perf util: Fix do_read() to fail on EOF instead of busy-looping
While toying with perf, I've noticed that perf record can
easily enter a busy loop when doing something as silly as:
$ perf record -A ls
Yeah, do_read here really wants to read a known size, not being
able to should die(), not busy-loop ;)
That was the cause for the bug.
Signed-off-by: Pierre Habouzit <pierre.habouzit@intersec.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 95a44bc..b92a457 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -185,6 +185,8 @@
if (ret < 0)
die("failed to read");
+ if (ret == 0)
+ die("failed to read: missing data");
size -= ret;
buf += ret;