From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 4D18A600365 for ; Tue, 27 Jul 2010 04:07:00 -0400 (EDT) Received: from m2.gw.fujitsu.co.jp ([10.0.50.72]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o6R87DZn010769 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Tue, 27 Jul 2010 17:07:13 +0900 Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 2E21245DE57 for ; Tue, 27 Jul 2010 17:07:13 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 0B81B45DE4F for ; Tue, 27 Jul 2010 17:07:13 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id C95D31DB803C for ; Tue, 27 Jul 2010 17:07:12 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 861A41DB803A for ; Tue, 27 Jul 2010 17:07:12 +0900 (JST) Date: Tue, 27 Jul 2010 17:02:25 +0900 From: KAMEZAWA Hiroyuki Subject: [RFC][PATCH 7/7][memcg] use spin lock instead of bit_spin_lock in page_cgroup Message-Id: <20100727170225.64f78b15.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100727165155.8b458b7f.kamezawa.hiroyu@jp.fujitsu.com> References: <20100727165155.8b458b7f.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "nishimura@mxp.nes.nec.co.jp" , "balbir@linux.vnet.ibm.com" , gthelen@google.com, m-ikeda@ds.jp.nec.com, "akpm@linux-foundation.org" , "linux-kernel@vger.kernel.org" List-ID: From: KAMEZAWA Hiroyuki This patch replaces page_cgroup's bit_spinlock with spinlock. In general, spinlock has good implementation than bit_spin_lock and we should use it if we have a room for it. In 64bit arch, we have extra 4bytes. Let's use it. Signed-off-by: KAMEZAWA Hiroyuki -- Index: mmotm-0719/include/linux/page_cgroup.h =================================================================== --- mmotm-0719.orig/include/linux/page_cgroup.h +++ mmotm-0719/include/linux/page_cgroup.h @@ -10,8 +10,14 @@ * All page cgroups are allocated at boot or memory hotplug event, * then the page cgroup for pfn always exists. */ +#ifdef CONFIG_64BIT +#define PCG_HAS_SPINLOCK +#endif struct page_cgroup { unsigned long flags; +#ifdef PCG_HAS_SPINLOCK + spinlock_t lock; +#endif unsigned short mem_cgroup; /* ID of assigned memory cgroup */ unsigned short blk_cgroup; /* Not Used..but will be. */ struct page *page; @@ -90,6 +96,16 @@ static inline enum zone_type page_cgroup return page_zonenum(pc->page); } +#ifdef PCG_HAS_SPINLOCK +static inline void lock_page_cgroup(struct page_cgroup *pc) +{ + spin_lock(&pc->lock); +} +static inline void unlock_page_cgroup(struct page_cgroup *pc) +{ + spin_unlock(&pc->lock); +} +#else static inline void lock_page_cgroup(struct page_cgroup *pc) { bit_spin_lock(PCG_LOCK, &pc->flags); @@ -99,6 +115,7 @@ static inline void unlock_page_cgroup(st { bit_spin_unlock(PCG_LOCK, &pc->flags); } +#endif static inline void SetPCGFileFlag(struct page_cgroup *pc, int idx) { Index: mmotm-0719/mm/page_cgroup.c =================================================================== --- mmotm-0719.orig/mm/page_cgroup.c +++ mmotm-0719/mm/page_cgroup.c @@ -17,6 +17,9 @@ __init_page_cgroup(struct page_cgroup *p pc->mem_cgroup = 0; pc->page = pfn_to_page(pfn); INIT_LIST_HEAD(&pc->lru); +#ifdef PCG_HAS_SPINLOCK + spin_lock_init(&pc->lock); +#endif } static unsigned long total_usage; -- 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