From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx118.postini.com [74.125.245.118]) by kanga.kvack.org (Postfix) with SMTP id 896A06B00FB for ; Thu, 4 Oct 2012 06:24:18 -0400 (EDT) Received: by mail-pb0-f41.google.com with SMTP id rq2so525751pbb.14 for ; Thu, 04 Oct 2012 03:24:17 -0700 (PDT) From: Anton Vorontsov 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> In-Reply-To: <20121004102013.GA23284@lizard> References: <20121004102013.GA23284@lizard> Sender: owner-linux-mm@kvack.org List-ID: To: Pekka Enberg Cc: John Stultz , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linaro-kernel@lists.linaro.org, patches@linaro.org 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org