From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752759AbcGFGX7 (ORCPT <rfc822;w@1wt.eu>);
	Wed, 6 Jul 2016 02:23:59 -0400
Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:14592 "EHLO
	mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK)
	by vger.kernel.org with ESMTP id S1751263AbcGFGX5 (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 6 Jul 2016 02:23:57 -0400
X-IBM-Helo: d06dlp02.portsmouth.uk.ibm.com
X-IBM-MailFrom: schwidefsky@de.ibm.com
X-IBM-RcptTo: linux-kernel@vger.kernel.org
Date: Wed, 6 Jul 2016 08:23:50 +0200
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: "Hillf Danton" <hillf.zj@alibaba-inc.com>
Cc: "linux-kernel" <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>
Subject: Re: [PATCH 2/2] s390/mm: use ipte range to invalidate multiple page
 table entries
In-Reply-To: <014601d1d73b$5a3c0420$0eb40c60$@alibaba-inc.com>
References: <014201d1d738$744c8f90$5ce5aeb0$@alibaba-inc.com>
	<014601d1d73b$5a3c0420$0eb40c60$@alibaba-inc.com>
X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-pc-linux-gnu)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
X-TM-AS-MML: disable
X-Content-Scanned: Fidelis XPS MAILER
x-cbid: 16070606-0024-0000-0000-00000226EA63
X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused
x-cbparentid: 16070606-0025-0000-0000-000019620027
Message-Id: <20160706082350.5c56ca40@mschwide>
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-07-06_03:,,
 signatures=0
X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0
 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam
 adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000
 definitions=main-1607060058
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Wed, 06 Jul 2016 12:03:28 +0800
"Hillf Danton" <hillf.zj@alibaba-inc.com> wrote:

> > 
> > +void ptep_invalidate_range(struct mm_struct *mm, unsigned long start,
> > +			   unsigned long end, pte_t *ptep)
> > +{
> > +	unsigned long nr;
> > +
> > +	if (!MACHINE_HAS_IPTE_RANGE || mm_has_pgste(mm))
> > +		return;
> > +	preempt_disable();
> > +	nr = (end - start) >> PAGE_SHIFT;
> > +	/* If the flush is likely to be local skip the ipte range */
> > +	if (nr && !cpumask_equal(mm_cpumask(mm),
> > +				 cpumask_of(smp_processor_id())))
> 
> s/smp/raw_smp/ to avoid adding schedule entry with page table
> lock held?

There can not be a schedule entry with either the page table lock held
or the preempt_disable() a few lines above.
 
> > +		__ptep_ipte_range(start, nr - 1, ptep);
> > +	preempt_enable();
> > +}
> > +EXPORT_SYMBOL(ptep_invalidate_range);
> > +
> 
> thanks
> Hillf
> 


-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.