchg((ptr), (o), (n), ".rl", "", " fence rw, rw\n") #define arch_cmpxchg_local(ptr, o, n) \ - (__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr)))) + arch_cmpxchg_relaxed((ptr), (o), (n)) #define arch_cmpxchg64(ptr, o, n) \ ({ \