From patchwork Tue Jul 21 21:31:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ralph Campbell X-Patchwork-Id: 11676803 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B3E7B159A for ; Tue, 21 Jul 2020 21:31:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99A7B20729 for ; Tue, 21 Jul 2020 21:31:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="pfje3ZGP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731316AbgGUVbm (ORCPT ); Tue, 21 Jul 2020 17:31:42 -0400 Received: from hqnvemgate26.nvidia.com ([216.228.121.65]:12490 "EHLO hqnvemgate26.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731293AbgGUVbg (ORCPT ); Tue, 21 Jul 2020 17:31:36 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate26.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Tue, 21 Jul 2020 14:31:22 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Tue, 21 Jul 2020 14:31:35 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 21 Jul 2020 14:31:35 -0700 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 21 Jul 2020 21:31:25 +0000 Received: from hqnvemgw03.nvidia.com (10.124.88.68) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Tue, 21 Jul 2020 21:31:26 +0000 Received: from rcampbell-dev.nvidia.com (Not Verified[10.110.48.66]) by hqnvemgw03.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Tue, 21 Jul 2020 14:31:26 -0700 From: Ralph Campbell To: , , , , , CC: Jerome Glisse , John Hubbard , Christoph Hellwig , Jason Gunthorpe , "Andrew Morton" , Shuah Khan , "Ben Skeggs" , Bharata B Rao , "Ralph Campbell" Subject: [PATCH v3 5/5] mm/hmm/test: use the new migration invalidation Date: Tue, 21 Jul 2020 14:31:19 -0700 Message-ID: <20200721213119.32344-6-rcampbell@nvidia.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200721213119.32344-1-rcampbell@nvidia.com> References: <20200721213119.32344-1-rcampbell@nvidia.com> MIME-Version: 1.0 X-NVConfidentiality: public DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1595367082; bh=dV0F2IGIbSa3UBr9FPynu9ekSSnn2qKSM3AxyUbNMFQ=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:X-NVConfidentiality: Content-Transfer-Encoding:Content-Type; b=pfje3ZGPKvbmEuIpiYR54C1oU2sba42jUTPeyo9lQu3WTQThk65+loh+eB+wSoEIh N07/umNUYu7CbxQyOsKkfIkuQhuTXVARUPAXP+AmWW92zLGD8Yj3rc+yr2w6p3swkV CWx4hst7sJBQwRB81WTcTZmo23MopnU8P+1kXcLN/yuD9FSrdZXgY806Mk3Z330tqb YAUeJBuMz9nBMYsSk4hzsmTcWI+tJVwHt5mz/8+8z/c+oDor9rN4dcDuBZhdLA/F8+ wvOTagUh7sDm0G12wWTYCR1I9bHTmBGmrp+S/GtDZua+EN3PWrsUg3kQZVGsanCUNd +iuPWhcB5EhCw== Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Use the new MMU_NOTIFY_MIGRATE event to skip MMU invalidations of device private memory and handle the invalidation in the driver as part of migrating device private memory. Signed-off-by: Ralph Campbell --- lib/test_hmm.c | 30 +++++++++++++++----------- tools/testing/selftests/vm/hmm-tests.c | 18 ++++++++++++---- 2 files changed, 31 insertions(+), 17 deletions(-) diff --git a/lib/test_hmm.c b/lib/test_hmm.c index 74c6ee66ef15..9abc9ad3140f 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -214,6 +214,14 @@ static bool dmirror_interval_invalidate(struct mmu_interval_notifier *mni, { struct dmirror *dmirror = container_of(mni, struct dmirror, notifier); + /* + * Ignore invalidation callbacks for device private pages since + * the invalidation is handled as part of the migration process. + */ + if (range->event == MMU_NOTIFY_MIGRATE && + range->migrate_pgmap_owner == dmirror->mdevice) + return true; + if (mmu_notifier_range_blockable(range)) mutex_lock(&dmirror->mutex); else if (!mutex_trylock(&dmirror->mutex)) @@ -702,7 +710,7 @@ static int dmirror_migrate(struct dmirror *dmirror, args.dst = dst_pfns; args.start = addr; args.end = next; - args.pgmap_owner = NULL; + args.pgmap_owner = dmirror->mdevice; args.flags = MIGRATE_VMA_SELECT_SYSTEM; ret = migrate_vma_setup(&args); if (ret) @@ -992,7 +1000,7 @@ static void dmirror_devmem_free(struct page *page) } static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, - struct dmirror_device *mdevice) + struct dmirror *dmirror) { const unsigned long *src = args->src; unsigned long *dst = args->dst; @@ -1014,6 +1022,7 @@ static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, continue; lock_page(dpage); + xa_erase(&dmirror->pt, addr >> PAGE_SHIFT); copy_highpage(dpage, spage); *dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; if (*src & MIGRATE_PFN_WRITE) @@ -1022,15 +1031,6 @@ static vm_fault_t dmirror_devmem_fault_alloc_and_copy(struct migrate_vma *args, return 0; } -static void dmirror_devmem_fault_finalize_and_map(struct migrate_vma *args, - struct dmirror *dmirror) -{ - /* Invalidate the device's page table mapping. */ - mutex_lock(&dmirror->mutex); - dmirror_do_update(dmirror, args->start, args->end); - mutex_unlock(&dmirror->mutex); -} - static vm_fault_t dmirror_devmem_fault(struct vm_fault *vmf) { struct migrate_vma args; @@ -1060,11 +1060,15 @@ static vm_fault_t dmirror_devmem_fault(struct vm_fault *vmf) if (migrate_vma_setup(&args)) return VM_FAULT_SIGBUS; - ret = dmirror_devmem_fault_alloc_and_copy(&args, dmirror->mdevice); + ret = dmirror_devmem_fault_alloc_and_copy(&args, dmirror); if (ret) return ret; migrate_vma_pages(&args); - dmirror_devmem_fault_finalize_and_map(&args, dmirror); + /* + * No device finalize step is needed since + * dmirror_devmem_fault_alloc_and_copy() will have already + * invalidated the device page table. + */ migrate_vma_finalize(&args); return 0; } diff --git a/tools/testing/selftests/vm/hmm-tests.c b/tools/testing/selftests/vm/hmm-tests.c index b533dd08da1d..91d38a29956b 100644 --- a/tools/testing/selftests/vm/hmm-tests.c +++ b/tools/testing/selftests/vm/hmm-tests.c @@ -881,8 +881,9 @@ TEST_F(hmm, migrate) } /* - * Migrate anonymous memory to device private memory and fault it back to system - * memory. + * Migrate anonymous memory to device private memory and fault some of it back + * to system memory, then try migrating the resulting mix of system and device + * private memory to the device. */ TEST_F(hmm, migrate_fault) { @@ -924,8 +925,17 @@ TEST_F(hmm, migrate_fault) for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i) ASSERT_EQ(ptr[i], i); - /* Fault pages back to system memory and check them. */ - for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i) + /* Fault half the pages back to system memory and check them. */ + for (i = 0, ptr = buffer->ptr; i < size / (2 * sizeof(*ptr)); ++i) + ASSERT_EQ(ptr[i], i); + + /* Migrate memory to the device again. */ + ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_MIGRATE, buffer, npages); + ASSERT_EQ(ret, 0); + ASSERT_EQ(buffer->cpages, npages); + + /* Check what the device read. */ + for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i) ASSERT_EQ(ptr[i], i); hmm_buffer_free(buffer);