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Date:   Fri, 26 Aug 2022 20:34:20 +0300
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Subject: Re: [PATCH v3 11/18] perf dso: Update use of pthread mutex
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To:     Ian Rogers <irogers@google.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
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        yaowenbin <yaowenbin1@huawei.com>,
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        Song Liu <songliubraving@fb.com>,
        Andrii Nakryiko <andrii@kernel.org>,
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        =?UTF-8?Q?Martin_Li=c5=a1ka?= <mliska@suse.cz>,
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        Zechuan Chen <chenzechuan1@huawei.com>,
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        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
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References: <20220824153901.488576-1-irogers@google.com>
 <20220824153901.488576-12-irogers@google.com>
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 <CAP-5=fWCpoqAhLzdMn1zHXfKpsYg0LQPMSz6Uy82+QL_MQpc8g@mail.gmail.com>
From:   Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
 Business Identity Code: 0357606 - 4, Domiciled in Helsinki
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On 26/08/22 19:05, Ian Rogers wrote:
> On Fri, Aug 26, 2022 at 3:37 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>>
>> On 24/08/22 18:38, Ian Rogers wrote:
>>> Switch to the use of mutex wrappers that provide better error checking.
>>>
>>> Signed-off-by: Ian Rogers <irogers@google.com>
>>> ---
>>>  tools/perf/util/dso.c    | 12 ++++++------
>>
>> Some not done yet
>>
>> $ grep -i pthread_mut tools/perf/util/dso.c
>> static pthread_mutex_t dso__data_open_lock = PTHREAD_MUTEX_INITIALIZER;
>>         pthread_mutex_lock(&dso__data_open_lock);
>>         pthread_mutex_unlock(&dso__data_open_lock);
>>         if (pthread_mutex_lock(&dso__data_open_lock) < 0)
>>                 pthread_mutex_unlock(&dso__data_open_lock);
>>         pthread_mutex_unlock(&dso__data_open_lock);
>>         pthread_mutex_lock(&dso__data_open_lock);
>>         pthread_mutex_unlock(&dso__data_open_lock);
>>         pthread_mutex_lock(&dso__data_open_lock);
>>         pthread_mutex_unlock(&dso__data_open_lock);
> 
> Yes, these are all solely dso__data_open_lock that lacks any clear
> init/exit code to place the initialization/destruction hooks onto. I
> don't plan to alter these in this patch set.

Perhaps that could be explained in the change log.

But why not just add init / exit code.  Could be called out
of main(), or maybe use __attribute__((constructor)) /
__attribute__((destructor))