perf_event: Make perf fd non seekable

Perf_event does not need seeking, so prevent it in order to
get rid of default_llseek, which uses the BKL.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
[drop the nonseekable_open, not needed for anon inodes]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 63fbce1..4aa50ff 100644 (file)
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -2645,6 +2645,7 @@ static int perf_fasync(int fd, struct file *filp, int on)
 }
 
 static const struct file_operations perf_fops = {
+       .llseek                 = no_llseek,
        .release                = perf_release,
        .read                   = perf_read,
        .poll                   = perf_poll,