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From:   Shakeel Butt <shakeelb@google.com>
Date:   Sat, 21 May 2022 22:42:10 -0700
Message-ID: <CALvZod7pMwN+bO5HXySiOg5k-G4s15mR0K5b_AShMdK+_DbRtg@mail.gmail.com>
Subject: Re: [PATCH v4] tracing: add 'accounted' entry into output of
 allocation tracepoints
To:     Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc:     Vasily Averin <vvs@openvz.org>,
        Andrew Morton <akpm@linux-foundation.org>, kernel@openvz.org,
        LKML <linux-kernel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>, Linux MM <linux-mm@kvack.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Vlastimil Babka <vbabka@suse.cz>,
        Matthew Wilcox <willy@infradead.org>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        David Rientjes <rientjes@google.com>,
        Pekka Enberg <penberg@kernel.org>,
        Christoph Lameter <cl@linux.com>,
        Michal Hocko <mhocko@suse.com>,
        Muchun Song <songmuchun@bytedance.com>
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On Sat, May 21, 2022 at 10:19 PM Hyeonggon Yoo <42.hyeyoo@gmail.com> wrote:
>
[...]
>
> No strong opinion but just a concern that maybe later someone want add
> something similar like 'reclaimable=true/false', 'dma=true/false', ...
> and I would prefer more general solution. (especially if we'll not
> change tracepoints after release because of backward compatibility)
>

There is no contract for tracepoints to be stable and can be changed.

> > For my task it's not important to know SLAB flags, I just need to understand,
> > is current allocation accounted or not.
>
> SLAB_ACCOUNT, SLAB_RECLAIM_ACCOUNT, SLAB_DMA, ... etc are SLAB flags.
>
> 'if current allocation is accounted or not' depends on SLAB_ACCOUNT
> flag is set or not.
>

allocation can be accounted due to __GFP_ACCOUNT as well.