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Date:   Fri, 24 Nov 2017 13:44:29 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Vaneet Narang <v.narang@samsung.com>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        Maninder Singh <maninder1.s@samsung.com>,
        "kstewart@linuxfoundation.org" <kstewart@linuxfoundation.org>,
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Subject: Re: Re: [PATCH 1/1] stackdepot: interface to check entries and size
 of stackdepot.
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On Fri 24-11-17 11:57:07, Vaneet Narang wrote:
[...]
> > OK, so debugging a debugging facility... I do not think we want to
> > introduce a lot of code for something like that.
> 
> We enabled stackdepot on our system and realised, in long run stack depot consumes
> more runtime memory then it actually needs. we used shared patch to debug this issue. 
> stack stores following two unique entries. Page allocation done in interrupt 
> context will generate a unique stack trace. Consider following two entries.
[...]
> We have been getting similar kind of such entries and eventually
> stackdepot reaches Max Cap. So we found this interface useful in debugging
> stackdepot issue so shared in community.

Then use it for internal debugging and provide a code which would scale
better on smaller systems. We do not need this in the kernel IMHO. We do
not merge all the debugging patches we use for internal development.

-- 
Michal Hocko
SUSE Labs

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