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| author | Jakub Kicinski <kuba@kernel.org> | 2026-01-25 13:14:14 -0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-01-25 13:14:15 -0800 |
| commit | 3f7522f36b5f1e4e061ee076cfe74a3af7eaa75b (patch) | |
| tree | ae5c98af46521fe37d038e67725932846152fc60 /include/linux | |
| parent | 3085ff59fec593ae1135608edd8afdf0e5889cad (diff) | |
| parent | 58d4ca5b69947c9d8ee197095e6c1c3b5c078716 (diff) | |
Merge branch 'u64_stats-introduce-u64_stats_copy'
David Yang says:
====================
u64_stats: Introduce u64_stats_copy()
On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. memcpy() should not be considered atomic
against u64 values. Use u64_stats_copy() instead.
====================
Link: https://patch.msgid.link/20260120092137.2161162-1-mmyangfl@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/u64_stats_sync.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/u64_stats_sync.h b/include/linux/u64_stats_sync.h index 457879938fc1..849ff6e159c6 100644 --- a/include/linux/u64_stats_sync.h +++ b/include/linux/u64_stats_sync.h @@ -79,6 +79,14 @@ static inline u64 u64_stats_read(const u64_stats_t *p) return local64_read(&p->v); } +static inline void *u64_stats_copy(void *dst, const void *src, size_t len) +{ + BUILD_BUG_ON(len % sizeof(u64_stats_t)); + for (size_t i = 0; i < len / sizeof(u64_stats_t); i++) + ((u64 *)dst)[i] = local64_read(&((local64_t *)src)[i]); + return dst; +} + static inline void u64_stats_set(u64_stats_t *p, u64 val) { local64_set(&p->v, val); @@ -110,6 +118,7 @@ static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp, } #else /* 64 bit */ +#include <linux/string.h> typedef struct { u64 v; @@ -120,6 +129,12 @@ static inline u64 u64_stats_read(const u64_stats_t *p) return p->v; } +static inline void *u64_stats_copy(void *dst, const void *src, size_t len) +{ + BUILD_BUG_ON(len % sizeof(u64_stats_t)); + return memcpy(dst, src, len); +} + static inline void u64_stats_set(u64_stats_t *p, u64 val) { p->v = val; |