kernel/linux.git/arch/mips/include/asm/atomic.h, branch v5.10.258

MIPS: locking/atomic: Fix atomic{_64,}_sub_if_positive

2023-06-14T09:10:00+00:00

commit cb95ea79b3fc772c5873a7a4532ab4c14a455da2 upstream. This looks like a typo and that caused atomic64 test failed. Signed-off-by: Rui Wang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

MIPS: Compare __SYNC_loongson3_war against 0

2021-03-04T10:37:41+00:00

[ Upstream commit 8790ccf8daf1a8c53b6cb8ce0c9a109274bd3fa8 ] When building with clang when CONFIG_CPU_LOONGSON3_WORKAROUNDS is enabled: In file included from lib/errseq.c:4: In file included from ./include/linux/atomic.h:7: ./arch/mips/include/asm/atomic.h:52:1: warning: converting the result of '<<' to a boolean always evaluates to true [-Wtautological-constant-compare] ATOMIC_OPS(atomic64, s64) ^ ./arch/mips/include/asm/atomic.h:40:9: note: expanded from macro 'ATOMIC_OPS' return cmpxchg(&v->counter, o, n); ^ ./arch/mips/include/asm/cmpxchg.h:194:7: note: expanded from macro 'cmpxchg' if (!__SYNC_loongson3_war) ^ ./arch/mips/include/asm/sync.h:147:34: note: expanded from macro '__SYNC_loongson3_war' # define __SYNC_loongson3_war (1 << 31) ^ While it is not wrong that the result of this shift is always true in a boolean context, it is not a problem here. Regardless, the warning is really noisy so rather than making the shift a boolean implicitly, use it in an equality comparison so the shift is used as an integer value. Fixes: 4d1dbfe6cbec ("MIPS: atomic: Emit Loongson3 sync workarounds within asm") Fixes: a91f2a1dba44 ("MIPS: cmpxchg: Omit redundant barriers for Loongson3") Reported-by: kernel test robot Signed-off-by: Nathan Chancellor Acked-by: Nick Desaulniers Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

locking/atomic: Move ATOMIC_INIT into linux/types.h

2020-07-29T14:14:18+00:00

This patch moves ATOMIC_INIT from asm/atomic.h into linux/types.h. This allows users of atomic_t to use ATOMIC_INIT without having to include atomic.h as that way may lead to header loops. Signed-off-by: Herbert Xu Signed-off-by: Peter Zijlstra (Intel) Acked-by: Waiman Long Link: https://lkml.kernel.org/r/20200729123105.GB7047@gondor.apana.org.au

MIPS: atomic: Deduplicate 32b & 64b read, set, xchg, cmpxchg

2019-10-07T16:42:36+00:00

Remove the remaining duplication between 32b & 64b in asm/atomic.h by making use of an ATOMIC_OPS() macro to generate: - atomic_read()/atomic64_read() - atomic_set()/atomic64_set() - atomic_cmpxchg()/atomic64_cmpxchg() - atomic_xchg()/atomic64_xchg() This is consistent with the way all other functions in asm/atomic.h are generated, and ensures consistency between the 32b & 64b functions. Of note is that this results in the above now being static inline functions rather than macros. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org

MIPS: atomic: Unify 32b & 64b sub_if_positive

2019-10-07T16:42:34+00:00

Unify the definitions of atomic_sub_if_positive() & atomic64_sub_if_positive() using a macro like we do for most other atomic functions. This allows us to share the implementation ensuring consistency between the two. Notably this provides the appropriate loongson3_war barriers in the atomic64_sub_if_positive() case which were previously missing. The code is rearranged a little to handle the !kernel_uses_llsc case first in order to de-indent the LL/SC case & allow us not to go over 80 characters per line. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org

MIPS: atomic: Use _atomic barriers in atomic_sub_if_positive()

2019-10-07T16:42:32+00:00

Use smp_mb__before_atomic() & smp_mb__after_atomic() in atomic_sub_if_positive() rather than the equivalent smp_mb__before_llsc() & smp_llsc_mb(). The former are more standard & this preps us for avoiding redundant duplicate barriers on Loongson3 in a later patch. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org

MIPS: atomic: Emit Loongson3 sync workarounds within asm

2019-10-07T16:42:31+00:00

Generate the sync instructions required to workaround Loongson3 LL/SC errata within inline asm blocks, which feels a little safer than doing it from C where strictly speaking the compiler would be well within its rights to insert a memory access between the separate asm statements we previously had, containing sync & ll instructions respectively. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org

MIPS: atomic: Use one macro to generate 32b & 64b functions

2019-10-07T16:42:29+00:00

Cut down on duplication by generalizing the ATOMIC_OP(), ATOMIC_OP_RETURN() & ATOMIC_FETCH_OP() macros to work for both 32b & 64b atomics, and removing the ATOMIC64_ variants. This ensures consistency between our atomic_* & atomic64_* functions. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org

MIPS: atomic: Handle !kernel_uses_llsc first

2019-10-07T16:42:27+00:00

Handle the !kernel_uses_llsc path first in our ATOMIC_OP(), ATOMIC_OP_RETURN() & ATOMIC_FETCH_OP() macros & return from within the block. This allows us to de-indent the kernel_uses_llsc path by one level which will be useful when making further changes. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org

MIPS: atomic: Fix whitespace in ATOMIC_OP macros

2019-10-07T16:42:26+00:00

We define macros in asm/atomic.h which end each line with space characters before a backslash to continue on the next line. Remove the space characters leaving tabs as the whitespace used for conformity with coding convention. Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: Huacai Chen Cc: Jiaxun Yang Cc: linux-kernel@vger.kernel.org