From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965064AbaGCQMm (ORCPT ); Thu, 3 Jul 2014 12:12:42 -0400 Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.231]:62039 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759160AbaGCQM1 (ORCPT ); Thu, 3 Jul 2014 12:12:27 -0400 Message-Id: <20140703161226.246757842@goodmis.org> User-Agent: quilt/0.63-1 Date: Thu, 03 Jul 2014 12:05:19 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Namhyung Kim Subject: [for-next][PATCH 16/21] ftrace: Do not copy hash if O_TRUNC is set References: <20140703160503.006976702@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline; filename=0016-ftrace-Do-not-copy-hash-if-O_TRUNC-is-set.patch X-RR-Connecting-IP: 107.14.168.142:25 X-Cloudmark-Score: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Namhyung Kim When a filter file is open for writing and O_TRUNC is set, there's no need to copy and free the filter entries. Link: http://lkml.kernel.org/p/1402474014-28655-2-git-send-email-namhyung@kernel.org Signed-off-by: Namhyung Kim Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index e14ff4c1713e..232b898eebbd 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3010,7 +3010,13 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, hash = ops->filter_hash; if (file->f_mode & FMODE_WRITE) { - iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); + const int size_bits = FTRACE_HASH_DEFAULT_BITS; + + if (file->f_flags & O_TRUNC) + iter->hash = alloc_ftrace_hash(size_bits); + else + iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); + if (!iter->hash) { trace_parser_put(&iter->parser); kfree(iter); @@ -3019,10 +3025,6 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag, } } - if ((file->f_mode & FMODE_WRITE) && - (file->f_flags & O_TRUNC)) - ftrace_filter_reset(iter->hash); - if (file->f_mode & FMODE_READ) { iter->pg = ftrace_pages_start; -- 2.0.0