From 1bf7d836e57ba4943e33e163e730cd77ab837572 Mon Sep 17 00:00:00 2001 From: Martin Liška Date: Fri, 12 Aug 2022 13:40:49 +0200 Subject: perf record: Improve error message of -p not_existing_pid MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When one uses -p $not_existing_pid, the output of --help is printed: $ perf record -p 123456789 2>&1 | head -n3 Usage: perf record [] [] or: perf record [] -- [] Let's change it something similar what perf top -p $not_existing_pid prints: $ ./perf top -p 123456789 --stdio Error: Couldn't create thread/CPU maps: No such process Newly suggested error message: $ ./perf record -p 123456789 Couldn't create thread/CPU maps: No such process Signed-off-by: Martin Liška Tested-by: Arnaldo Carvalho de Melo Link: http://lore.kernel.org/lkml/8e00eda1-4de0-2c44-ce67-d4df48ac1f7c@suse.cz Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'tools/perf') diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index cf5c5379ceaa..4713f0f3a6cf 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -3996,8 +3996,15 @@ int cmd_record(int argc, const char **argv) arch__add_leaf_frame_record_opts(&rec->opts); err = -ENOMEM; - if (evlist__create_maps(rec->evlist, &rec->opts.target) < 0) - usage_with_options(record_usage, record_options); + if (evlist__create_maps(rec->evlist, &rec->opts.target) < 0) { + if (rec->opts.target.pid != NULL) { + pr_err("Couldn't create thread/CPU maps: %s\n", + errno == ENOENT ? "No such process" : str_error_r(errno, errbuf, sizeof(errbuf))); + goto out; + } + else + usage_with_options(record_usage, record_options); + } err = auxtrace_record__options(rec->itr, rec->evlist, &rec->opts); if (err) -- cgit v1.2.3