From: Namhyung Kim <namhy...@kernel.org> When perf record finishes a session, it pre-processes samples in order to write build-id info from DSOs that had samples.
During this process it'll call map__load() for the kernel map, and it ends up calling dso__load_vmlinux_path() which replaces dso->long_name. But this function checks kernel's build-id before searching vmlinux path so it'll end up with a cryptic name, the pathname for the entry in the ~/.debug cache, which can be confusing to users. This patch adds a flag to skip the build-id check during record, so that it'll have the original vmlinux path for the kernel dso->long_name, not the entry in the ~/.debug cache. Before: # perf record -va sleep 3 mmap size 528384B [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.196 MB perf.data (~8545 samples) ] Looking at the vmlinux_path (7 entries long) Using /home/namhyung/.debug/.build-id/f0/6e17aa50adf4d00b88925e03775de107611551 for symbols After: # perf record -va sleep 3 mmap size 528384B [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.193 MB perf.data (~8432 samples) ] Looking at the vmlinux_path (7 entries long) Using /lib/modules/3.16.4-1-ARCH/build/vmlinux for symbols Signed-off-by: Namhyung Kim <namhy...@kernel.org> Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Ingo Molnar <mi...@kernel.org> Cc: Jiri Olsa <jo...@redhat.com> Cc: Namhyung Kim <namhyung....@lge.com> Cc: Paul Mackerras <pau...@samba.org> Cc: Peter Zijlstra <a.p.zijls...@chello.nl> Cc: Stephane Eranian <eran...@google.com> Link: http://lkml.kernel.org/r/1415063674-17206-7-git-send-email-namhy...@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/builtin-record.c | 11 +++++++++++ tools/perf/util/symbol.c | 11 ++++++----- tools/perf/util/symbol.h | 1 + 3 files changed, 18 insertions(+), 5 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 5091a27e6d28..582c4da155ea 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -200,6 +200,17 @@ static int process_buildids(struct record *rec) if (size == 0) return 0; + /* + * During this process, it'll load kernel map and replace the + * dso->long_name to a real pathname it found. In this case + * we prefer the vmlinux path like + * /lib/modules/3.16.4/build/vmlinux + * + * rather than build-id path (in debug directory). + * $HOME/.debug/.build-id/f0/6e17aa50adf4d00b88925e03775de107611551 + */ + symbol_conf.ignore_vmlinux_buildid = true; + return __perf_session__process_events(session, start, size - start, size, &build_id__mark_dso_hit_ops); diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index c69915c9d5bc..c24c5b83156c 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1511,12 +1511,10 @@ int dso__load_vmlinux_path(struct dso *dso, struct map *map, symbol_filter_t filter) { int i, err = 0; - char *filename; + char *filename = NULL; - pr_debug("Looking at the vmlinux_path (%d entries long)\n", - vmlinux_path__nr_entries + 1); - - filename = dso__build_id_filename(dso, NULL, 0); + if (!symbol_conf.ignore_vmlinux_buildid) + filename = dso__build_id_filename(dso, NULL, 0); if (filename != NULL) { err = dso__load_vmlinux(dso, map, filename, true, filter); if (err > 0) @@ -1524,6 +1522,9 @@ int dso__load_vmlinux_path(struct dso *dso, struct map *map, free(filename); } + pr_debug("Looking at the vmlinux_path (%d entries long)\n", + vmlinux_path__nr_entries + 1); + for (i = 0; i < vmlinux_path__nr_entries; ++i) { err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter); if (err > 0) diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index eb2c19bf8d90..ded3ca7266de 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -105,6 +105,7 @@ struct symbol_conf { unsigned short nr_events; bool try_vmlinux_path, ignore_vmlinux, + ignore_vmlinux_buildid, show_kernel_path, use_modules, sort_by_name, -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
