Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933594AbaGQOM2 (ORCPT ); Thu, 17 Jul 2014 10:12:28 -0400 Received: from mail-qc0-f169.google.com ([209.85.216.169]:41763 "EHLO mail-qc0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932139AbaGQOM0 (ORCPT ); Thu, 17 Jul 2014 10:12:26 -0400 Date: Thu, 17 Jul 2014 10:12:18 -0400 From: Jerome Glisse To: Oded Gabbay Cc: David Airlie , Alex Deucher , Andrew Morton , John Bridgman , Joerg Roedel , Andrew Lewycky , Christian =?iso-8859-1?Q?K=F6nig?= , Michel =?iso-8859-1?Q?D=E4nzer?= , Ben Goz , Alexey Skidanov , Evgeny Pinchuk , "Kirill A. Shutemov" , Rik van Riel , Peter Zijlstra , Mel Gorman , Joonsoo Kim , =?iso-8859-1?B?Suly9G1l?= Glisse , linux-kernel@vger.kernel.org, linux-mm Subject: Re: [PATCH v2 01/25] mm: Add kfd_process pointer to mm_struct Message-ID: <20140717141216.GA1963@gmail.com> References: <1405603773-32688-1-git-send-email-oded.gabbay@amd.com> <53C7D666.6000405@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <53C7D666.6000405@amd.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 17, 2014 at 04:57:58PM +0300, Oded Gabbay wrote: > Forgot to add mm mailing list. Sorry. > > This patch enables the amdkfd driver to retrieve the kfd_process > object from the process's mm_struct. This is needed because kfd_process > lifespan is bound to the process's mm_struct lifespan. > > When amdkfd is notified about an mm_struct tear-down, it checks if the > kfd_process pointer is valid. If so, it releases the kfd_process object > and all relevant resources. > > In v3 of the patchset I will update the binding to match the final discussions > on [PATCH 1/8] mmput: use notifier chain to call subsystem exit handler. > In the meantime, I'm going to try and see if I can drop the kfd_process > in mm_struct and remove the use of the new notification chain in mmput. > Instead, I will try to use the mmu release notifier. So the mmput notifier chain will not happen. I did a patch with call_srcu and adding couple more helper to mmu_notifier. I will send that today for review. That being said, adding a device driver specific to mm_struct will most likely be a big no. I am myself gonna remove hmm from mm_struct as people are reluctant to see such change. Cheers, J?r?me > > Signed-off-by: Oded Gabbay > --- > include/linux/mm_types.h | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h > index 678097c..ff71496 100644 > --- a/include/linux/mm_types.h > +++ b/include/linux/mm_types.h > @@ -20,6 +20,10 @@ > struct hmm; > #endif > +#if defined(CONFIG_HSA_RADEON) || defined(CONFIG_HSA_RADEON_MODULE) > +struct kfd_process; > +#endif > + > #ifndef AT_VECTOR_SIZE_ARCH > #define AT_VECTOR_SIZE_ARCH 0 > #endif > @@ -439,6 +443,16 @@ struct mm_struct { > */ > struct hmm *hmm; > #endif > +#if defined(CONFIG_HSA_RADEON) || defined(CONFIG_HSA_RADEON_MODULE) > + /* > + * kfd always register an mmu_notifier we rely on mmu notifier to keep > + * refcount on mm struct as well as forbiding registering kfd on a > + * dying mm > + * > + * This field is set with mmap_sem old in write mode. > + */ > + struct kfd_process *kfd_process; > +#endif > #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS > pgtable_t pmd_huge_pte; /* protected by page_table_lock */ > #endif > -- > 1.9.1 > -- 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/