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| author | Peter Zijlstra <peterz@infradead.org> | 2023-05-31 15:08:36 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-06-05 09:36:35 +0200 |
| commit | b23e139d0b66c0216e7e9361a5021290395f504c (patch) | |
| tree | 0f4d5c909eab20ea594dda67675d6233923efcf3 /arch/arm64/include/asm/atomic_lse.h | |
| parent | types: Introduce [us]128 (diff) | |
| download | linux-b23e139d0b66c0216e7e9361a5021290395f504c.tar.xz linux-b23e139d0b66c0216e7e9361a5021290395f504c.zip | |
arch: Introduce arch_{,try_}_cmpxchg128{,_local}()
For all architectures that currently support cmpxchg_double()
implement the cmpxchg128() family of functions that is basically the
same but with a saner interface.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20230531132323.452120708@infradead.org
Diffstat (limited to 'arch/arm64/include/asm/atomic_lse.h')
| -rw-r--r-- | arch/arm64/include/asm/atomic_lse.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/atomic_lse.h b/arch/arm64/include/asm/atomic_lse.h index 319958b95cfd..c781281306d0 100644 --- a/arch/arm64/include/asm/atomic_lse.h +++ b/arch/arm64/include/asm/atomic_lse.h @@ -317,4 +317,35 @@ __CMPXCHG_DBL(_mb, al, "memory") #undef __CMPXCHG_DBL +#define __CMPXCHG128(name, mb, cl...) \ +static __always_inline u128 \ +__lse__cmpxchg128##name(volatile u128 *ptr, u128 old, u128 new) \ +{ \ + union __u128_halves r, o = { .full = (old) }, \ + n = { .full = (new) }; \ + register unsigned long x0 asm ("x0") = o.low; \ + register unsigned long x1 asm ("x1") = o.high; \ + register unsigned long x2 asm ("x2") = n.low; \ + register unsigned long x3 asm ("x3") = n.high; \ + register unsigned long x4 asm ("x4") = (unsigned long)ptr; \ + \ + asm volatile( \ + __LSE_PREAMBLE \ + " casp" #mb "\t%[old1], %[old2], %[new1], %[new2], %[v]\n"\ + : [old1] "+&r" (x0), [old2] "+&r" (x1), \ + [v] "+Q" (*(u128 *)ptr) \ + : [new1] "r" (x2), [new2] "r" (x3), [ptr] "r" (x4), \ + [oldval1] "r" (o.low), [oldval2] "r" (o.high) \ + : cl); \ + \ + r.low = x0; r.high = x1; \ + \ + return r.full; \ +} + +__CMPXCHG128( , ) +__CMPXCHG128(_mb, al, "memory") + +#undef __CMPXCHG128 + #endif /* __ASM_ATOMIC_LSE_H */ |