[RFC PATCH 3/4] perf-probe: Ignore vmlinux buildid if offline kernel is given

From: Masami Hiramatsu
Date: Wed Aug 24 2016 - 01:58:41 EST


Ignore the buildid of running kernel when both --outdir and
--vmlinux is given and --outdir is not tracing_path,
because that kernel should be off-line.

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
tools/perf/builtin-probe.c | 6 ++++++
tools/perf/util/symbol-elf.c | 2 +-
2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 5b45ec8..773cea0 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -602,6 +602,12 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
*/
symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);

+ /* If user gives output directory and offline vmlinux, ignore buildid */
+ if (probe_conf.output_dir && symbol_conf.vmlinux_name &&
+ strcmp(probe_conf.output_dir, tracing_path) != 0) {
+ symbol_conf.ignore_vmlinux_buildid = true;
+ }
+
switch (params.command) {
case 'l':
if (params.uprobes) {
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index a811c13..013cebf 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -685,7 +685,7 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
}

/* Always reject images with a mismatched build-id: */
- if (dso->has_build_id) {
+ if (dso->has_build_id && !symbol_conf.ignore_vmlinux_buildid) {
u8 build_id[BUILD_ID_SIZE];

if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0) {