From patchwork Wed Apr 27 02:19:20 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Nan X-Patchwork-Id: 66756 Delivered-To: patch@linaro.org Received: by 10.140.93.198 with SMTP id d64csp1937282qge; Tue, 26 Apr 2016 19:21:22 -0700 (PDT) X-Received: by 10.66.75.97 with SMTP id b1mr8251876paw.54.1461723682428; Tue, 26 Apr 2016 19:21:22 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id t4si2304080pai.76.2016.04.26.19.21.22; Tue, 26 Apr 2016 19:21:22 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752804AbcD0CVL (ORCPT + 29 others); Tue, 26 Apr 2016 22:21:11 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:35321 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752524AbcD0CVD (ORCPT ); Tue, 26 Apr 2016 22:21:03 -0400 Received: from 172.24.1.137 (EHLO szxeml426-hub.china.huawei.com) ([172.24.1.137]) by szxrg03-dlp.huawei.com (MOS 4.4.3-GA FastPath queued) with ESMTP id CAQ09350; Wed, 27 Apr 2016 10:19:40 +0800 (CST) Received: from linux-4hy3.site (10.107.193.248) by szxeml426-hub.china.huawei.com (10.82.67.181) with Microsoft SMTP Server id 14.3.235.1; Wed, 27 Apr 2016 10:19:28 +0800 From: Wang Nan To: CC: , Wang Nan , "Arnaldo Carvalho de Melo" , Peter Zijlstra , Zefan Li , Subject: [PATCH v2 1/4] perf tools: Extract perf_mmap__read() Date: Wed, 27 Apr 2016 02:19:20 +0000 Message-ID: <1461723563-67451-2-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1461723563-67451-1-git-send-email-wangnan0@huawei.com> References: <1461723563-67451-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A0B0206.572021BC.00C5, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 1722ca2a09f587d4994b97da9fc0ef40 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Extract event reader from perf_evlist__mmap_read() to perf__mmap_read(). Future commit will feed it with manually computed 'head' and 'old' pointers. Signed-off-by: Wang Nan Cc: Arnaldo Carvalho de Melo Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com --- tools/perf/util/evlist.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) -- 1.8.3.4 diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 85271e5..96c7191 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -679,24 +679,15 @@ static struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist, return NULL; } -union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) +static union perf_event * +perf_mmap__read(struct perf_mmap *md, bool overwrite, u64 head, + u64 old, u64 *prev) { - struct perf_mmap *md = &evlist->mmap[idx]; - u64 head; - u64 old = md->prev; - int diff; unsigned char *data = md->base + page_size; union perf_event *event = NULL; + int diff = head - old; - /* - * Check if event was unmapped due to a POLLHUP/POLLERR. - */ - if (!atomic_read(&md->refcnt)) - return NULL; - - head = perf_mmap__read_head(md); - diff = head - old; - if (evlist->overwrite) { + if (overwrite) { /* * If we're further behind than half the buffer, there's a chance * the writer will bite our tail and mess up the samples under us. @@ -751,11 +742,29 @@ union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) } broken_event: - md->prev = old; + if (prev) + *prev = old; return event; } +union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) +{ + struct perf_mmap *md = &evlist->mmap[idx]; + u64 head; + u64 old = md->prev; + + /* + * Check if event was unmapped due to a POLLHUP/POLLERR. + */ + if (!atomic_read(&md->refcnt)) + return NULL; + + head = perf_mmap__read_head(md); + + return perf_mmap__read(md, evlist->overwrite, head, old, &md->prev); +} + static bool perf_mmap__empty(struct perf_mmap *md) { return perf_mmap__read_head(md) == md->prev && !md->auxtrace_mmap.base;