Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753694Ab2JDKYW (ORCPT ); Thu, 4 Oct 2012 06:24:22 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:59781 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752975Ab2JDKYS (ORCPT ); Thu, 4 Oct 2012 06:24:18 -0400 From: Anton Vorontsov To: Pekka Enberg Cc: John Stultz , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org, patches@linaro.org Subject: [PATCH 3/3] vmevent: Don't sample values twice Date: Thu, 4 Oct 2012 03:21:18 -0700 Message-Id: <1349346078-24874-3-git-send-email-anton.vorontsov@linaro.org> X-Mailer: git-send-email 1.7.12.1 In-Reply-To: <20121004102013.GA23284@lizard> References: <20121004102013.GA23284@lizard> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1739 Lines: 67 Currently, we sample the same values in vmevent_sample() and vmevent_match(), but we can easily avoid this. Also saves loop iterations. Signed-off-by: Anton Vorontsov --- mm/vmevent.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/mm/vmevent.c b/mm/vmevent.c index d434c11..d643615 100644 --- a/mm/vmevent.c +++ b/mm/vmevent.c @@ -133,18 +133,22 @@ static bool vmevent_match_attr(struct vmevent_attr *attr, u64 value) static bool vmevent_match(struct vmevent_watch *watch) { struct vmevent_config *config = &watch->config; + bool ret = 0; int i; for (i = 0; i < config->counter; i++) { struct vmevent_attr *attr = &config->attrs[i]; + struct vmevent_attr *samp = &watch->sample_attrs[i]; u64 val; val = vmevent_sample_attr(watch, attr); - if (vmevent_match_attr(attr, val)) - return true; + if (!ret && vmevent_match_attr(attr, val)) + ret = 1; + + samp->value = val; } - return false; + return ret; } /* @@ -161,20 +165,11 @@ static bool vmevent_match(struct vmevent_watch *watch) */ static void vmevent_sample(struct vmevent_watch *watch) { - int i; - if (atomic_read(&watch->pending)) return; if (!vmevent_match(watch)) return; - for (i = 0; i < watch->nr_attrs; i++) { - struct vmevent_attr *attr = &watch->sample_attrs[i]; - - attr->value = vmevent_sample_attr(watch, - watch->config_attrs[i]); - } - atomic_set(&watch->pending, 1); } -- 1.7.12.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/