[tip:perf/core] perf unwind: Add initialized arg into unwind__prepare_access

From: tip-bot for Jiri Olsa
Date: Tue Jul 05 2016 - 06:21:23 EST


Commit-ID: a2873325ffb21cecca8032673eb698cb4d778dc6
Gitweb: http://git.kernel.org/tip/a2873325ffb21cecca8032673eb698cb4d778dc6
Author: Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Mon, 4 Jul 2016 14:16:22 +0200
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 4 Jul 2016 20:27:12 -0300

perf unwind: Add initialized arg into unwind__prepare_access

Adding initialized arg into unwind__prepare_access to get feedback about
the initialization state.

It's not possible to get it from error code, because we return 0 even in
case we don't recognize dso, which is valid.

The 'initialized' value is used in following patch to speedup
unwind__prepare_access calls logic in fork path.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1467634583-29147-4-git-send-email-jolsa@xxxxxxxxxx
[ Remove ; after static inline function signatures, fixes build break ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/thread.c | 2 +-
tools/perf/util/unwind-libunwind.c | 11 +++++++++--
tools/perf/util/unwind.h | 9 ++++++---
3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index f30f956..2439b12 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -202,7 +202,7 @@ int thread__insert_map(struct thread *thread, struct map *map)
{
int ret;

- ret = unwind__prepare_access(thread, map);
+ ret = unwind__prepare_access(thread, map, NULL);
if (ret)
return ret;

diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index 8547119..6d542a4 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -14,15 +14,19 @@ static void unwind__register_ops(struct thread *thread,
thread->unwind_libunwind_ops = ops;
}

-int unwind__prepare_access(struct thread *thread, struct map *map)
+int unwind__prepare_access(struct thread *thread, struct map *map,
+ bool *initialized)
{
const char *arch;
enum dso_type dso_type;
struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
+ int err;

if (thread->addr_space) {
pr_debug("unwind: thread map already set, dso=%s\n",
map->dso->name);
+ if (initialized)
+ *initialized = true;
return 0;
}

@@ -51,7 +55,10 @@ int unwind__prepare_access(struct thread *thread, struct map *map)
out_register:
unwind__register_ops(thread, ops);

- return thread->unwind_libunwind_ops->prepare_access(thread);
+ err = thread->unwind_libunwind_ops->prepare_access(thread);
+ if (initialized)
+ *initialized = err ? false : true;
+ return err;
}

void unwind__flush_access(struct thread *thread)
diff --git a/tools/perf/util/unwind.h b/tools/perf/util/unwind.h
index 84c6d44..61fb1e9 100644
--- a/tools/perf/util/unwind.h
+++ b/tools/perf/util/unwind.h
@@ -42,12 +42,14 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
#endif

int LIBUNWIND__ARCH_REG_ID(int regnum);
-int unwind__prepare_access(struct thread *thread, struct map *map);
+int unwind__prepare_access(struct thread *thread, struct map *map,
+ bool *initialized);
void unwind__flush_access(struct thread *thread);
void unwind__finish_access(struct thread *thread);
#else
static inline int unwind__prepare_access(struct thread *thread __maybe_unused,
- struct map *map __maybe_unused)
+ struct map *map __maybe_unused,
+ bool *initialized __maybe_unused)
{
return 0;
}
@@ -67,7 +69,8 @@ unwind__get_entries(unwind_entry_cb_t cb __maybe_unused,
}

static inline int unwind__prepare_access(struct thread *thread __maybe_unused,
- struct map *map __maybe_unused)
+ struct map *map __maybe_unused,
+ bool *initialized __maybe_unused)
{
return 0;
}