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| author | Masami Hiramatsu <mhiramat@kernel.org> | 2016-08-26 01:24:42 +0900 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-09-01 09:44:14 -0300 |
| commit | 428aff82e92a29da0e4276623180f9a98f2d5b16 (patch) | |
| tree | 90b34a229cdba27e44389408b75d4b33ae9fd2ea | |
| parent | 1c20b1d15473a91e2fccecbcd2809d80ff4b4924 (diff) | |
| download | talos-op-linux-428aff82e92a29da0e4276623180f9a98f2d5b16.tar.gz talos-op-linux-428aff82e92a29da0e4276623180f9a98f2d5b16.zip | |
perf probe: Ignore vmlinux buildid if offline kernel is given
Ignore the buildid of running kernel when both of --definition and
--vmlinux is given because that kernel should be off-line.
This also skips post-processing of kprobe event for relocating symbol
and checking blacklist, because it can not be done on off-line kernel.
E.g. without this fix perf shows an error as below
----
$ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
./vmlinux-arm with build id 7a1f76dd56e9c4da707cd3d6333f50748141434b not found, continuing without symbols
Failed to find symbol do_sys_open in kernel
Error: Failed to add events.
----
with this fix, we can get the definition
----
$ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
p:probe/do_sys_open do_sys_open+0
----
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214228193.23638.12581984840822162131.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| -rw-r--r-- | tools/perf/Documentation/perf-probe.txt | 2 | ||||
| -rw-r--r-- | tools/perf/builtin-probe.c | 10 | ||||
| -rw-r--r-- | tools/perf/util/probe-event.c | 4 | ||||
| -rw-r--r-- | tools/perf/util/symbol-elf.c | 2 |
4 files changed, 16 insertions, 2 deletions
diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt index 56db4d40d27e..e6c9902c6d82 100644 --- a/tools/perf/Documentation/perf-probe.txt +++ b/tools/perf/Documentation/perf-probe.txt @@ -36,6 +36,8 @@ OPTIONS -k:: --vmlinux=PATH:: Specify vmlinux path which has debuginfo (Dwarf binary). + Only when using this with --definition, you can give an offline + vmlinux file. -m:: --module=MODNAME|PATH:: diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c index 7a3d8c47ed29..b4220cd4acd8 100644 --- a/tools/perf/builtin-probe.c +++ b/tools/perf/builtin-probe.c @@ -654,8 +654,16 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused) return ret; } break; - case 'a': case 'D': + /* + * If user gives offline vmlinux, ignore buildid, since + * --definition doesn't change running kernel. + */ + if (symbol_conf.vmlinux_name) + symbol_conf.ignore_vmlinux_buildid = true; + /* fall through */ + case 'a': + /* Ensure the last given target is used */ if (params.target && !params.target_used) { pr_err(" Error: -x/-m must follow the probe definitions.\n"); diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 4a49cb8ce7ab..8a1e9e67614f 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -674,6 +674,10 @@ post_process_kernel_probe_trace_events(struct probe_trace_event *tevs, char *tmp; int i, skipped = 0; + /* Skip post process if the target is an offline kernel */ + if (symbol_conf.ignore_vmlinux_buildid) + return 0; + reloc_sym = kernel_get_ref_reloc_sym(); if (!reloc_sym) { pr_warning("Relocated base symbol is not found!\n"); diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index fbe31eff1beb..e680371bd5c9 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -732,7 +732,7 @@ 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) { |
