linux-kernel - Re: [PATCH 2/8] mm, page_alloc: set alloc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <49843a12-3b00-06f5-8645-098e875ec075@suse.cz>
Date:	Thu, 21 Jul 2016 09:00:46 +0200
From:	Vlastimil Babka <vbabka@...e.cz>
To:	David Rientjes <rientjes@...gle.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org, Michal Hocko <mhocko@...nel.org>,
	Mel Gorman <mgorman@...hsingularity.net>,
	Joonsoo Kim <iamjoonsoo.kim@....com>,
	Rik van Riel <riel@...hat.com>
Subject: Re: [PATCH 2/8] mm, page_alloc: set alloc_flags only once in slowpath

On 07/20/2016 12:28 AM, David Rientjes wrote:
> On Mon, 18 Jul 2016, Vlastimil Babka wrote:
>
>> In __alloc_pages_slowpath(), alloc_flags doesn't change after it's initialized,
>> so move the initialization above the retry: label. Also make the comment above
>> the initialization more descriptive.
>>
>> The only exception in the alloc_flags being constant is ALLOC_NO_WATERMARKS,
>> which may change due to TIF_MEMDIE being set on the allocating thread. We can
>> fix this, and make the code simpler and a bit more effective at the same time,
>> by moving the part that determines ALLOC_NO_WATERMARKS from
>> gfp_to_alloc_flags() to gfp_pfmemalloc_allowed(). This means we don't have to
>> mask out ALLOC_NO_WATERMARKS in numerous places in __alloc_pages_slowpath()
>> anymore. The only two tests for the flag can instead call
>> gfp_pfmemalloc_allowed().
>>
>> Signed-off-by: Vlastimil Babka <vbabka@...e.cz>
>
> Acked-by: David Rientjes <rientjes@...gle.com>
>
> Looks good, although maybe a new name for gfp_pfmemalloc_allowed() would
> be in order.

I don't disagree... any good suggestions? :)