include/host: Split out atomic128-cas.h

Separates the aarch64-specific portion into its own file.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2023-05-18 08:22:51 -07:00
parent 0dd0c7fa20
commit 412db3d5b5
3 changed files with 87 additions and 54 deletions

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@ -0,0 +1,43 @@
/*
* SPDX-License-Identifier: GPL-2.0-or-later
* Compare-and-swap for 128-bit atomic operations, AArch64 version.
*
* Copyright (C) 2018, 2023 Linaro, Ltd.
*
* See docs/devel/atomics.rst for discussion about the guarantees each
* atomic primitive is meant to provide.
*/
#ifndef AARCH64_ATOMIC128_CAS_H
#define AARCH64_ATOMIC128_CAS_H
/* Through gcc 10, aarch64 has no support for 128-bit atomics. */
#if defined(CONFIG_ATOMIC128) || defined(CONFIG_CMPXCHG128)
#include "host/include/generic/host/atomic128-cas.h"
#else
static inline Int128 atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new)
{
uint64_t cmpl = int128_getlo(cmp), cmph = int128_gethi(cmp);
uint64_t newl = int128_getlo(new), newh = int128_gethi(new);
uint64_t oldl, oldh;
uint32_t tmp;
asm("0: ldaxp %[oldl], %[oldh], %[mem]\n\t"
"cmp %[oldl], %[cmpl]\n\t"
"ccmp %[oldh], %[cmph], #0, eq\n\t"
"b.ne 1f\n\t"
"stlxp %w[tmp], %[newl], %[newh], %[mem]\n\t"
"cbnz %w[tmp], 0b\n"
"1:"
: [mem] "+m"(*ptr), [tmp] "=&r"(tmp),
[oldl] "=&r"(oldl), [oldh] "=&r"(oldh)
: [cmpl] "r"(cmpl), [cmph] "r"(cmph),
[newl] "r"(newl), [newh] "r"(newh)
: "memory", "cc");
return int128_make128(oldl, oldh);
}
# define HAVE_CMPXCHG128 1
#endif
#endif /* AARCH64_ATOMIC128_CAS_H */

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/*
* SPDX-License-Identifier: GPL-2.0-or-later
* Compare-and-swap for 128-bit atomic operations, generic version.
*
* Copyright (C) 2018, 2023 Linaro, Ltd.
*
* See docs/devel/atomics.rst for discussion about the guarantees each
* atomic primitive is meant to provide.
*/
#ifndef HOST_ATOMIC128_CAS_H
#define HOST_ATOMIC128_CAS_H
#if defined(CONFIG_ATOMIC128)
static inline Int128 atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new)
{
Int128Alias r, c, n;
c.s = cmp;
n.s = new;
r.i = qatomic_cmpxchg__nocheck((__int128_t *)ptr, c.i, n.i);
return r.s;
}
# define HAVE_CMPXCHG128 1
#elif defined(CONFIG_CMPXCHG128)
static inline Int128 atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new)
{
Int128Alias r, c, n;
c.s = cmp;
n.s = new;
r.i = __sync_val_compare_and_swap_16((__int128_t *)ptr, c.i, n.i);
return r.s;
}
# define HAVE_CMPXCHG128 1
#else
/* Fallback definition that must be optimized away, or error. */
Int128 QEMU_ERROR("unsupported atomic")
atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new);
# define HAVE_CMPXCHG128 0
#endif
#endif /* HOST_ATOMIC128_CAS_H */

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@ -41,60 +41,7 @@
* Therefore, special case each platform.
*/
#if defined(CONFIG_ATOMIC128)
static inline Int128 atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new)
{
Int128Alias r, c, n;
c.s = cmp;
n.s = new;
r.i = qatomic_cmpxchg__nocheck((__int128_t *)ptr, c.i, n.i);
return r.s;
}
# define HAVE_CMPXCHG128 1
#elif defined(CONFIG_CMPXCHG128)
static inline Int128 atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new)
{
Int128Alias r, c, n;
c.s = cmp;
n.s = new;
r.i = __sync_val_compare_and_swap_16((__int128_t *)ptr, c.i, n.i);
return r.s;
}
# define HAVE_CMPXCHG128 1
#elif defined(__aarch64__)
/* Through gcc 8, aarch64 has no support for 128-bit at all. */
static inline Int128 atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new)
{
uint64_t cmpl = int128_getlo(cmp), cmph = int128_gethi(cmp);
uint64_t newl = int128_getlo(new), newh = int128_gethi(new);
uint64_t oldl, oldh;
uint32_t tmp;
asm("0: ldaxp %[oldl], %[oldh], %[mem]\n\t"
"cmp %[oldl], %[cmpl]\n\t"
"ccmp %[oldh], %[cmph], #0, eq\n\t"
"b.ne 1f\n\t"
"stlxp %w[tmp], %[newl], %[newh], %[mem]\n\t"
"cbnz %w[tmp], 0b\n"
"1:"
: [mem] "+m"(*ptr), [tmp] "=&r"(tmp),
[oldl] "=&r"(oldl), [oldh] "=&r"(oldh)
: [cmpl] "r"(cmpl), [cmph] "r"(cmph),
[newl] "r"(newl), [newh] "r"(newh)
: "memory", "cc");
return int128_make128(oldl, oldh);
}
# define HAVE_CMPXCHG128 1
#else
/* Fallback definition that must be optimized away, or error. */
Int128 QEMU_ERROR("unsupported atomic")
atomic16_cmpxchg(Int128 *ptr, Int128 cmp, Int128 new);
# define HAVE_CMPXCHG128 0
#endif /* Some definition for HAVE_CMPXCHG128 */
#include "host/atomic128-cas.h"
#if defined(CONFIG_ATOMIC128)
static inline Int128 atomic16_read(Int128 *ptr)