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x86/percpu: Define {raw,this}_cpu_try_cmpxchg{64,128}

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Define target-specific {raw,this}_cpu_try_cmpxchg64() and
{raw,this}_cpu_try_cmpxchg128() macros. These definitions override
the generic fallback definitions and enable target-specific
optimized implementations.

Several places in mm/slub.o improve from e.g.:

    53bc:	48 8d 4f 40          	lea    0x40(%rdi),%rcx
    53c0:	48 89 fa             	mov    %rdi,%rdx
    53c3:	49 8b 5c 05 00       	mov    0x0(%r13,%rax,1),%rbx
    53c8:	4c 89 e8             	mov    %r13,%rax
    53cb:	49 8d 30             	lea    (%r8),%rsi
    53ce:	e8 00 00 00 00       	call   53d3 <...>
			53cf: R_X86_64_PLT32	this_cpu_cmpxchg16b_emu-0x4
    53d3:	48 31 d7             	xor    %rdx,%rdi
    53d6:	4c 31 e8             	xor    %r13,%rax
    53d9:	48 09 c7             	or     %rax,%rdi
    53dc:	75 ae                	jne    538c <...>

to:

    53bc:	48 8d 4a 40          	lea    0x40(%rdx),%rcx
    53c0:	49 8b 1c 07          	mov    (%r15,%rax,1),%rbx
    53c4:	4c 89 f8             	mov    %r15,%rax
    53c7:	48 8d 37             	lea    (%rdi),%rsi
    53ca:	e8 00 00 00 00       	call   53cf <...>
			53cb: R_X86_64_PLT32	this_cpu_cmpxchg16b_emu-0x4
    53cf:	75 bb                	jne    538c <...>

reducing the size of mm/slub.o by 80 bytes:

   text    data     bss     dec     hex filename
  39758    5337    4208   49303    c097 slub-new.o
  39838    5337    4208   49383    c0e7 slub-old.o

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230906185941.53527-1-ubizjak@gmail.com
This commit is contained in:
Uros Bizjak 2023-09-06 20:58:44 +02:00 committed by Ingo Molnar
parent 3dae5c43ba
commit 54cd971c6f
1 changed files with 67 additions and 0 deletions
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67
arch/x86/include/asm/percpu.h
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@ -237,12 +237,47 @@ do { \
#define raw_cpu_cmpxchg64(pcp, oval, nval) percpu_cmpxchg64_op(8, , pcp, oval, nval)
#define this_cpu_cmpxchg64(pcp, oval, nval) percpu_cmpxchg64_op(8, volatile, pcp, oval, nval)
#define percpu_try_cmpxchg64_op(size, qual, _var, _ovalp, _nval) \
({ \
bool success; \
u64 *_oval = (u64 *)(_ovalp); \
union { \
u64 var; \
struct { \
u32 low, high; \
}; \
} old__, new__; \
\
old__.var = *_oval; \
new__.var = _nval; \
\
asm qual (ALTERNATIVE("leal %P[var], %%esi; call this_cpu_cmpxchg8b_emu", \
"cmpxchg8b " __percpu_arg([var]), X86_FEATURE_CX8) \
CC_SET(z) \
: CC_OUT(z) (success), \
[var] "+m" (_var), \
"+a" (old__.low), \
"+d" (old__.high) \
: "b" (new__.low), \
"c" (new__.high) \
: "memory", "esi"); \
if (unlikely(!success)) \
*_oval = old__.var; \
likely(success); \
})
#define raw_cpu_try_cmpxchg64(pcp, ovalp, nval) percpu_try_cmpxchg64_op(8, , pcp, ovalp, nval)
#define this_cpu_try_cmpxchg64(pcp, ovalp, nval) percpu_try_cmpxchg64_op(8, volatile, pcp, ovalp, nval)
#endif
#ifdef CONFIG_X86_64
#define raw_cpu_cmpxchg64(pcp, oval, nval) percpu_cmpxchg_op(8, , pcp, oval, nval);
#define this_cpu_cmpxchg64(pcp, oval, nval) percpu_cmpxchg_op(8, volatile, pcp, oval, nval);
#define raw_cpu_try_cmpxchg64(pcp, ovalp, nval) percpu_try_cmpxchg_op(8, , pcp, ovalp, nval);
#define this_cpu_try_cmpxchg64(pcp, ovalp, nval) percpu_try_cmpxchg_op(8, volatile, pcp, ovalp, nval);
#define percpu_cmpxchg128_op(size, qual, _var, _oval, _nval) \
({ \
union { \
@ -269,6 +304,38 @@ do { \
#define raw_cpu_cmpxchg128(pcp, oval, nval) percpu_cmpxchg128_op(16, , pcp, oval, nval)
#define this_cpu_cmpxchg128(pcp, oval, nval) percpu_cmpxchg128_op(16, volatile, pcp, oval, nval)
#define percpu_try_cmpxchg128_op(size, qual, _var, _ovalp, _nval) \
({ \
bool success; \
u128 *_oval = (u128 *)(_ovalp); \
union { \
u128 var; \
struct { \
u64 low, high; \
}; \
} old__, new__; \
\
old__.var = *_oval; \
new__.var = _nval; \
\
asm qual (ALTERNATIVE("leaq %P[var], %%rsi; call this_cpu_cmpxchg16b_emu", \
"cmpxchg16b " __percpu_arg([var]), X86_FEATURE_CX16) \
CC_SET(z) \
: CC_OUT(z) (success), \
[var] "+m" (_var), \
"+a" (old__.low), \
"+d" (old__.high) \
: "b" (new__.low), \
"c" (new__.high) \
: "memory", "rsi"); \
if (unlikely(!success)) \
*_oval = old__.var; \
likely(success); \
})
#define raw_cpu_try_cmpxchg128(pcp, ovalp, nval) percpu_try_cmpxchg128_op(16, , pcp, ovalp, nval)
#define this_cpu_try_cmpxchg128(pcp, ovalp, nval) percpu_try_cmpxchg128_op(16, volatile, pcp, ovalp, nval)
#endif
/*