From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx139.postini.com [74.125.245.139]) by kanga.kvack.org (Postfix) with SMTP id BA2656B004A for ; Thu, 26 Apr 2012 18:57:32 -0400 (EDT) Received: by iajr24 with SMTP id r24so241590iaj.14 for ; Thu, 26 Apr 2012 15:57:32 -0700 (PDT) Date: Thu, 26 Apr 2012 15:57:30 -0700 (PDT) From: David Rientjes Subject: [patch] mm, thp: drop page_table_lock to uncharge memcg pages Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: KAMEZAWA Hiroyuki , Andrea Arcangeli , Johannes Weiner , linux-mm@kvack.org mm->page_table_lock is hotly contested for page fault tests and isn't necessary to do mem_cgroup_uncharge_page() in do_huge_pmd_wp_page(). Signed-off-by: David Rientjes --- mm/huge_memory.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/huge_memory.c b/mm/huge_memory.c --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -968,8 +968,10 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, spin_lock(&mm->page_table_lock); put_page(page); if (unlikely(!pmd_same(*pmd, orig_pmd))) { + spin_unlock(&mm->page_table_lock); mem_cgroup_uncharge_page(new_page); put_page(new_page); + goto out; } else { pmd_t entry; VM_BUG_ON(!PageHead(page)); -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org