diff options
| author | Ian Rogers <irogers@google.com> | 2025-07-24 09:32:48 -0700 |
|---|---|---|
| committer | Namhyung Kim <namhyung@kernel.org> | 2025-07-25 10:37:56 -0700 |
| commit | 53b00ff358dc75b12042b2b2aaf1d0e998fd0075 (patch) | |
| tree | 0949ee937a7c28b64a41140a65f7cf7e13f42b54 /tools/perf/util/synthetic-events.c | |
| parent | 5b11409b924631745eef60a65218ffa496acafd6 (diff) | |
perf record: Make --buildid-mmap the default
Support for build IDs in mmap2 perf events has been present since
Linux v5.12:
https://lore.kernel.org/lkml/20210219194619.1780437-1-acme@kernel.org/
Build ID mmap events don't avoid the need to inject build IDs for DSO
touched by samples as the build ID cache is populated by perf
record. They can avoid some cases of symbol mis-resolution caused by
the file system changing from when a sample occurred and when the DSO
is sought.
Unlike the --buildid-mmap option, this chnage doesn't disable the
build ID cache but it does disable the processing of samples looking
for DSOs to inject build IDs for. To disable the build ID cache the -B
(--no-buildid) option should be used.
Making this option the default was raised on the list in:
https://lore.kernel.org/linux-perf-users/CAP-5=fXP7jN_QrGUcd55_QH5J-Y-FCaJ6=NaHVtyx0oyNh8_-Q@mail.gmail.com/
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250724163302.596743-9-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'tools/perf/util/synthetic-events.c')
| -rw-r--r-- | tools/perf/util/synthetic-events.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c index 3b1240c82b30..e7ca3f5eb493 100644 --- a/tools/perf/util/synthetic-events.c +++ b/tools/perf/util/synthetic-events.c @@ -532,7 +532,7 @@ out: event->mmap2.pid = tgid; event->mmap2.tid = pid; - if (symbol_conf.buildid_mmap2) + if (!symbol_conf.no_buildid_mmap2) perf_record_mmap2__read_build_id(&event->mmap2, machine, false); if (perf_tool__process_synth_event(tool, event, machine, process) != 0) { @@ -690,7 +690,7 @@ static int perf_event__synthesize_modules_maps_cb(struct map *map, void *data) return 0; dso = map__dso(map); - if (symbol_conf.buildid_mmap2) { + if (!symbol_conf.no_buildid_mmap2) { size = PERF_ALIGN(dso__long_name_len(dso) + 1, sizeof(u64)); event->mmap2.header.type = PERF_RECORD_MMAP2; event->mmap2.header.size = (sizeof(event->mmap2) - @@ -734,9 +734,9 @@ int perf_event__synthesize_modules(const struct perf_tool *tool, perf_event__han .process = process, .machine = machine, }; - size_t size = symbol_conf.buildid_mmap2 - ? sizeof(args.event->mmap2) - : sizeof(args.event->mmap); + size_t size = symbol_conf.no_buildid_mmap2 + ? sizeof(args.event->mmap) + : sizeof(args.event->mmap2); args.event = zalloc(size + machine->id_hdr_size); if (args.event == NULL) { @@ -1124,8 +1124,8 @@ static int __perf_event__synthesize_kernel_mmap(const struct perf_tool *tool, struct machine *machine) { union perf_event *event; - size_t size = symbol_conf.buildid_mmap2 ? - sizeof(event->mmap2) : sizeof(event->mmap); + size_t size = symbol_conf.no_buildid_mmap2 ? + sizeof(event->mmap) : sizeof(event->mmap2); struct map *map = machine__kernel_map(machine); struct kmap *kmap; int err; @@ -1159,7 +1159,7 @@ static int __perf_event__synthesize_kernel_mmap(const struct perf_tool *tool, event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL; } - if (symbol_conf.buildid_mmap2) { + if (!symbol_conf.no_buildid_mmap2) { size = snprintf(event->mmap2.filename, sizeof(event->mmap2.filename), "%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1; size = PERF_ALIGN(size, sizeof(u64)); |