From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH] s390x/mm: avoid taking the table lock in gmap_pmd_op_walk() References: <20180806155407.15252-1-david@redhat.com> From: David Hildenbrand Message-ID: <85e72251-fa72-9a3f-e2b0-6bc7d9482908@redhat.com> Date: Tue, 7 Aug 2018 10:35:56 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Janosch Frank , linux-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org, Heiko Carstens , Martin Schwidefsky , Cornelia Huck , Christian Borntraeger List-ID: On 07.08.2018 09:26, Janosch Frank wrote: > On 06.08.2018 17:54, David Hildenbrand wrote: >> Right now we temporarily take the page table lock in gmap_pmd_op_walk() >> even though we know we won't need it (if we can never have 1mb pages >> mapped into the gmap). >> >> So let's special case this, so >> gmap_protect_range()/gmap_sync_dirty_log_pmd() will not take the lock in >> case huge pages are not allowed. > > So, let's make this a special case > >> >> gmap_protect_range() is called quite frequently for managing shadow >> page tables in vSIE environments. >> >> Signed-off-by: David Hildenbrand > > If you make the patch title more specific: > Reviewed-by: Janosch Frank "s390/mm: optimize locking without huge pages in gmap_pmd_op_walk()" Thanks! -- Thanks, David / dhildenb