From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f169.google.com (mail-pf0-f169.google.com [209.85.192.169]) by kanga.kvack.org (Postfix) with ESMTP id EAD176B0256 for ; Wed, 23 Dec 2015 17:26:23 -0500 (EST) Received: by mail-pf0-f169.google.com with SMTP id e65so6007821pfe.1 for ; Wed, 23 Dec 2015 14:26:23 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id bm5si12737045pad.107.2015.12.23.14.26.23 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 23 Dec 2015 14:26:23 -0800 (PST) Date: Wed, 23 Dec 2015 14:26:11 -0800 From: Andrew Morton Subject: Re: [Intel-gfx] [PATCH v2 1/2] mm: Export nr_swap_pages Message-Id: <20151223142611.63907890.akpm@linux-foundation.org> In-Reply-To: <20151223220427.GA11412@cmpxchg.org> References: <1449244734-25733-1-git-send-email-chris@chris-wilson.co.uk> <20151204160952.GA24927@cmpxchg.org> <20151210093242.GH20822@phenom.ffwll.local> <20151223220427.GA11412@cmpxchg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Daniel Vetter , Chris Wilson , linux-mm@kvack.org, intel-gfx@lists.freedesktop.org, "Goel, Akash" On Wed, 23 Dec 2015 17:04:27 -0500 Johannes Weiner wrote: > On Thu, Dec 10, 2015 at 10:32:42AM +0100, Daniel Vetter wrote: > > On Fri, Dec 04, 2015 at 11:09:52AM -0500, Johannes Weiner wrote: > > > On Fri, Dec 04, 2015 at 03:58:53PM +0000, Chris Wilson wrote: > > > > Some modules, like i915.ko, use swappable objects and may try to swap > > > > them out under memory pressure (via the shrinker). Before doing so, they > > > > want to check using get_nr_swap_pages() to see if any swap space is > > > > available as otherwise they will waste time purging the object from the > > > > device without recovering any memory for the system. This requires the > > > > nr_swap_pages counter to be exported to the modules. > > > > > > > > Signed-off-by: Chris Wilson > > > > Cc: "Goel, Akash" > > > > Cc: Johannes Weiner > > > > Cc: linux-mm@kvack.org > > > > > > Acked-by: Johannes Weiner > > > > Ack for merging this through drm-intel trees for 4.5? I'm a bit unclear > > who's ack I need for that for linux-mm topics ... > > Andrew would be the -mm maintainer. CC'd. yup, please go ahead and merge that via the DRM tree. nr_swap_pages is a crappy name. That means "number of pages in swap", which isn't the case. Something like "swap_pages_available" would be better. And your swap_available() isn't good either ;) It can mean "is any swap online" or "what is the amount of free swap space (in unknown units!)". I'd call it "swap_is_full()" and put a ! in the caller. But it's hardly important for a wee little static helper. -- 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