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Subject: Re: perf-core build fails on powerpc
To:     Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
References: <20180313191742.GA29120@us.ibm.com>
 <152d2ba4-fe57-beab-87d5-554a0fede9ae@huawei.com>
 <20180313201003.GB29120@us.ibm.com>
 <543acf58-520d-e3e2-211e-17068d713a4f@huawei.com>
 <20180313211837.GC29120@us.ibm.com>
CC:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        <linux-kernel@vger.kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        "Jiri Olsa" <jolsa@redhat.com>
From:   John Garry <john.garry@huawei.com>
Message-ID: <603efe46-6b79-3066-751e-696502eaef3f@huawei.com>
Date:   Wed, 14 Mar 2018 07:10:53 +0000
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On 13/03/2018 21:18, Sukadev Bhattiprolu wrote:
> John Garry [john.garry@huawei.com] wrote:
>> On 13/03/2018 20:10, Sukadev Bhattiprolu wrote:
>>
>>> Hi John,
>>>
>>> I have an xfs file system which seems to have d_type == DT_UNKNOWN for all
>>> entries in 'tools/perf/pmu-events/arch/power8'! readdir(3) says ->d_type
>>> may not be supported by all file systems.
>>>
>>> Not relying on ->d_type seems to fix it:
>>>
>>
>> Hi Sukadev,
>>
>> Thanks for debugging this. Jiri Olsa (cc'ed) warned me on this, so I did add
>> the check for d_type == DT_UNKNOWN.
>>
>> But, if all files have d_type == DT_UNKNOWN, you're code would from visual
>> observation look to be same as mine (apart from check for '.' or '..'
>> filename, which I would say is already covered by stat() and S_ISDIR()). Or
>> is d_type value just unreliable?
>
> In the current code and with DT_UNKNOWN, is_leaf_dir() returns false when
> it sees the "." or ".." entries right? In the new code, we skip those and
> return false only if we find some other directory.
>

OK, that's the real issue, being the "." and ".." entries.

@Arnaldo, I'll try to send a fix for this today. I just need to make an 
xfs to test. Sorry for the hassle.

John

> Thanks,
>
> Sukadev
>
>
>