Guo Ren 186f69b64c csky: atomic: Optimize cmpxchg with acquire & release ... Optimize cmpxchg with ASM acquire/release fence ASM instructions instead of previous generic based. Prevent a fence when cmxchg's first load != old. Comments by Rutland: 8e86f0b409 ("arm64: atomics: fix use of acquire + release for full barrier semantics") Comments by Boqun: FWIW, you probably need to make sure that a barrier instruction inside an lr/sc loop is a good thing. IIUC, the execution time of a barrier instruction is determined by the status of store buffers and invalidate queues (and probably other stuffs), so it may increase the execution time of the lr/sc loop, and make it unlikely to succeed. But this really depends on how the arch executes these instructions. Link: https://lore.kernel.org/linux-riscv/CAJF2gTSAxpAi=LbAdu7jntZRUa=-dJwL0VfmDfBV5MHB=rcZ-w@mail.gmail.com/T/#m27a0f1342995deae49ce1d0e1f2683f8a181d6c3 Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com>		2022-04-25 13:51:42 +08:00
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abiv1	csky: Add C based string functions	2022-04-18 21:23:55 +08:00
abiv2	csky: Add C based string functions	2022-04-18 21:23:55 +08:00
boot	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
configs	csky: Minimize defconfig to support buildroot config.fragment	2020-02-21 15:43:25 +08:00
include	csky: atomic: Optimize cmpxchg with acquire & release	2022-04-25 13:51:42 +08:00
kernel	csky: optimize memcpy_{from,to}io() and memset_io()	2022-04-18 21:23:55 +08:00
lib	csky: Add C based string functions	2022-04-18 21:23:55 +08:00
mm	csky: Fix versioncheck warnings	2022-04-08 15:05:23 +08:00
Kbuild	kbuild: use more subdir- for visiting subdirectories while cleaning	2021-10-24 13:49:46 +09:00
Kconfig	csky: Add C based string functions	2022-04-18 21:23:55 +08:00
Kconfig.debug	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Kconfig.platforms	csky/Kconfig: Add Kconfig.platforms to support some drivers	2020-02-21 15:43:24 +08:00
Makefile	kbuild: use more subdir- for visiting subdirectories while cleaning	2021-10-24 13:49:46 +09:00