From 2c369d91d0933aaff96b6b807b22363e6a38a625 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Fri, 22 Aug 2025 17:00:24 -0700 Subject: perf symbol: Add blocking argument to filename__read_build_id When synthesizing build-ids, for build ID mmap2 events, they will be added for data mmaps if -d/--data is specified. The files opened for their build IDs may block on the open causing perf to hang during synthesis. There is some robustness in existing calls to filename__read_build_id by checking the file path is to a regular file, which unfortunately fails for symlinks. Rather than adding more is_regular_file calls, switch filename__read_build_id to take a "block" argument and specify O_NONBLOCK when this is false. The existing is_regular_file checking callers and the event synthesis callers are made to pass false and thereby avoiding the hang. Fixes: 53b00ff358dc ("perf record: Make --buildid-mmap the default") Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250823000024.724394-3-irogers@google.com Signed-off-by: Namhyung Kim --- tools/perf/builtin-inject.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'tools/perf/builtin-inject.c') diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c index 40ba6a94f719..a114b3fa1bea 100644 --- a/tools/perf/builtin-inject.c +++ b/tools/perf/builtin-inject.c @@ -680,12 +680,12 @@ static int dso__read_build_id(struct dso *dso) mutex_lock(dso__lock(dso)); nsinfo__mountns_enter(dso__nsinfo(dso), &nsc); - if (filename__read_build_id(dso__long_name(dso), &bid) > 0) + if (filename__read_build_id(dso__long_name(dso), &bid, /*block=*/true) > 0) dso__set_build_id(dso, &bid); else if (dso__nsinfo(dso)) { char *new_name = dso__filename_with_chroot(dso, dso__long_name(dso)); - if (new_name && filename__read_build_id(new_name, &bid) > 0) + if (new_name && filename__read_build_id(new_name, &bid, /*block=*/true) > 0) dso__set_build_id(dso, &bid); free(new_name); } -- cgit v1.2.3