[tip:perf/urgent] perf: Remove superfluous allocation error check

[tip-bot for Jiri Olsa <tipbot@zytor.com>]

Commit-ID:  bfb3d7b8b906b66551424d7636182126e1d134c8
Gitweb:     https://git.kernel.org/tip/bfb3d7b8b906b66551424d7636182126e1d134c8
Author:     Jiri Olsa <jolsa@kernel.org>
AuthorDate: Sun, 15 Apr 2018 11:23:52 +0200
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 17 Apr 2018 09:47:40 -0300

perf: Remove superfluous allocation error check

If the get_callchain_buffers fails to allocate the buffer it will
decrease the nr_callchain_events right away.

There's no point of checking the allocation error for
nr_callchain_events > 1. Removing that check.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: syzkaller-bugs@googlegroups.com
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20180415092352.12403-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 kernel/events/callchain.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index 73cc26e321de..c187aa3df3c8 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -131,14 +131,8 @@ int get_callchain_buffers(int event_max_stack)
 		goto exit;
 	}
 
-	if (count > 1) {
-		/* If the allocation failed, give up */
-		if (!callchain_cpus_entries)
-			err = -ENOMEM;
-		goto exit;
-	}
-
-	err = alloc_callchain_buffers();
+	if (count == 1)
+		err = alloc_callchain_buffers();
 exit:
 	if (err)
 		atomic_dec(&nr_callchain_events);