From: Namhyung Kim namhyung@kernel.org
[ Upstream commit 2d656b0f81b22101db0447f890e39fdd736b745e ]
When --for-each-cgroup option is used, it fails when any of events is not supported and exits immediately. This is not how 'perf stat' handles unsupported events.
Let's ignore the failure and proceed with others so that the output is similar to when BPF counters are not used:
Before:
$ sudo ./perf stat -a --bpf-counters -e L1-icache-loads,L1-dcache-loads --for-each-cgroup system.slice,user.slice sleep 1 Failed to open first cgroup events $
After it shows output similat to when --bpf-counters isn't specified:
$ sudo ./perf stat -a --bpf-counters -e L1-icache-loads,L1-dcache-loads --for-each-cgroup system.slice,user.slice sleep 1
Performance counter stats for 'system wide':
<not supported> L1-icache-loads system.slice 29,892,418 L1-dcache-loads system.slice <not supported> L1-icache-loads user.slice 52,497,220 L1-dcache-loads user.slice $
Fixes: 944138f048f7d759 ("perf stat: Enable BPF counter with --for-each-cgroup") Signed-off-by: Namhyung Kim namhyung@kernel.org Tested-by: Arnaldo Carvalho de Melo acme@redhat.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Ian Rogers irogers@google.com Cc: Ingo Molnar mingo@kernel.org Cc: Jiri Olsa jolsa@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Song Liu songliubraving@fb.com Link: https://lore.kernel.org/r/20230104064402.1551516-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/bpf_counter_cgroup.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-)
diff --git a/tools/perf/util/bpf_counter_cgroup.c b/tools/perf/util/bpf_counter_cgroup.c index 3c2df7522f6f..1c82377ed78b 100644 --- a/tools/perf/util/bpf_counter_cgroup.c +++ b/tools/perf/util/bpf_counter_cgroup.c @@ -116,27 +116,19 @@ static int bperf_load_program(struct evlist *evlist)
/* open single copy of the events w/o cgroup */ err = evsel__open_per_cpu(evsel, evsel->core.cpus, -1); - if (err) { - pr_err("Failed to open first cgroup events\n"); - goto out; - } + if (err == 0) + evsel->supported = true;
map_fd = bpf_map__fd(skel->maps.events); perf_cpu_map__for_each_cpu(cpu, j, evsel->core.cpus) { int fd = FD(evsel, j); __u32 idx = evsel->core.idx * total_cpus + cpu.cpu;
- err = bpf_map_update_elem(map_fd, &idx, &fd, - BPF_ANY); - if (err < 0) { - pr_err("Failed to update perf_event fd\n"); - goto out; - } + bpf_map_update_elem(map_fd, &idx, &fd, BPF_ANY); }
evsel->cgrp = leader_cgrp; } - evsel->supported = true;
if (evsel->cgrp == cgrp) continue;