From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932541AbcGDDXS (ORCPT ); Sun, 3 Jul 2016 23:23:18 -0400 Received: from mail-pf0-f194.google.com ([209.85.192.194]:35075 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932319AbcGDDXQ (ORCPT ); Sun, 3 Jul 2016 23:23:16 -0400 Date: Mon, 4 Jul 2016 11:23:10 +0800 From: Ganesh Mahendran To: Minchan Kim Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, ngupta@vflare.org, sergey.senozhatsky.work@gmail.com, rostedt@goodmis.org, mingo@redhat.com Subject: Re: [PATCH 3/8] mm/zsmalloc: take obj index back from find_alloced_obj Message-ID: <20160704032310.GB9895@leo-test> References: <1467355266-9735-1-git-send-email-opensource.ganesh@gmail.com> <1467355266-9735-3-git-send-email-opensource.ganesh@gmail.com> <20160703235704.GB19044@bbox> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160703235704.GB19044@bbox> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 04, 2016 at 08:57:04AM +0900, Minchan Kim wrote: > On Fri, Jul 01, 2016 at 02:41:01PM +0800, Ganesh Mahendran wrote: > > the obj index value should be updated after return from > > find_alloced_obj() > > to avoid CPU buring caused by unnecessary object scanning. > > Description should include what's the goal. Thanks for your reminder. > > > > > Signed-off-by: Ganesh Mahendran > > --- > > mm/zsmalloc.c | 13 ++++++++----- > > 1 file changed, 8 insertions(+), 5 deletions(-) > > > > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > > index 405baa5..5c96ed1 100644 > > --- a/mm/zsmalloc.c > > +++ b/mm/zsmalloc.c > > @@ -1744,15 +1744,16 @@ static void zs_object_copy(struct size_class *class, unsigned long dst, > > * return handle. > > */ > > static unsigned long find_alloced_obj(struct size_class *class, > > - struct page *page, int index) > > + struct page *page, int *index) > > { > > unsigned long head; > > int offset = 0; > > + int objidx = *index; > > Nit: > > We have used obj_idx so I prefer it for consistency with others. will do it. > > Suggestion: > Could you mind changing index in zs_compact_control and > migrate_zspage with obj_idx in this chance? I will add a clean up patch in this patchset. > > Strictly speaking, such clean up is separate patch but I don't mind > mixing them here(Of course, you will send it as another clean up patch, > it would be better). If you mind, just let it leave as is. Sometime, > I wil do it. > > > unsigned long handle = 0; > > void *addr = kmap_atomic(page); > > > > offset = get_first_obj_offset(page); > > - offset += class->size * index; > > + offset += class->size * objidx; > > > > while (offset < PAGE_SIZE) { > > head = obj_to_head(page, addr + offset); > > @@ -1764,9 +1765,11 @@ static unsigned long find_alloced_obj(struct size_class *class, > > } > > > > offset += class->size; > > - index++; > > + objidx++; > > } > > > > + *index = objidx; > > We can do this out of kmap section right before returing handle. That's right. I will send a V2 patch soon. Thanks. > > Thanks! > > > + > > kunmap_atomic(addr); > > return handle; > > } > > @@ -1794,11 +1797,11 @@ static int migrate_zspage(struct zs_pool *pool, struct size_class *class, > > unsigned long handle; > > struct page *s_page = cc->s_page; > > struct page *d_page = cc->d_page; > > - unsigned long index = cc->index; > > + unsigned int index = cc->index; > > int ret = 0; > > > > while (1) { > > - handle = find_alloced_obj(class, s_page, index); > > + handle = find_alloced_obj(class, s_page, &index); > > if (!handle) { > > s_page = get_next_page(s_page); > > if (!s_page) > > -- > > 1.9.1 > >