Re: perf-core build fails on powerpc

From: Sukadev Bhattiprolu
Date: Tue Mar 13 2018 - 17:18:49 EST


John Garry [john.garry@xxxxxxxxxx] 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