diff options
| author | Eric Dumazet <edumazet@google.com> | 2021-10-26 14:41:33 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-08 19:12:40 +0100 |
| commit | aa5040691cb761a04c206a893e5771a904d22ab7 (patch) | |
| tree | 1a1fa47a2dfcb1f13bd113de2f6a39c45d865198 /include | |
| parent | 82a82ad92746e8672c6212fc0f94e02cae1885d2 (diff) | |
bpf: Use u64_stats_t in struct bpf_prog_stats
[ Upstream commit 61a0abaee2092eee69e44fe60336aa2f5b578938 ]
Commit 316580b69d0a ("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>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/filter.h | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 1611dc9d4420..a9956b681f09 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -554,9 +554,9 @@ struct bpf_binary_header { }; struct bpf_prog_stats { - u64 cnt; - u64 nsecs; - u64 misses; + u64_stats_t cnt; + u64_stats_t nsecs; + u64_stats_t misses; struct u64_stats_sync syncp; } __aligned(2 * sizeof(u64)); @@ -618,8 +618,8 @@ static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog, ret = dfunc(ctx, prog->insnsi, prog->bpf_func); stats = this_cpu_ptr(prog->stats); flags = u64_stats_update_begin_irqsave(&stats->syncp); - stats->cnt++; - stats->nsecs += sched_clock() - start; + u64_stats_inc(&stats->cnt); + u64_stats_add(&stats->nsecs, sched_clock() - start); u64_stats_update_end_irqrestore(&stats->syncp, flags); } else { ret = dfunc(ctx, prog->insnsi, prog->bpf_func); |