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Diffstat (limited to 'tools/perf/util/evsel.c')
-rw-r--r--tools/perf/util/evsel.c72
1 files changed, 59 insertions, 13 deletions
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 7835e05f0c0a..66d066f18b5b 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -295,7 +295,6 @@ struct perf_evsel *perf_evsel__new_cycles(bool precise)
if (!precise)
goto new_event;
- perf_event_attr__set_max_precise_ip(&attr);
/*
* Now let the usual logic to set up the perf_event_attr defaults
* to kick in when we return and before perf_evsel__open() is called.
@@ -305,6 +304,8 @@ new_event:
if (evsel == NULL)
goto out;
+ evsel->precise_max = true;
+
/* use asprintf() because free(evsel) assumes name is allocated */
if (asprintf(&evsel->name, "cycles%s%s%.*s",
(attr.precise_ip || attr.exclude_kernel) ? ":" : "",
@@ -1083,7 +1084,7 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts,
}
if (evsel->precise_max)
- perf_event_attr__set_max_precise_ip(attr);
+ attr->precise_ip = 3;
if (opts->all_user) {
attr->exclude_kernel = 1;
@@ -1749,6 +1750,59 @@ static bool ignore_missing_thread(struct perf_evsel *evsel,
return true;
}
+static void display_attr(struct perf_event_attr *attr)
+{
+ if (verbose >= 2) {
+ fprintf(stderr, "%.60s\n", graph_dotted_line);
+ fprintf(stderr, "perf_event_attr:\n");
+ perf_event_attr__fprintf(stderr, attr, __open_attr__fprintf, NULL);
+ fprintf(stderr, "%.60s\n", graph_dotted_line);
+ }
+}
+
+static int perf_event_open(struct perf_evsel *evsel,
+ pid_t pid, int cpu, int group_fd,
+ unsigned long flags)
+{
+ int precise_ip = evsel->attr.precise_ip;
+ int fd;
+
+ while (1) {
+ pr_debug2("sys_perf_event_open: pid %d cpu %d group_fd %d flags %#lx",
+ pid, cpu, group_fd, flags);
+
+ fd = sys_perf_event_open(&evsel->attr, pid, cpu, group_fd, flags);
+ if (fd >= 0)
+ break;
+
+ /*
+ * Do quick precise_ip fallback if:
+ * - there is precise_ip set in perf_event_attr
+ * - maximum precise is requested
+ * - sys_perf_event_open failed with ENOTSUP error,
+ * which is associated with wrong precise_ip
+ */
+ if (!precise_ip || !evsel->precise_max || (errno != ENOTSUP))
+ break;
+
+ /*
+ * We tried all the precise_ip values, and it's
+ * still failing, so leave it to standard fallback.
+ */
+ if (!evsel->attr.precise_ip) {
+ evsel->attr.precise_ip = precise_ip;
+ break;
+ }
+
+ pr_debug2("\nsys_perf_event_open failed, error %d\n", -ENOTSUP);
+ evsel->attr.precise_ip--;
+ pr_debug2("decreasing precise_ip by one (%d)\n", evsel->attr.precise_ip);
+ display_attr(&evsel->attr);
+ }
+
+ return fd;
+}
+
int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
struct thread_map *threads)
{
@@ -1824,12 +1878,7 @@ retry_sample_id:
if (perf_missing_features.sample_id_all)
evsel->attr.sample_id_all = 0;
- if (verbose >= 2) {
- fprintf(stderr, "%.60s\n", graph_dotted_line);
- fprintf(stderr, "perf_event_attr:\n");
- perf_event_attr__fprintf(stderr, &evsel->attr, __open_attr__fprintf, NULL);
- fprintf(stderr, "%.60s\n", graph_dotted_line);
- }
+ display_attr(&evsel->attr);
for (cpu = 0; cpu < cpus->nr; cpu++) {
@@ -1841,13 +1890,10 @@ retry_sample_id:
group_fd = get_group_fd(evsel, cpu, thread);
retry_open:
- pr_debug2("sys_perf_event_open: pid %d cpu %d group_fd %d flags %#lx",
- pid, cpus->map[cpu], group_fd, flags);
-
test_attr__ready();
- fd = sys_perf_event_open(&evsel->attr, pid, cpus->map[cpu],
- group_fd, flags);
+ fd = perf_event_open(evsel, pid, cpus->map[cpu],
+ group_fd, flags);
FD(evsel, cpu, thread) = fd;