linux-kernel - Re: [PATCH v7] perf annotate: Fix sample events lost in stdio mode

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Date:   Mon, 12 Apr 2021 15:22:29 +0800
From:   Yang Jihong <yangjihong1@...wei.com>
To:     Arnaldo Carvalho de Melo <acme@...nel.org>
CC:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...hat.com>,
        Yao Jin <yao.jin@...ux.intel.com>, <gustavoars@...nel.org>,
        <mliska@...e.cz>, linux-kernel <linux-kernel@...r.kernel.org>,
        <zhangjinhao2@...wei.com>, Namhyung Kim <namhyung@...nel.org>
Subject: Re: [PATCH v7] perf annotate: Fix sample events lost in stdio mode

Hello, Arnaldo,

On 2021/3/31 10:18, Yang Jihong wrote:
> Hello, Namhyung  and Arnaldo,
> 
> On 2021/3/30 15:26, Namhyung Kim wrote:
>> Hi Yang and Arnaldo,
>>
>> On Sat, Mar 27, 2021 at 11:16 AM Yang Jihong <yangjihong1@...wei.com> 
>> wrote:
>>> On 2021/3/26 20:06, Arnaldo Carvalho de Melo wrote:
>>>> So it seems to be working, what am I missing? Is this strictly non
>>>> group related?
>>>>
>>> Yes, it is non group related.
>>> This problem occurs only when different events need to be recorded at
>>> the same time, i.e.:
>>> perf record -e branch-misses -e branch-instructions -a sleep 1
>>>
>>> The output results of perf script and perf annotate do not match.
>>> Some events are not output in perf annotate.
>>
>> Yeah I think it's related to sort keys.  The code works with a single
>> hist_entry for each event and symbol.  But the default sort key
>> creates multiple entries for different threads and it causes the
>> confusion.
>>
> Yes, After revome zfree from hists__find_annotations, the output of perf 
> annotate is repeated, which is related to sort keys.
> 
> The original problem is that notes->src may correspond to multiple 
> sample events. Therefore, we cannot simply zfree notes->src to avoid 
> repeated output.
> 
> Arnaldo, is there any problem with this patch? :)
> 
> Thanks,
> Yang
>> Thanks,
>> Namhyung
>> .
>>
PING :)
Is there any problem with this patch that needs to be modified?

Thanks,
Yang