[RFC PATCH v7 31/37] perf probe: Attach trace_probe_event with perf_probe_event

Wang Nan
2015-06-12T05:38:39Z

This patch drops struct __event_package structure. Instead, it adds
trace_probe_event into 'struct perf_probe_event'.

trace_probe_event information give further patches a chance to access
actual probe points and actual arguments. Using them, bpf_loader will
be able to attach one bpf program to different probing points of a
inline functions (which has multiple probing points) and glob
functions. Moreover, by reading arguments information, bpf code for
reading those arguments can be generated.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
---
tools/perf/builtin-probe.c | 2 +-
tools/perf/util/probe-event.c | 57 +++++++++++++++++++++----------------------
tools/perf/util/probe-event.h | 5 +++-
3 files changed, 33 insertions(+), 31 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 1272559..0218725 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -497,7 +497,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
usage_with_options(probe_usage, options);
}

- ret = add_perf_probe_events(params.events, params.nevents);
+ ret = add_perf_probe_events(params.events, params.nevents, true);
if (ret < 0) {
pr_err_with_code(" Error: Failed to add events.", ret);
return ret;
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index d4cf50b..1609a5e 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1878,6 +1878,9 @@ void clear_perf_probe_event(struct perf_probe_event *pev)
struct perf_probe_arg_field *field, *next;
int i;

+ if (pev->ntevs)
+ cleanup_perf_probe_event(pev);
+
free(pev->event);
free(pev->group);
free(pev->target);
@@ -2685,56 +2688,52 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
return find_probe_trace_events_from_map(pev, tevs);
}

-struct __event_package {
- struct perf_probe_event *pev;
- struct probe_trace_event *tevs;
- int ntevs;
-};
-
-int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
+int cleanup_perf_probe_event(struct perf_probe_event *pev)
{
- int i, j, ret;
- struct __event_package *pkgs;
+ int i;

- ret = 0;
- pkgs = zalloc(sizeof(struct __event_package) * npevs);
+ if (!pev || !pev->ntevs)
+ return 0;

- if (pkgs == NULL)
- return -ENOMEM;
+ for (i = 0; i < pev->ntevs; i++)
+ clear_probe_trace_event(&pev->tevs[i]);
+
+ zfree(&pev->tevs);
+ pev->ntevs = 0;
+ return 0;
+}
+
+int add_perf_probe_events(struct perf_probe_event *pevs, int npevs, bool cleanup)
+{
+ int i, ret;

ret = init_symbol_maps(pevs->uprobes);
- if (ret < 0) {
- free(pkgs);
+ if (ret < 0)
return ret;
- }

/* Loop 1: convert all events */
for (i = 0; i < npevs; i++) {
- pkgs[i].pev = &pevs[i];
/* Convert with or without debuginfo */
- ret = convert_to_probe_trace_events(pkgs[i].pev,
- &pkgs[i].tevs);
- if (ret < 0)
+ ret = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs);
+ if (ret < 0) {
+ cleanup = true;
goto end;
- pkgs[i].ntevs = ret;
+ }
+ pevs[i].ntevs = ret;
}

/* Loop 2: add all events */
for (i = 0; i < npevs; i++) {
- ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
- pkgs[i].ntevs,
+ ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs,
+ pevs[i].ntevs,
probe_conf.force_add);
if (ret < 0)
break;
}
end:
/* Loop 3: cleanup and free trace events */
- for (i = 0; i < npevs; i++) {
- for (j = 0; j < pkgs[i].ntevs; j++)
- clear_probe_trace_event(&pkgs[i].tevs[j]);
- zfree(&pkgs[i].tevs);
- }
- free(pkgs);
+ for (i = 0; cleanup && (i < npevs); i++)
+ cleanup_perf_probe_event(&pevs[i]);
exit_symbol_maps();

return ret;
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 31db6ee..40dd22b 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -86,6 +86,8 @@ struct perf_probe_event {
bool uprobes; /* Uprobe event flag */
char *target; /* Target binary */
struct perf_probe_arg *args; /* Arguments */
+ struct probe_trace_event *tevs;
+ int ntevs;
};

/* Line range */
@@ -131,8 +133,9 @@ extern void line_range__clear(struct line_range *lr);
/* Initialize line range */
extern int line_range__init(struct line_range *lr);

-extern int add_perf_probe_events(struct perf_probe_event *pevs, int npevs);
+extern int add_perf_probe_events(struct perf_probe_event *pevs, int npevs, bool cleanup);
extern int del_perf_probe_events(struct strfilter *filter);
+extern int cleanup_perf_probe_event(struct perf_probe_event *pev);
extern int show_perf_probe_events(struct strfilter *filter);
extern int show_line_range(struct line_range *lr, const char *module,
bool user);
--
1.8.3.4