From: Namhyung Kim <namhyung@kernel.org> mainline inclusion from mainline-v5.13-rc4 commit c673b7f59e940061467200f1746820a178444bd0 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/ICDP8O Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- It seems the bpf_program__attach() returns a negative error code instead of a NULL pointer in case of error. Fixes: 7fac83aaf2ee ("perf stat: Introduce 'bperf' to share hardware PMCs with BPF") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Link: http://lore.kernel.org/lkml/20210527220052.1657578-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Xiaomeng Zhang <zhangxiaomeng13@huawei.com> --- tools/perf/util/bpf_counter.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c index f3f6ff428fdb..0a4477d493aa 100644 --- a/tools/perf/util/bpf_counter.c +++ b/tools/perf/util/bpf_counter.c @@ -401,10 +401,10 @@ static int bperf_reload_leader_program(struct evsel *evsel, int attr_map_fd, goto out; } - err = -1; link = bpf_program__attach(skel->progs.on_switch); - if (!link) { + if (IS_ERR(link)) { pr_err("Failed to attach leader program\n"); + err = PTR_ERR(link); goto out; } -- 2.34.1