From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932314AbeCEUz7 (ORCPT ); Mon, 5 Mar 2018 15:55:59 -0500 Received: from mga07.intel.com ([134.134.136.100]:23929 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752040AbeCEUz6 (ORCPT ); Mon, 5 Mar 2018 15:55:58 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,428,1515484800"; d="scan'208";a="32596877" Subject: Re: [PATCH 1/7] perf mmap: Store mmap scope and type in struct perf_mmap To: Arnaldo Carvalho de Melo Cc: mingo@redhat.com, linux-kernel@vger.kernel.org, jolsa@redhat.com, namhyung@kernel.org, wangnan0@huawei.com, ak@linux.intel.com References: <1520277059-32749-1-git-send-email-kan.liang@linux.intel.com> <20180305202054.GA10176@kernel.org> From: "Liang, Kan" Message-ID: <47c9d29d-4b99-a9b6-4af6-2320900b2ef6@linux.intel.com> Date: Mon, 5 Mar 2018 15:55:54 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180305202054.GA10176@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/5/2018 3:20 PM, Arnaldo Carvalho de Melo wrote: > Em Mon, Mar 05, 2018 at 02:10:53PM -0500, kan.liang@linux.intel.com escreveu: >> From: Kan Liang >> >> There are too many boilerplates for the perf_mmap__read*() interfaces. >> >> Some of the data (e.g. 'start', 'end', 'overwrite') should be stored in >> struct perf_mmap at initialization. They will be used later. >> >> No functional change. >> >> Signed-off-by: Kan Liang >> --- >> tools/perf/util/mmap.c | 11 ++++++++--- >> tools/perf/util/mmap.h | 3 +++ >> 2 files changed, 11 insertions(+), 3 deletions(-) >> >> diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c >> index 4f27c46..642b479 100644 >> --- a/tools/perf/util/mmap.c >> +++ b/tools/perf/util/mmap.c >> @@ -250,11 +250,14 @@ int perf_mmap__read_init(struct perf_mmap *md, bool overwrite, >> >> *startp = overwrite ? head : old; >> *endp = overwrite ? old : head; > > Why did you keep the above and haven't removed the startp/endp args? The startp/endp are used by perf_mmap__read_event(). I don't want to make all the changes in a single patch. I think it's hard to review. So I modified the interface one by one. Only changing one interface will break the usage. So the old 'startp/endp' and new 'md->start/md->end' will exist simultaneously in the first few patches. They have the same value. Patch 1,3,4 add the new 'md->start/md->end' for the three interfaces. Patch 2 uses the new 'md->start/md->end' for perf record. Patch 5,6,7 remove the old 'startp/endp' for other perf tools/test and refine the interfaces. Thanks, Kan > to > ease the conversion somehow? I'll look at the other patches, but I think > we should change the function signature here and in the callers all at > once. > > Sometimes this is ok, and probably this is one case. > > - Arnaldo > >> + md->overwrite = overwrite; >> + md->start = overwrite ? head : old; >> + md->end = overwrite ? old : head; >> >> - if (*startp == *endp) >> + if (md->start == md->end) >> return -EAGAIN; >> >> - size = *endp - *startp; >> + size = md->end - md->start; >> if (size > (unsigned long)(md->mask) + 1) { >> if (!overwrite) { >> WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n"); >> @@ -268,8 +271,10 @@ int perf_mmap__read_init(struct perf_mmap *md, bool overwrite, >> * Backward ring buffer is full. We still have a chance to read >> * most of data from it. >> */ >> - if (overwrite_rb_find_range(data, md->mask, head, startp, endp)) >> + if (overwrite_rb_find_range(data, md->mask, head, &md->start, &md->end)) >> return -EINVAL; >> + *startp = md->start; >> + *endp = md->end; >> } >> >> return 0; >> diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h >> index ec7d3a24..9359e93 100644 >> --- a/tools/perf/util/mmap.h >> +++ b/tools/perf/util/mmap.h >> @@ -20,6 +20,9 @@ struct perf_mmap { >> int fd; >> refcount_t refcnt; >> u64 prev; >> + u64 start; >> + u64 end; >> + bool overwrite; >> struct auxtrace_mmap auxtrace_mmap; >> char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8); >> }; >> -- >> 2.4.11