perf bpf: Make bpf__setup_output_event() return the bpf-output event

We're calling it to setup that event, and we'll need it later to decide
if the bpf-output event we're handling is the one setup for a specific
purpose, return it using ERR_PTR, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zhachv7il2n1lopt9aonwhu7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 5 insertions, 4 deletions

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 9b4e24217c46..43a699cfcadf 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -3216,8 +3216,9 @@ int cmd_trace(int argc, const char **argv)
         };
         bool __maybe_unused max_stack_user_set = true;
         bool mmap_pages_user_set = true;
+        struct perf_evsel *evsel;
         const char * const trace_subcommands[] = { "record", NULL };
-        int err;
+        int err = -1;
         char bf[BUFSIZ];
 
         signal(SIGSEGV, sighandler_dump_stack);
@@ -3240,9 +3241,9 @@ int cmd_trace(int argc, const char **argv)
                                        "cgroup monitoring only available in system-wide mode");
         }
 
-        err = bpf__setup_output_event(trace.evlist, "__augmented_syscalls__");
-        if (err) {
-                bpf__strerror_setup_output_event(trace.evlist, err, bf, sizeof(bf));
+        evsel = bpf__setup_output_event(trace.evlist, "__augmented_syscalls__");
+        if (IS_ERR(evsel)) {
+                bpf__strerror_setup_output_event(trace.evlist, PTR_ERR(evsel), bf, sizeof(bf));
                 pr_err("ERROR: Setup trace syscalls enter failed: %s\n", bf);
                 goto out;
         }