From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f69.google.com (mail-it0-f69.google.com [209.85.214.69]) by kanga.kvack.org (Postfix) with ESMTP id EAEFE6B0069 for ; Mon, 2 Jan 2017 10:55:46 -0500 (EST) Received: by mail-it0-f69.google.com with SMTP id n68so415479720itn.4 for ; Mon, 02 Jan 2017 07:55:46 -0800 (PST) Received: from smtprelay.hostedemail.com (smtprelay0217.hostedemail.com. [216.40.44.217]) by mx.google.com with ESMTPS id f127si24947406ite.15.2017.01.02.07.55.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 02 Jan 2017 07:55:27 -0800 (PST) Message-ID: <1483372522.1955.20.camel@perches.com> Subject: Re: [PATCH] mm: introduce kv[mz]alloc helpers From: Joe Perches Date: Mon, 02 Jan 2017 07:55:22 -0800 In-Reply-To: <20170102133700.1734-1-mhocko@kernel.org> References: <20170102133700.1734-1-mhocko@kernel.org> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko , Andrew Morton Cc: Vlastimil Babka , David Rientjes , Mel Gorman , Johannes Weiner , Al Viro , linux-mm@kvack.org, LKML , kvm@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org, linux-ext4@vger.kernel.org, Michal Hocko , Anatoly Stepanov , Paolo Bonzini , Mike Snitzer , "Michael S. Tsirkin" , Theodore Ts'o , Andreas Dilger On Mon, 2017-01-02 at 14:37 +0100, Michal Hocko wrote: > From: Michal Hocko > > Using kmalloc with the vmalloc fallback for larger allocations is a > common pattern in the kernel code. Yet we do not have any common helper > for that and so users have invented their own helpers. Some of them are > really creative when doing so. Let's just add kv[mz]alloc and make sure > it is implemented properly. This implementation makes sure to not make > a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also > to not warn about allocation failures. This also rules out the OOM > killer as the vmalloc is a more approapriate fallback than a disruptive > user visible action. > > This patch also changes some existing users and removes helpers which > are specific for them. In some cases this is not possible (e.g. > ext4_kvmalloc, libcfs_kvzalloc, __aa_kvmalloc) because those seems to be > broken and require GFP_NO{FS,IO} context which is not vmalloc compatible > in general (note that the page table allocation is GFP_KERNEL). Those > need to be fixed separately. > > apparmor has already claimed kv[mz]alloc so remove those and use > __aa_kvmalloc instead to prevent from the naming clashes. I have no real objection but perhaps this would be better done as 3 or more patches o rename apparmor uses o introduce generic o conversions to generic -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org