From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751004AbbCTFzz (ORCPT ); Fri, 20 Mar 2015 01:55:55 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:36290 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750756AbbCTFzx (ORCPT ); Fri, 20 Mar 2015 01:55:53 -0400 Date: Fri, 20 Mar 2015 14:55:59 +0900 From: Sergey Senozhatsky To: Yinghao Xie Cc: Andrew Morton , Minchan Kim , Nitin Gupta , mm , lkml , sergey.senozhatsky@gmail.com Subject: Re: mm/zsmalloc.c: count in handle's size when calculating pages_per_zspage Message-ID: <20150320055559.GA23604@swordfish> References: <430707086.362221426765159948.JavaMail.weblogic@epmlwas05d> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <430707086.362221426765159948.JavaMail.weblogic@epmlwas05d> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, sorry, I've a question. On (03/19/15 11:39), Yinghao Xie wrote: > @@ -1426,11 +1430,6 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size) > /* extra space in chunk to keep the handle */ > size += ZS_HANDLE_SIZE; > class = pool->size_class[get_size_class_index(size)]; > - /* In huge class size, we store the handle into first_page->private */ > - if (class->huge) { > - size -= ZS_HANDLE_SIZE; > - class = pool->size_class[get_size_class_index(size)]; > - } if huge class uses page->private to store a handle, shouldn't we pass "size -= ZS_HANDLE_SIZE" to get_size_class_index() ? -ss > spin_lock(&class->lock); > first_page = find_get_zspage(class); > @@ -1856,9 +1855,7 @@ struct zs_pool *zs_create_pool(char *name, gfp_t flags) > struct size_class *class; > > size = ZS_MIN_ALLOC_SIZE + i * ZS_SIZE_CLASS_DELTA; > - if (size > ZS_MAX_ALLOC_SIZE) > - size = ZS_MAX_ALLOC_SIZE; > - pages_per_zspage = get_pages_per_zspage(size); > + pages_per_zspage = get_pages_per_zspage(size + ZS_HANDLE_SIZE); > > /* > * size_class is used for normal zsmalloc operation such