From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756524Ab1BXWnQ (ORCPT ); Thu, 24 Feb 2011 17:43:16 -0500 Received: from e8.ny.us.ibm.com ([32.97.182.138]:39784 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755523Ab1BXWnO (ORCPT ); Thu, 24 Feb 2011 17:43:14 -0500 Subject: Re: [PATCH 8/8] Add VM counters for transparent hugepages From: Dave Hansen To: Andi Kleen Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andi Kleen , aarcange@redhat.com In-Reply-To: <1298425922-23630-9-git-send-email-andi@firstfloor.org> References: <1298425922-23630-1-git-send-email-andi@firstfloor.org> <1298425922-23630-9-git-send-email-andi@firstfloor.org> Content-Type: text/plain; charset="ISO-8859-1" Date: Thu, 24 Feb 2011 14:43:04 -0800 Message-ID: <1298587384.9138.23.camel@nimitz> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2011-02-22 at 17:52 -0800, Andi Kleen wrote: > @@ -2286,6 +2290,9 @@ void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd) > spin_unlock(&mm->page_table_lock); > return; > } > + > + count_vm_event(THP_SPLIT); > + > page = pmd_page(*pmd); > VM_BUG_ON(!page_count(page)); > get_page(page); Hey Andi, Your split counter tracks the split_huge_page_pmd() calls, but misses plain split_huge_page() calls. Did you do this on purpose? Could we move the counter in to the low-level split function like below? --- linux-2.6.git-dave/mm/huge_memory.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff -puN mm/huge_memory.c~move-THP_SPLIT mm/huge_memory.c --- linux-2.6.git/mm/huge_memory.c~move-THP_SPLIT 2011-02-24 14:37:32.825288409 -0800 +++ linux-2.6.git-dave/mm/huge_memory.c 2011-02-24 14:39:01.767939971 -0800 @@ -1342,6 +1342,8 @@ static void __split_huge_page(struct pag BUG_ON(!PageHead(page)); BUG_ON(PageTail(page)); + count_vm_event(THP_SPLIT); + mapcount = 0; list_for_each_entry(avc, &anon_vma->head, same_anon_vma) { struct vm_area_struct *vma = avc->vma; @@ -2293,8 +2295,6 @@ void __split_huge_page_pmd(struct mm_str return; } - count_vm_event(THP_SPLIT); - page = pmd_page(*pmd); VM_BUG_ON(!page_count(page)); get_page(page); -- Dave