From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mel Gorman Subject: Re: [PATCH 06/10] vmscan: Split shrink_zone to reduce stack usage Date: Fri, 16 Apr 2010 15:27:25 +0100 Message-ID: <20100416142725.GE19264@csn.ul.ie> References: <1271352103-2280-1-git-send-email-mel@csn.ul.ie> <1271352103-2280-7-git-send-email-mel@csn.ul.ie> <20100416042308.GZ2493@dastard> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Mason , KOSAKI Motohiro , Andi Kleen , Johannes Weiner To: Dave Chinner Return-path: Content-Disposition: inline In-Reply-To: <20100416042308.GZ2493@dastard> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Apr 16, 2010 at 02:23:08PM +1000, Dave Chinner wrote: > On Thu, Apr 15, 2010 at 06:21:39PM +0100, Mel Gorman wrote: > > shrink_zone() calculculates how many pages it needs to shrink from each > > LRU list in a given pass. It uses a number of temporary variables to > > work this out that then remain on the stack. This patch splits the > > function so that some of the stack variables can be discarded. > > > > Signed-off-by: Mel Gorman > > --- > > mm/vmscan.c | 29 +++++++++++++++++++---------- > > 1 files changed, 19 insertions(+), 10 deletions(-) > > > > diff --git a/mm/vmscan.c b/mm/vmscan.c > > index 1ace7c6..a374879 100644 > > --- a/mm/vmscan.c > > +++ b/mm/vmscan.c > > @@ -1595,19 +1595,14 @@ static unsigned long nr_scan_try_batch(unsigned long nr_to_scan, > > return nr; > > } > > > > -/* > > - * This is a basic per-zone page freer. Used by both kswapd and direct reclaim. > > - */ > > -static void shrink_zone(struct zone *zone, struct scan_control *sc) > > +/* Calculate how many pages from each LRU list should be scanned */ > > +static void calc_scan_trybatch(struct zone *zone, > > + struct scan_control *sc, unsigned long *nr) > > Needs "noinline_for_stack" to stop the compiler re-inlining it. > Agreed. I was using noinline where I spotted the compiler automatically inlined but noinline_for_stack both handles future compiler changes and is self-documenting. Thanks -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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