From: Ralph Campbell <rcampbell@nvidia.com>
To: <linux-rdma@vger.kernel.org>, <linux-mm@kvack.org>,
<nouveau@lists.freedesktop.org>, <kvm-ppc@vger.kernel.org>,
<linux-kselftest@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Cc: Jerome Glisse <jglisse@redhat.com>,
John Hubbard <jhubbard@nvidia.com>,
Christoph Hellwig <hch@lst.de>,
Jason Gunthorpe <jgg@mellanox.com>,
"Andrew Morton" <akpm@linux-foundation.org>,
Shuah Khan <shuah@kernel.org>, "Ben Skeggs" <bskeggs@redhat.com>,
Bharata B Rao <bharata@linux.ibm.com>,
"Ralph Campbell" <rcampbell@nvidia.com>
Subject: [PATCH v3 5/5] mm/hmm/test: use the new migration invalidation
Date: Tue, 21 Jul 2020 14:31:19 -0700 [thread overview]
Message-ID: <20200721213119.32344-6-rcampbell@nvidia.com> (raw)
In-Reply-To: <20200721213119.32344-1-rcampbell@nvidia.com>
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 <rcampbell@nvidia.com>
---
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);
--
2.20.1
prev parent reply other threads:[~2020-07-21 21:31 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-21 21:31 [PATCH v3 0/5] mm/migrate: avoid device private invalidations Ralph Campbell
2020-07-21 21:31 ` [PATCH v3 1/5] nouveau: fix storing invalid ptes Ralph Campbell
2020-07-21 21:31 ` [PATCH v3 2/5] mm/migrate: add a flags parameter to migrate_vma Ralph Campbell
2020-07-22 11:51 ` Bharata B Rao
2020-07-21 21:31 ` [PATCH v3 3/5] mm/notifier: add migration invalidation type Ralph Campbell
2020-07-21 21:31 ` [PATCH v3 4/5] nouveau/svm: use the new migration invalidation Ralph Campbell
2020-07-21 21:31 ` Ralph Campbell [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200721213119.32344-6-rcampbell@nvidia.com \
--to=rcampbell@nvidia.com \
--cc=akpm@linux-foundation.org \
--cc=bharata@linux.ibm.com \
--cc=bskeggs@redhat.com \
--cc=hch@lst.de \
--cc=jgg@mellanox.com \
--cc=jglisse@redhat.com \
--cc=jhubbard@nvidia.com \
--cc=kvm-ppc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-rdma@vger.kernel.org \
--cc=nouveau@lists.freedesktop.org \
--cc=shuah@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).