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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/include/asm/cmpxchg_64.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/cmpxchg_64.h')
-rw-r--r--arch/x86/include/asm/cmpxchg_64.h90
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cmpxchg_64.h b/arch/x86/include/asm/cmpxchg_64.h
new file mode 100644
index 0000000000..44b08b53ab
--- /dev/null
+++ b/arch/x86/include/asm/cmpxchg_64.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_CMPXCHG_64_H
+#define _ASM_X86_CMPXCHG_64_H
+
+#define arch_cmpxchg64(ptr, o, n) \
+({ \
+ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
+ arch_cmpxchg((ptr), (o), (n)); \
+})
+
+#define arch_cmpxchg64_local(ptr, o, n) \
+({ \
+ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
+ arch_cmpxchg_local((ptr), (o), (n)); \
+})
+
+#define arch_try_cmpxchg64(ptr, po, n) \
+({ \
+ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
+ arch_try_cmpxchg((ptr), (po), (n)); \
+})
+
+union __u128_halves {
+ u128 full;
+ struct {
+ u64 low, high;
+ };
+};
+
+#define __arch_cmpxchg128(_ptr, _old, _new, _lock) \
+({ \
+ union __u128_halves o = { .full = (_old), }, \
+ n = { .full = (_new), }; \
+ \
+ asm volatile(_lock "cmpxchg16b %[ptr]" \
+ : [ptr] "+m" (*(_ptr)), \
+ "+a" (o.low), "+d" (o.high) \
+ : "b" (n.low), "c" (n.high) \
+ : "memory"); \
+ \
+ o.full; \
+})
+
+static __always_inline u128 arch_cmpxchg128(volatile u128 *ptr, u128 old, u128 new)
+{
+ return __arch_cmpxchg128(ptr, old, new, LOCK_PREFIX);
+}
+#define arch_cmpxchg128 arch_cmpxchg128
+
+static __always_inline u128 arch_cmpxchg128_local(volatile u128 *ptr, u128 old, u128 new)
+{
+ return __arch_cmpxchg128(ptr, old, new,);
+}
+#define arch_cmpxchg128_local arch_cmpxchg128_local
+
+#define __arch_try_cmpxchg128(_ptr, _oldp, _new, _lock) \
+({ \
+ union __u128_halves o = { .full = *(_oldp), }, \
+ n = { .full = (_new), }; \
+ bool ret; \
+ \
+ asm volatile(_lock "cmpxchg16b %[ptr]" \
+ CC_SET(e) \
+ : CC_OUT(e) (ret), \
+ [ptr] "+m" (*ptr), \
+ "+a" (o.low), "+d" (o.high) \
+ : "b" (n.low), "c" (n.high) \
+ : "memory"); \
+ \
+ if (unlikely(!ret)) \
+ *(_oldp) = o.full; \
+ \
+ likely(ret); \
+})
+
+static __always_inline bool arch_try_cmpxchg128(volatile u128 *ptr, u128 *oldp, u128 new)
+{
+ return __arch_try_cmpxchg128(ptr, oldp, new, LOCK_PREFIX);
+}
+#define arch_try_cmpxchg128 arch_try_cmpxchg128
+
+static __always_inline bool arch_try_cmpxchg128_local(volatile u128 *ptr, u128 *oldp, u128 new)
+{
+ return __arch_try_cmpxchg128(ptr, oldp, new,);
+}
+#define arch_try_cmpxchg128_local arch_try_cmpxchg128_local
+
+#define system_has_cmpxchg128() boot_cpu_has(X86_FEATURE_CX16)
+
+#endif /* _ASM_X86_CMPXCHG_64_H */