Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751829Ab0HBKY7 (ORCPT ); Mon, 2 Aug 2010 06:24:59 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:41212 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751152Ab0HBKY5 (ORCPT ); Mon, 2 Aug 2010 06:24:57 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Mon, 2 Aug 2010 19:20:06 +0900 From: KAMEZAWA Hiroyuki To: KAMEZAWA Hiroyuki Cc: linux-mm@kvack.org, "balbir@linux.vnet.ibm.com" , "nishimura@mxp.nes.nec.co.jp" , vgoyal@redhat.com, m-ikeda@ds.jp.nec.com, gthelen@google.com, "akpm@linux-foundation.org" , "linux-kernel@vger.kernel.org" Subject: [PATCH -mm 5/5] memcg: use spinlock in page_cgroup instead of bit_spinlock Message-Id: <20100802192006.a395889a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100802191113.05c982e4.kamezawa.hiroyu@jp.fujitsu.com> References: <20100802191113.05c982e4.kamezawa.hiroyu@jp.fujitsu.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4001 Lines: 133 From: KAMEZAWA Hiroyuki This patch replaces bit_spinlock with spinlock. In general, spinlock has good functinality 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. expected effects: - use better codes. - ticket lock on x86-64 - para-vitualization aware lock etc.. Chagelog: 20090729 - fixed page_cgroup_is_locked(). Signed-off-by: KAMEZAWA Hiroyuki -- --- include/linux/page_cgroup.h | 33 ++++++++++++++++++++++++++++++++- mm/memcontrol.c | 2 +- mm/page_cgroup.c | 3 +++ 3 files changed, 36 insertions(+), 2 deletions(-) Index: mmotm-0727/include/linux/page_cgroup.h =================================================================== --- mmotm-0727.orig/include/linux/page_cgroup.h +++ mmotm-0727/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; @@ -36,7 +42,9 @@ struct page_cgroup *lookup_page_cgroup(s enum { /* flags for mem_cgroup */ - PCG_LOCK, /* page cgroup is locked */ +#ifndef PCG_HAS_SPINLOCK + PCG_LOCK, /* page cgroup is locked (see below also.)*/ +#endif PCG_CACHE, /* charged as cache */ PCG_USED, /* this object is in use. */ PCG_ACCT_LRU, /* page has been accounted for */ @@ -65,8 +73,6 @@ static inline void ClearPageCgroup##unam static inline int TestClearPageCgroup##uname(struct page_cgroup *pc) \ { return test_and_clear_bit(PCG_##lname, &pc->flags); } -TESTPCGFLAG(Locked, LOCK) - /* Cache flag is set only once (at allocation) */ TESTPCGFLAG(Cache, CACHE) CLEARPCGFLAG(Cache, CACHE) @@ -95,6 +101,22 @@ 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); +} + +static inline bool page_cgroup_is_locked(struct page_cgroup *pc) +{ + return spin_is_locked(&pc->lock); +} + +#else static inline void lock_page_cgroup(struct page_cgroup *pc) { bit_spin_lock(PCG_LOCK, &pc->flags); @@ -105,6 +127,14 @@ static inline void unlock_page_cgroup(st bit_spin_unlock(PCG_LOCK, &pc->flags); } +static inline void page_cgroup_is_locked(struct page_cgrou *pc) +{ + bit_spin_is_locked(PCG_LOCK, &pc->flags); +} +TESTPCGFLAG(Locked, LOCK) + +#endif + #else /* CONFIG_CGROUP_MEM_RES_CTLR */ struct page_cgroup; Index: mmotm-0727/mm/page_cgroup.c =================================================================== --- mmotm-0727.orig/mm/page_cgroup.c +++ mmotm-0727/mm/page_cgroup.c @@ -18,6 +18,9 @@ __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; Index: mmotm-0727/mm/memcontrol.c =================================================================== --- mmotm-0727.orig/mm/memcontrol.c +++ mmotm-0727/mm/memcontrol.c @@ -1999,7 +1999,7 @@ static void __mem_cgroup_move_account(st int i; VM_BUG_ON(from == to); VM_BUG_ON(PageLRU(pc->page)); - VM_BUG_ON(!PageCgroupLocked(pc)); + VM_BUG_ON(!page_cgroup_is_locked(pc)); VM_BUG_ON(!PageCgroupUsed(pc)); VM_BUG_ON(id_to_memcg(pc->mem_cgroup) != from); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/