There's no need to receive events from overwritable ring buffer. Instead,
perf should make them run background until something happen. This patch
makes normal events from overwrite ring buffer ignored.
Signed-off-by: Wang Nan <wangn...@huawei.com>
Signed-off-by: He Kuang <heku...@huawei.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Cc: Jiri Olsa <jo...@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Zefan Li <lize...@huawei.com>
Cc: pi3or...@163.com
---
tools/perf/util/evlist.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index abce588..f0b0457 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -461,9 +461,9 @@ int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
return 0;
}
-static int __perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd, int
idx)
+static int __perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd, int
idx, short revent)
{
- int pos = fdarray__add(&evlist->pollfd, fd, POLLIN | POLLERR | POLLHUP);
+ int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP);
/*
* Save the idx so that when we filter out fds POLLHUP'ed we can
* close the associated evlist->mmap[] entry.
@@ -479,7 +479,7 @@ static int __perf_evlist__add_pollfd(struct perf_evlist
*evlist, int fd, int idx
int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
{
- return __perf_evlist__add_pollfd(evlist, fd, -1);
+ return __perf_evlist__add_pollfd(evlist, fd, -1, POLLIN);
}
static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd)
@@ -1077,6 +1077,18 @@ perf_evlist__channel_complete(struct perf_evlist *evlist)
return 0;
}
+static bool
+perf_evlist__should_poll(struct perf_evlist *evlist,
+ struct perf_evsel *evsel,
+ int channel)
+{
+ if (evsel->system_wide)
+ return false;
+ if (perf_evlist__channel_check(evlist, channel, RDONLY))
+ return false;
+ return true;
+}
+
static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int _idx,
struct mmap_params *mp, int cpu,
int thread, int *outputs)
@@ -1085,6 +1097,7 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist
*evlist, int _idx,
evlist__for_each(evlist, evsel) {
int fd, channel, idx, err;
+ short revent = POLLIN;
channel = perf_evlist__channel_find(evlist, evsel, false);
if (channel < 0) {
@@ -1114,6 +1127,8 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist
*evlist, int _idx,
perf_evlist__mmap_get(evlist, idx);
}
+ if (!perf_evlist__should_poll(evlist, evsel, channel))
+ revent = 0;
/*
* The system_wide flag causes a selected event to be opened
* always without a pid. Consequently it will never get a
@@ -1122,7 +1137,7 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist
*evlist, int _idx,
* Therefore don't add it for polling.
*/
if (!evsel->system_wide &&
- __perf_evlist__add_pollfd(evlist, fd, idx) < 0) {
+ __perf_evlist__add_pollfd(evlist, fd, idx, revent) < 0) {
perf_evlist__mmap_put(evlist, idx);
return -1;
}
--
1.8.3.4
