perf evlist: Introduce strerror_mmap method
To pretty print hints about perf_evlist__mmap errors. Will be used in
'trace' in the next patch.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-2g3gczfwyz0xt3we0s15mqqt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index cfbe2b9..bb5dfc5 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -8,6 +8,7 @@
*/
#include "util.h"
#include <api/fs/debugfs.h>
+#include <api/fs/fs.h>
#include <poll.h>
#include "cpumap.h"
#include "thread_map.h"
@@ -1483,6 +1484,28 @@
return 0;
}
+int perf_evlist__strerror_mmap(struct perf_evlist *evlist, int err, char *buf, size_t size)
+{
+ char sbuf[STRERR_BUFSIZE], *emsg = strerror_r(err, sbuf, sizeof(sbuf));
+ int value;
+
+ switch (err) {
+ case EPERM:
+ sysctl__read_int("kernel/perf_event_mlock_kb", &value);
+ scnprintf(buf, size, "Error:\t%s.\n"
+ "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
+ "Hint:\tTried using %zd kB.\n"
+ "Hint:\tTry using a bigger -m/--mmap-pages value.",
+ emsg, value, evlist->mmap_len / 1024);
+ break;
+ default:
+ scnprintf(buf, size, "%s", emsg);
+ break;
+ }
+
+ return 0;
+}
+
void perf_evlist__to_front(struct perf_evlist *evlist,
struct perf_evsel *move_evsel)
{
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 649b0c5..0ba93f6 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -185,6 +185,7 @@
int perf_evlist__strerror_tp(struct perf_evlist *evlist, int err, char *buf, size_t size);
int perf_evlist__strerror_open(struct perf_evlist *evlist, int err, char *buf, size_t size);
+int perf_evlist__strerror_mmap(struct perf_evlist *evlist, int err, char *buf, size_t size);
static inline unsigned int perf_mmap__read_head(struct perf_mmap *mm)
{