From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) by kanga.kvack.org (Postfix) with ESMTP id 5A09F6B6F3F for ; Tue, 4 Dec 2018 09:49:01 -0500 (EST) Received: by mail-qt1-f197.google.com with SMTP id b26so17375824qtq.14 for ; Tue, 04 Dec 2018 06:49:01 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id n69si4278624qkn.55.2018.12.04.06.49.00 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Dec 2018 06:49:00 -0800 (PST) Date: Tue, 4 Dec 2018 09:48:55 -0500 From: Jerome Glisse Subject: Re: [PATCH 3/3] mm/mmu_notifier: contextual information for event triggering invalidation Message-ID: <20181204144854.GB3917@redhat.com> References: <20181203201817.10759-1-jglisse@redhat.com> <20181203201817.10759-4-jglisse@redhat.com> <20181204081746.GJ26700@rapoport-lnx> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20181204081746.GJ26700@rapoport-lnx> Sender: owner-linux-mm@kvack.org List-ID: To: Mike Rapoport Cc: linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, Matthew Wilcox , Ross Zwisler , Jan Kara , Dan Williams , Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Michal Hocko , Christian Koenig , Felix Kuehling , Ralph Campbell , John Hubbard , kvm@vger.kernel.org, linux-rdma@vger.kernel.org, linux-fsdevel@vger.kernel.org, dri-devel@lists.freedesktop.org On Tue, Dec 04, 2018 at 10:17:48AM +0200, Mike Rapoport wrote: > On Mon, Dec 03, 2018 at 03:18:17PM -0500, jglisse@redhat.com wrote: > > From: J�r�me Glisse [...] > > diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h > > index cbeece8e47d4..3077d487be8b 100644 > > --- a/include/linux/mmu_notifier.h > > +++ b/include/linux/mmu_notifier.h > > @@ -25,10 +25,43 @@ struct mmu_notifier_mm { > > spinlock_t lock; > > }; > > > > +/* > > + * What event is triggering the invalidation: > > Can you please make it kernel-doc comment? Sorry should have done that in the first place, Andrew i will post a v2 with that and fixing my one stupid bug. > > + * > > + * MMU_NOTIFY_UNMAP > > + * either munmap() that unmap the range or a mremap() that move the range > > + * > > + * MMU_NOTIFY_CLEAR > > + * clear page table entry (many reasons for this like madvise() or replacing > > + * a page by another one, ...). > > + * > > + * MMU_NOTIFY_PROTECTION_VMA > > + * update is due to protection change for the range ie using the vma access > > + * permission (vm_page_prot) to update the whole range is enough no need to > > + * inspect changes to the CPU page table (mprotect() syscall) > > + * > > + * MMU_NOTIFY_PROTECTION_PAGE > > + * update is due to change in read/write flag for pages in the range so to > > + * mirror those changes the user must inspect the CPU page table (from the > > + * end callback). > > + * > > + * > > + * MMU_NOTIFY_SOFT_DIRTY > > + * soft dirty accounting (still same page and same access flags) > > + */ > > +enum mmu_notifier_event { > > + MMU_NOTIFY_UNMAP = 0, > > + MMU_NOTIFY_CLEAR, > > + MMU_NOTIFY_PROTECTION_VMA, > > + MMU_NOTIFY_PROTECTION_PAGE, > > + MMU_NOTIFY_SOFT_DIRTY, > > +};