On Thu, Aug 01, 2024 at 10:50:58AM +0100, Alan Maguire wrote:
> For kernel builds, pahole is called with -j to specify multithreading
> as long as it is >= 1.22. However, if elfutils are older than 0.178
> at compile time, multithreading is not supported and we emit a
> warning to stderr. The problem is this message will be emitted each
> time pahole is run, and this translates to thousands of times in a
> kernel build (once for vmlinux and once for each module). Often users
> who are not familiar with BTF generation or pahole reasonably assume
> this is an error, whereas it is actually fine; it just means that
> pahole is a bit slower to generate BTF.
>
> Move the message to verbose mode only, as in debugging cases it is
> important to know if pahole is running in parallel.
Thanks, applied to tmp.perf-tools-next,
- Arnaldo
> Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
> ---
> pahole.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/pahole.c b/pahole.c
> index dd5002a..4db5107 100644
> --- a/pahole.c
> +++ b/pahole.c
> @@ -1889,7 +1889,8 @@ static error_t pahole__options_parser(int key, char *arg,
> conf_load.nr_jobs = arg ? atoi(arg) :
> sysconf(_SC_NPROCESSORS_ONLN) * 1.1;
> #else
> - fputs("pahole: Multithreading requires elfutils >= 0.178. Continuing with a single thread...\n", stderr);
> + if (global_verbose)
> + fputs("pahole: Multithreading requires elfutils >= 0.178. Continuing with a single thread...\n", stderr);
> #endif
> break;
> case ARGP_btf_encode_detached:
> --
> 2.43.5
