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Date:   Tue, 13 Mar 2018 14:18:37 -0700
From:   Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
To:     John Garry <john.garry@huawei.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>
Subject: Re: perf-core build fails on powerpc
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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. 

Thanks,

Sukadev