diff --git a/tools/perf/Documentation/perf-trace.txt b/tools/perf/Documentation/perf-trace.txt
index 54139c6457f8..7b0497f95a75 100644
--- a/tools/perf/Documentation/perf-trace.txt
+++ b/tools/perf/Documentation/perf-trace.txt
@@ -97,6 +97,10 @@ the thread executes on the designated CPUs. Default is to monitor all CPUs.
Show a summary of syscalls by thread with min, max, and average times (in
msec) and relative stddev.
+--tool_stats::
+ Show tool stats such as number of times fd->pathname was discovered thru
+ hooking the open syscall return + vfs_getname or via reading /proc/pid/fd, etc.
+
SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-script[1]
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 763bef45afad..86d2b1f2399c 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -951,7 +951,10 @@ fail:
struct trace {
struct perf_tool tool;
- int audit_machine;
+ struct {
+ int machine;
+ int open_id;
+ } audit;
struct {
int max;
struct syscall *table;
@@ -965,14 +968,19 @@ struct trace {
struct strlist *ev_qualifier;
bool not_ev_qualifier;
bool live;
+ const char *last_vfs_getname;
struct intlist *tid_list;
struct intlist *pid_list;
bool sched;
bool multiple_threads;
bool summary;
bool show_comm;
+ bool show_tool_stats;
double duration_filter;
double runtime_ms;
+ struct {
+ u64 vfs_getname, proc_getname;
+ } stats;
};
static int trace__set_fd_pathname(struct thread *thread, int fd, const char *pathname)
@@ -1027,7 +1035,8 @@ static int thread__read_fd_path(struct thread *thread, int fd)
return trace__set_fd_pathname(thread, fd, pathname);
}
-static const char *thread__fd_path(struct thread *thread, int fd, bool live)
+static const char *thread__fd_path(struct thread *thread, int fd,
+ struct trace *trace)
{
struct thread_trace *ttrace = thread->priv;
@@ -1037,9 +1046,13 @@ static const char *thread__fd_path(struct thread *thread, int fd, bool live)
if (fd < 0)
return NULL;
- if ((fd > ttrace->paths.max || ttrace->paths.table[fd] == NULL) &&
- (!live || thread__read_fd_path(thread, fd)))
- return NULL;
+ if ((fd > ttrace->paths.max || ttrace->paths.table[fd] == NULL))
+ if (!trace->live)
+ return NULL;
+ ++trace->stats.proc_getname;
+ if (thread__read_fd_path(thread, fd)) {
+ return NULL;
+ }
return ttrace->paths.table[fd];
}
@@ -1049,7 +1062,7 @@ static size_t syscall_arg__scnprintf_fd(char *bf, size_t size,
{
int fd = arg->val;
size_t printed = scnprintf(bf, size, "%d", fd);
- const char *path = thread__fd_path(arg->thread, fd, arg->trace->live);
+ const char *path = thread__fd_path(arg->thread, fd, arg->trace);
if (path)
printed += scnprintf(bf + printed, size - printed, "<%s>", path);
@@ -1186,7 +1199,7 @@ static int trace__read_syscall_info(struct trace *trace, int id)
{
char tp_name[128];
struct syscall *sc;
- const char *name = audit_syscall_to_name(id, trace->audit_machine);
+ const char *name = audit_syscall_to_name(id, trace->audit.machine);
if (name == NULL)
return -1;
@@ -1450,6 +1463,12 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
ret = perf_evsel__intval(evsel, sample, "ret");
+ if (id == trace->audit.open_id && ret >= 0 && trace->last_vfs_getname) {
+ trace__set_fd_pathname(thread, ret, trace->last_vfs_getname);
+ trace->last_vfs_getname = NULL;
+ ++trace->stats.vfs_getname;
+ }
+
ttrace = thread->priv;
ttrace->exit_time = sample->time;
@@ -1494,6 +1513,13 @@ out:
return 0;
}
+static int trace__vfs_getname(struct trace *trace, struct perf_evsel *evsel,
+ struct perf_sample *sample)
+{
+ trace->last_vfs_getname = perf_evsel__rawptr(evsel, sample, "pathname");
+ return 0;
+}
+
static int trace__sched_stat_runtime(struct trace *trace, struct perf_evsel *evsel,
struct perf_sample *sample)
{
@@ -1616,6 +1642,22 @@ static int trace__record(int argc, const char **argv)
static size_t trace__fprintf_thread_summary(struct trace *trace, FILE *fp);
+static void perf_evlist__add_vfs_getname(struct perf_evlist *evlist)
+{
+ struct perf_evsel *evsel = perf_evsel__newtp("probe", "vfs_getname",
+ evlist->nr_entries);
+ if (evsel == NULL)
+ return;
+
+ if (perf_evsel__field(evsel, "pathname") == NULL) {
+ perf_evsel__delete(evsel);
+ return;
+ }
+
+ evsel->handler.func = trace__vfs_getname;
+ perf_evlist__add(evlist, evsel);
+}
+
static int trace__run(struct trace *trace, int argc, const char **argv)
{
struct perf_evlist *evlist = perf_evlist__new();
@@ -1635,6 +1677,8 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
perf_evlist__add_newtp(evlist, "raw_syscalls", "sys_exit", trace__sys_exit))
goto out_error_tp;
+ perf_evlist__add_vfs_getname(evlist);
+
if (trace->sched &&
perf_evlist__add_newtp(evlist, "sched", "sched_stat_runtime",
trace__sched_stat_runtime))
@@ -1741,12 +1785,22 @@ again:
if (done)
perf_evlist__disable(evlist);
-
- goto again;
+ else
+ goto again;
out_unmap_evlist:
- if (!err && trace->summary)
- trace__fprintf_thread_summary(trace, trace->output);
+ if (!err) {
+ if (trace->summary)
+ trace__fprintf_thread_summary(trace, trace->output);
+
+ if (trace->show_tool_stats) {
+ fprintf(trace->output, "Stats:\n "
+ " vfs_getname : %" PRIu64 "\n"
+ " proc_getname: %" PRIu64 "\n",
+ trace->stats.vfs_getname,
+ trace->stats.proc_getname);
+ }
+ }
perf_evlist__munmap(evlist);
out_close_evlist:
@@ -1788,6 +1842,7 @@ static int trace__replay(struct trace *trace)
const struct perf_evsel_str_handler handlers[] = {
{ "raw_syscalls:sys_enter", trace__sys_enter, },
{ "raw_syscalls:sys_exit", trace__sys_exit, },
+ { "probe:vfs_getname", trace__vfs_getname, },
};
struct perf_session *session;
@@ -1997,7 +2052,10 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
NULL
};
struct trace trace = {
- .audit_machine = audit_detect_machine(),
+ .audit = {
+ .machine = audit_detect_machine(),
+ .open_id = audit_name_to_syscall("open", trace.audit.machine),
+ },
.syscalls = {
. max = -1,
},
@@ -2019,6 +2077,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
const struct option trace_options[] = {
OPT_BOOLEAN(0, "comm", &trace.show_comm,
"show the thread COMM next to its id"),
+ OPT_BOOLEAN(0, "tool_stats", &trace.show_tool_stats, "show tool stats"),
OPT_STRING('e', "expr", &ev_qualifier_str, "expr",
"list of events to trace"),
OPT_STRING('o', "output", &output_name, "file", "output file name"),