Eric Dumazet aa5040691c bpf: Use u64_stats_t in struct bpf_prog_stats ...

[ Upstream commit 61a0abaee2 ]

Commit 316580b69d ("u64_stats: provide u64_stats_t type")
fixed possible load/store tearing on 64bit arches.

For instance the following C code

stats->nsecs += sched_clock() - start;

Could be rightfully implemented like this by a compiler,
confusing concurrent readers a lot:

stats->nsecs += sched_clock();
// arbitrary delay
stats->nsecs -= start;

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211026214133.3114279-4-eric.dumazet@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

2022-03-08 19:12:40 +01:00

114 KiB

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