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Message-ID: <0c73ce5c-3625-6187-820e-1277e168b3bc@openvz.org>
Date:   Sat, 21 May 2022 21:32:11 +0300
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Subject: Re: [PATCH v3] tracing: add 'accounted' entry into output of
 allocation tracepoints
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To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     YoPOhRctb8wwbmY5@carbon, Shakeel Butt <shakeelb@google.com>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Vlastimil Babka <vbabka@suse.cz>,
        Matthew Wilcox <willy@infradead.org>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Muchun Song <songmuchun@bytedance.com>, kernel@openvz.org,
        linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.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>
References: <f6625cd8-90f9-6d48-50f6-7bb052bf479f@openvz.org>
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 <20220519123255.543b8db6@gandalf.local.home>
From:   Vasily Averin <vvs@openvz.org>
In-Reply-To: <20220519123255.543b8db6@gandalf.local.home>
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On 5/19/22 19:32, Steven Rostedt wrote:
> On Thu, 19 May 2022 19:29:36 +0300
> Vasily Averin <vvs@openvz.org> wrote:
> 
>> Frankly speaking I vote for performance with both hands.
>> However I'm still would like to avoid new sparse warnings.
>> Christoph Hellwig just recently taught me, "never add '__force' before
>> thinking hard about them", but in this case I would need to use it three times.
>>
>> I found that bitwise typecasts can be avoided by using translation unions. 
>>
>> What do you think about following trick?
> 
> It's really up to you memory management folks. Although I may need to
> update libtraceevent to handle the union case. That may be a bit tricky.

In this case, I would like to keep sub-optimal v3 patch version.
If necessary, we can improve the performance later, and right now
I will send v4 with minor patch description changes and ask
Andrew Morton to include it in the mm tree.

Thank you,
	Vasily Averin