diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2016-06-28 12:18:24 +0200 |
|---|---|---|
| committer | Michael Bestas <mkbestas@lineageos.org> | 2022-04-19 00:51:45 +0300 |
| commit | d07f0b4132a0bd1dff3a21863ad81279620693fc (patch) | |
| tree | 5b2662ea942fb47c28a0a80c91574cc9f1ea130e /kernel | |
| parent | fc6c6256bb108dde5c7f533d6dda2e9044a7283c (diff) | |
bpf, trace: fetch current cpu only once
We currently have two invocations, which is unnecessary. Fetch it only
once and use the smp_processor_id() variant, so we also get preemption
checks along with it when DEBUG_PREEMPT is set.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index de4af0208f61..c95bf2a845f6 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -296,13 +296,14 @@ __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map, u64 flags, struct perf_raw_record *raw) { struct bpf_array *array = container_of(map, struct bpf_array, map); + unsigned int cpu = smp_processor_id(); u64 index = flags & BPF_F_INDEX_MASK; struct perf_sample_data sample_data; struct bpf_event_entry *ee; struct perf_event *event; if (index == BPF_F_CURRENT_CPU) - index = raw_smp_processor_id(); + index = cpu; if (unlikely(index >= array->map.max_entries)) return -E2BIG; @@ -315,7 +316,7 @@ __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map, event->attr.config != PERF_COUNT_SW_BPF_OUTPUT)) return -EINVAL; - if (unlikely(event->oncpu != smp_processor_id())) + if (unlikely(event->oncpu != cpu)) return -EOPNOTSUPP; perf_sample_data_init(&sample_data, 0, 0); |