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Date:   Sun, 8 Sep 2019 22:28:32 +0900
From:   Namhyung Kim <namhyung@kernel.org>
To:     Tejun Heo <tj@kernel.org>
Cc:     Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Jiri Olsa <jolsa@redhat.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Stephane Eranian <eranian@google.com>,
        Li Zefan <lizefan@huawei.com>,
        Johannes Weiner <hannes@cmpxchg.org>
Subject: Re: [PATCH 2/9] perf/core: Add PERF_SAMPLE_CGROUP feature
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Hi Tejun,

On Thu, Sep 05, 2019 at 09:56:55AM -0700, Tejun Heo wrote:
> Hello, Namhyung.
> 
> On Tue, Sep 03, 2019 at 10:13:08AM +0800, Namhyung Kim wrote:
> > So is my understanding below correct?
> > 
> >  * currently kernfs ino+gen is different than inode's ino+gen
> 
> They're the same.  It's just that cgroup has other less useful IDs
> too.

Ah, ok.

> 
> >  * but it'd be better to make them same
> >  * so move (generic?) inode's ino+gen logic to cgroup
> >  * and kernfs node use the same logic (and number)
> >  * so perf sampling code (NMI) just access kernfs node
> >  * and userspace can use file handle for comparison
> 
> The rest, yes, pretty much.

Thanks for the clarification.  I'll take a look at it.

Thanks
Namhyung