From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-la0-f47.google.com (mail-la0-f47.google.com [209.85.215.47]) by kanga.kvack.org (Postfix) with ESMTP id DC6316B0069 for ; Tue, 21 Oct 2014 16:21:47 -0400 (EDT) Received: by mail-la0-f47.google.com with SMTP id pv20so1751387lab.6 for ; Tue, 21 Oct 2014 13:21:47 -0700 (PDT) Received: from gum.cmpxchg.org (gum.cmpxchg.org. [85.214.110.215]) by mx.google.com with ESMTPS id tb1si13746891lbb.130.2014.10.21.13.21.45 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 21 Oct 2014 13:21:46 -0700 (PDT) From: Johannes Weiner Subject: [patch 1/4] mm: memcontrol: inline memcg->move_lock locking Date: Tue, 21 Oct 2014 16:21:33 -0400 Message-Id: <1413922896-29042-1-git-send-email-hannes@cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Michal Hocko , Vladimir Davydov , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org The wrappers around taking and dropping the memcg->move_lock spinlock add nothing of value. Inline the spinlock calls into the callsites. Signed-off-by: Johannes Weiner --- mm/memcontrol.c | 34 +++++++++------------------------- 1 file changed, 9 insertions(+), 25 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 293db8234179..1ff125d2a427 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1507,23 +1507,6 @@ static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) return false; } -/* - * Take this lock when - * - a code tries to modify page's memcg while it's USED. - * - a code tries to modify page state accounting in a memcg. - */ -static void move_lock_mem_cgroup(struct mem_cgroup *memcg, - unsigned long *flags) -{ - spin_lock_irqsave(&memcg->move_lock, *flags); -} - -static void move_unlock_mem_cgroup(struct mem_cgroup *memcg, - unsigned long *flags) -{ - spin_unlock_irqrestore(&memcg->move_lock, *flags); -} - #define K(x) ((x) << (PAGE_SHIFT-10)) /** * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller. @@ -2013,7 +1996,7 @@ again: return; /* * If this memory cgroup is not under account moving, we don't - * need to take move_lock_mem_cgroup(). Because we already hold + * need to take &memcg->move_lock. Because we already hold * rcu_read_lock(), any calls to move_account will be delayed until * rcu_read_unlock(). */ @@ -2021,9 +2004,9 @@ again: if (atomic_read(&memcg->moving_account) <= 0) return; - move_lock_mem_cgroup(memcg, flags); + spin_lock_irqsave(&memcg->move_lock, *flags); if (memcg != pc->mem_cgroup) { - move_unlock_mem_cgroup(memcg, flags); + spin_unlock_irqrestore(&memcg->move_lock, *flags); goto again; } *locked = true; @@ -2038,7 +2021,7 @@ void __mem_cgroup_end_update_page_stat(struct page *page, unsigned long *flags) * lock is held because a routine modifies pc->mem_cgroup * should take move_lock_mem_cgroup(). */ - move_unlock_mem_cgroup(pc->mem_cgroup, flags); + spin_unlock_irqrestore(&pc->mem_cgroup->move_lock, *flags); } void mem_cgroup_update_page_stat(struct page *page, @@ -3083,7 +3066,7 @@ static int mem_cgroup_move_account(struct page *page, if (pc->mem_cgroup != from) goto out_unlock; - move_lock_mem_cgroup(from, &flags); + spin_lock_irqsave(&from->move_lock, flags); if (!PageAnon(page) && page_mapped(page)) { __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], @@ -3107,7 +3090,8 @@ static int mem_cgroup_move_account(struct page *page, /* caller should have done css_get */ pc->mem_cgroup = to; - move_unlock_mem_cgroup(from, &flags); + spin_unlock_irqrestore(&from->move_lock, flags); + ret = 0; local_irq_disable(); @@ -6033,9 +6017,9 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, * but there might still be references, e.g. from finishing * writeback. Follow the charge moving protocol here. */ - move_lock_mem_cgroup(memcg, &flags); + spin_lock_irqsave(&memcg->move_lock, flags); pc->mem_cgroup = NULL; - move_unlock_mem_cgroup(memcg, &flags); + spin_unlock_irqrestore(&memcg->move_lock, flags); if (lrucare) unlock_page_lru(oldpage, isolated); -- 2.1.2 -- 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