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riscv/cmpxchg: Deduplicate xchg() asm functions

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In this header every xchg 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_xchg* generation.

(This did not cause any change in generated asm)

Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
Tested-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20240103163203.72768-3-leobras@redhat.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Leonardo Bras
2024-01-03 13:31:59 -03:00
committed by Palmer Dabbelt
parent 6613476e22
commit 4bfa185fe3
1 changed files with 24 additions and 116 deletions
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arch/riscv/include/asm/cmpxchg.h
+24 -116
View File
@@ -11,140 +11,48 @@
#include <asm/barrier.h>
#include <asm/fence.h>
#define __xchg_relaxed(ptr, new, size) \
#define __arch_xchg(sfx, prepend, append, r, p, n) \
({ \
__asm__ __volatile__ ( \
prepend \
" amoswap" sfx " %0, %2, %1\n" \
append \
: "=r" (r), "+A" (*(p)) \
: "r" (n) \
: "memory"); \
})
#define _arch_xchg(ptr, new, sfx, prepend, append) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
__typeof__(*(__ptr)) __new = (new); \
__typeof__(*(__ptr)) __ret; \
switch (sizeof(*__ptr)) { \
case 4: \
__asm__ __volatile__ ( \
" amoswap.w %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
__arch_xchg(".w" sfx, prepend, append, \
__ret, __ptr, __new); \
break; \
case 8: \
__asm__ __volatile__ ( \
" amoswap.d %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
__arch_xchg(".d" sfx, prepend, append, \
__ret, __ptr, __new); \
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
(__typeof__(*(__ptr)))__ret; \
})
#define arch_xchg_relaxed(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_relaxed((ptr), \
_x_, sizeof(*(ptr))); \
})
#define __xchg_acquire(ptr, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
" amoswap.w %0, %2, %1\n" \
RISCV_ACQUIRE_BARRIER \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__ ( \
" amoswap.d %0, %2, %1\n" \
RISCV_ACQUIRE_BARRIER \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
})
_arch_xchg(ptr, x, "", "", "")
#define arch_xchg_acquire(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_acquire((ptr), \
_x_, sizeof(*(ptr))); \
})
#define __xchg_release(ptr, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
RISCV_RELEASE_BARRIER \
" amoswap.w %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__ ( \
RISCV_RELEASE_BARRIER \
" amoswap.d %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
})
_arch_xchg(ptr, x, "", "", RISCV_ACQUIRE_BARRIER)
#define arch_xchg_release(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_release((ptr), \
_x_, sizeof(*(ptr))); \
})
#define __arch_xchg(ptr, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
" amoswap.w.aqrl %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__ ( \
" amoswap.d.aqrl %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
})
_arch_xchg(ptr, x, "", RISCV_RELEASE_BARRIER, "")
#define arch_xchg(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __arch_xchg((ptr), _x_, sizeof(*(ptr))); \
})
_arch_xchg(ptr, x, ".aqrl", "", "")
#define xchg32(ptr, x) \
({ \