On 7 Jan 2025, at 2:45 AM, Namhyung Kim [off-list ref] wrote:

Hello,

On Mon, Dec 23, 2024 at 07:26:55PM +0530, Athira Rajeev wrote:

quoted

perf lock contention returns zero exit value even if the lock contention
BPF setup failed.

  # ./perf lock con -b true
  libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled?
  libbpf: failed to find '.BTF' ELF section in /lib/modules/6.13.0-rc3+/build/vmlinux
  libbpf: failed to find valid kernel BTF
  libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled?
  libbpf: failed to find '.BTF' ELF section in /lib/modules/6.13.0-rc3+/build/vmlinux
  libbpf: failed to find valid kernel BTF
  libbpf: Error loading vmlinux BTF: -ESRCH
  libbpf: failed to load object 'lock_contention_bpf'
  libbpf: failed to load BPF skeleton 'lock_contention_bpf': -ESRCH
  Failed to load lock-contention BPF skeleton
  lock contention BPF setup failed
  # echo $?
   0

Fix this by saving the return code for lock_contention_prepare
so that command exits with proper return code

Signed-off-by: Athira Rajeev <redacted>

Thanks for the fix, the change itself looks good but I think we need the
same for setup_output_field() and select_key() as well.

Thanks,
Namhyung

Hi Namhyung

Thanks for reviewing and pointing out setup_output_field() and select_key()
I will send a V2 with handling return code for these two functions as well

Thanks
Athira 

quoted

---
tools/perf/builtin-lock.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 208c482daa56..2226c7dd4ae6 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c

@@ -2049,7 +2049,8 @@ static int 	(int argc, const char **argv)

goto out_delete;
}

- if (lock_contention_prepare(&con) < 0) {
+ err = lock_contention_prepare(&con);
+ if (err < 0) {
pr_err("lock contention BPF setup failed\n");
goto out_delete;
}
-- 
2.43.5