linux-kernel - Re: [RFC PATCH 1/5] mm: memcg: make memcg huge page split support any order split.

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: <2FBD6D12-EDBE-4061-8738-E5E333F2367C@nvidia.com>
Date:   Mon, 21 Mar 2022 16:26:55 -0400
From:   Zi Yan <ziy@...dia.com>
To:     Matthew Wilcox <willy@...radead.org>
Cc:     Roman Gushchin <roman.gushchin@...ux.dev>, linux-mm@...ck.org,
        Shuah Khan <shuah@...nel.org>, Yang Shi <shy828301@...il.com>,
        Miaohe Lin <linmiaohe@...wei.com>,
        Hugh Dickins <hughd@...gle.com>,
        "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>,
        linux-kernel@...r.kernel.org, cgroups@...r.kernel.org,
        linux-kselftest@...r.kernel.org
Subject: Re: [RFC PATCH 1/5] mm: memcg: make memcg huge page split support any order split.

On 21 Mar 2022, at 15:54, Matthew Wilcox wrote:

> On Mon, Mar 21, 2022 at 03:07:46PM -0400, Zi Yan wrote:
>> Yes. Will change it to new_nr to be consistent.
>
> uh, you're going to call ilog2?

fortunately, no. Inside split_page_memcg(), I probably
need to add VM_BUG_ON(nr % new_nr != 0) to make sure
new_nr is a divisor of nr, since there are a couple
of nr / new_nr operations. Otherwise, new_nr works.

>
> I think this would look less inconsistent if 'nr' were an unsigned long
> (how long until we need 16GB pages?  Think PPC already supports those)


--
Best Regards,
Yan, Zi

Download attachment "signature.asc" of type "application/pgp-signature" (855 bytes)