From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 68DF86B007D for ; Mon, 11 Jan 2010 22:03:35 -0500 (EST) Date: Tue, 12 Jan 2010 11:03:30 +0800 From: Wu Fengguang Subject: Re: [PATCH 4/4] mm/page_alloc : relieve zone->lock's pressure for memory free Message-ID: <20100112030330.GA20034@localhost> References: <1263184634-15447-4-git-send-email-shijie8@gmail.com> <1263264697-1598-1-git-send-email-shijie8@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1263264697-1598-1-git-send-email-shijie8@gmail.com> Sender: owner-linux-mm@kvack.org To: Huang Shijie Cc: "akpm@linux-foundation.org" , "mel@csn.ul.ie" , "kosaki.motohiro@jp.fujitsu.com" , "kamezawa.hiroyu@jp.fujitsu.com" , "minchan.kim@gmail.com" , "linux-mm@kvack.org" , "riel@redhat.com" List-ID: Hi Shijie, > + int free_ok; > > - __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order); > - __free_one_page(page, zone, order, migratetype); > + spin_lock(&zone->lock); > + free_ok = __free_one_page(page, zone, order, migratetype); > spin_unlock(&zone->lock); > + > + if (likely(free_ok)) { > + zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); > + zone->pages_scanned = 0; > + __mod_zone_page_state(zone, NR_FREE_PAGES, free_ok << order); > + } If we do __mod_zone_page_state(zone, -NR_FREE_PAGES, count); in __free_one_page() on error, we can remove the likely(free_ok) test. This sounds a bit hacky though. Thanks, Fengguang -- 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