Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753351AbaJWXb6 (ORCPT ); Thu, 23 Oct 2014 19:31:58 -0400 Received: from lgeamrelo04.lge.com ([156.147.1.127]:63210 "EHLO lgeamrelo04.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751573AbaJWXb5 (ORCPT ); Thu, 23 Oct 2014 19:31:57 -0400 X-Original-SENDERIP: 10.186.123.76 X-Original-MAILFROM: gioh.kim@lge.com Message-ID: <54498FE8.4010700@lge.com> Date: Fri, 24 Oct 2014 08:31:52 +0900 From: Gioh Kim User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Devendra Naga CC: Greg Kroah-Hartman , John Stultz , Rebecca Schultz Zavin , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, gunho.lee@lge.com Subject: Re: [RFC 1/2] staging: ion: shrink page-pool by page unit References: <1414068740-9553-1-git-send-email-gioh.kim@lge.com> <1414068740-9553-2-git-send-email-gioh.kim@lge.com> <54498C68.8090207@lge.com> In-Reply-To: <54498C68.8090207@lge.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2014-10-24 오전 8:16, Gioh Kim 쓴 글: > > > 2014-10-24 오전 5:36, Devendra Naga 쓴 글: >> Hello, >> >> On Thu, Oct 23, 2014 at 6:22 PM, Gioh Kim wrote: >>> This patch shrink page-pool by page unit. >>> >>> Signed-off-by: Gioh Kim >>> --- >>> drivers/staging/android/ion/ion_page_pool.c | 5 +++-- >>> drivers/staging/android/ion/ion_system_heap.c | 7 +++++-- >>> 2 files changed, 8 insertions(+), 4 deletions(-) >> >>> >> >> --- cut -- >> >>> diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c >>> index da2a63c..36e73c3 100644 >>> --- a/drivers/staging/android/ion/ion_system_heap.c >>> +++ b/drivers/staging/android/ion/ion_system_heap.c >>> @@ -211,7 +211,7 @@ static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask, >>> int nr_to_scan) >>> { >>> struct ion_system_heap *sys_heap; >>> - int nr_total = 0; >>> + int nr_total = 0, nr_freed; >>> int i; >>> >>> sys_heap = container_of(heap, struct ion_system_heap, heap); >>> @@ -219,7 +219,10 @@ static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask, >>> for (i = 0; i < num_orders; i++) { >>> struct ion_page_pool *pool = sys_heap->pools[i]; >>> >>> - nr_total += ion_page_pool_shrink(pool, gfp_mask, nr_to_scan); >>> + nr_freed += ion_page_pool_shrink(pool, gfp_mask, nr_to_scan); >> >> nr_freed is not initialised to zero. This might result in updating of >> a garbage value stored initially after nr_freed is created. > > Yes, your're right. It's my mistake. > I testes this on my platform with custom kernel and copied codes. > I missed a line for it. > I'm sorry. Following is the correct code: nr_freed = ion_page_pool_shrink(pool, gfp_mask, nr_to_scan); > >> >>> + nr_total += nr_freed; >>> + /* nr_to_scan can be negative */ >>> + nr_to_scan -= nr_freed; >>> } >>> >>> return nr_total; >>> -- >>> 1.7.9.5 >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> Please read the FAQ at http://www.tux.org/lkml/ >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/