[PATCH perf/core v11 07/20] perf probe: Add --cache option to cache the probe definitions

Masami Hiramatsu
2016-06-15T03:28:53Z

From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

Add --cache option to cache the probe definitions. This
just saves the result of the dwarf analysis to probe cache.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
Changes in v11:
- Check failure of probe_cache operations and warn it.
Changes in v10:
- Split into 5 subpatches.
Changes in v6:
- Remove unneeded O_APPEND from open(). (Thanks Namhyung!)
- Fix to check the return value of probe_cache_entry__new and strdup.(ditto)
Changes in v5:
- Move probe_cache* definitions. (code cleanup)

Changes in v4:
- Remove cache saving failure message.
---
tools/perf/Documentation/perf-probe.txt | 4 ++++
tools/perf/builtin-probe.c | 1 +
tools/perf/util/probe-event.c | 9 +++++++++
tools/perf/util/probe-event.h | 1 +
4 files changed, 15 insertions(+)

diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt
index 3a8a9ba..947db6f 100644
--- a/tools/perf/Documentation/perf-probe.txt
+++ b/tools/perf/Documentation/perf-probe.txt
@@ -109,6 +109,10 @@ OPTIONS
Dry run. With this option, --add and --del doesn't execute actual
adding and removal operations.

+--cache::
+ Cache the probes (with --add option). Any events which successfully added
+ are also stored in the cache file.
+
--max-probes=NUM::
Set the maximum number of probe points for an event. Default is 128.

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 9af859b..6d7ab431 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -512,6 +512,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
"Enable symbol demangling"),
OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
"Enable kernel symbol demangling"),
+ OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
OPT_END()
};
int ret;
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index cbc8a8b..084756c 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2514,6 +2514,7 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
{
int i, fd, ret;
struct probe_trace_event *tev = NULL;
+ struct probe_cache *cache = NULL;
struct strlist *namelist;

fd = probe_file__open(PF_FL_RW | (pev->uprobes ? PF_FL_UPROBE : 0));
@@ -2555,6 +2556,14 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
}
if (ret == -EINVAL && pev->uprobes)
warn_uprobe_event_compat(tev);
+ if (ret == 0 && probe_conf.cache) {
+ cache = probe_cache__new(pev->target);
+ if (!cache ||
+ probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 ||
+ probe_cache__commit(cache) < 0)
+ pr_warning("Failed to add event to probe cache\n");
+ probe_cache__delete(cache);
+ }

strlist__delete(namelist);
close_out:
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 0b024ba..432b690 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -12,6 +12,7 @@ struct probe_conf {
bool show_location_range;
bool force_add;
bool no_inlines;
+ bool cache;
int max_probes;
};
extern struct probe_conf probe_conf;