From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f69.google.com (mail-pg0-f69.google.com [74.125.83.69]) by kanga.kvack.org (Postfix) with ESMTP id 234196B0279 for ; Thu, 8 Jun 2017 21:58:54 -0400 (EDT) Received: by mail-pg0-f69.google.com with SMTP id m19so21422709pgd.14 for ; Thu, 08 Jun 2017 18:58:54 -0700 (PDT) Received: from szxga02-in.huawei.com (szxga02-in.huawei.com. [45.249.212.188]) by mx.google.com with ESMTPS id f4si5696502plb.101.2017.06.08.18.58.52 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 08 Jun 2017 18:58:53 -0700 (PDT) Message-ID: <593A0080.4040806@huawei.com> Date: Fri, 9 Jun 2017 09:57:20 +0800 From: zhong jiang MIME-Version: 1.0 Subject: Re: [PATCH] mm: correct the comment when reclaimed pages exceed the scanned pages References: <1496824266-25235-1-git-send-email-zhongjiang@huawei.com> <20170608064658.GA9190@bbox> In-Reply-To: <20170608064658.GA9190@bbox> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim , akpm@linux-foundation.org Cc: vinayakm.list@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org On 2017/6/8 14:46, Minchan Kim wrote: > On Wed, Jun 07, 2017 at 04:31:06PM +0800, zhongjiang wrote: >> The commit e1587a494540 ("mm: vmpressure: fix sending wrong events on >> underflow") declare that reclaimed pages exceed the scanned pages due >> to the thp reclaim. it is incorrect because THP will be spilt to normal >> page and loop again. which will result in the scanned pages increment. >> >> Signed-off-by: zhongjiang >> --- >> mm/vmpressure.c | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/mm/vmpressure.c b/mm/vmpressure.c >> index 6063581..0e91ba3 100644 >> --- a/mm/vmpressure.c >> +++ b/mm/vmpressure.c >> @@ -116,8 +116,9 @@ static enum vmpressure_levels vmpressure_calc_level(unsigned long scanned, >> >> /* >> * reclaimed can be greater than scanned in cases >> - * like THP, where the scanned is 1 and reclaimed >> - * could be 512 >> + * like reclaimed slab pages, shrink_node just add >> + * reclaimed page without a related increment to >> + * scanned pages. >> */ >> if (reclaimed >= scanned) >> goto out; > Thanks for the fixing my fault! > > Acked-by: Minchan Kim > > Frankly speaking, I'm not sure we need such comment in there at the cost > of maintainance because it would be fragile but easy to fix by above simple > condition so I think it would be better to remove that comment but others > might be different. So, don't have any objection. > > > . > Thanks Regards zhongjiang -- 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/ . Don't email: email@kvack.org