Re: [PATCH v5 09/10] tools: update hmm-test to support device coherent type

Hi Alistair, This is the last patch to be reviewed from this series. It already has the changes from your last feedback (V3). Would you mind to take a look? Thanks a lot for reviewing the rest!

Regards, Alex Sierra

On 1/28/2022 2:08 PM, Alex Sierra wrote:

Test cases such as migrate_fault and migrate_multiple, were modified to explicit migrate from device to sys memory without the need of page faults, when using device coherent type.

Snapshot test case updated to read memory device type first and based on that, get the proper returned results migrate_ping_pong test case added to test explicit migration from device to sys memory for both private and coherent zone types.

Helpers to migrate from device to sys memory and vicerversa were also added.

Signed-off-by: Alex Sierra alex.sierra@amd.com Acked-by: Felix Kuehling Felix.Kuehling@amd.com

---

v2: Set FIXTURE_VARIANT to add multiple device types to the FIXTURE. This will run all the tests for each device type (private and coherent) in case both existed during hmm-test driver probed. v4: Check for the number of pages successfully migrated from coherent device to system at migrate_multiple test.

---

tools/testing/selftests/vm/hmm-tests.c | 123 ++++++++++++++++++++----- 1 file changed, 102 insertions(+), 21 deletions(-)

diff --git a/tools/testing/selftests/vm/hmm-tests.c b/tools/testing/selftests/vm/hmm-tests.c index 203323967b50..84ec8c4a1dc7 100644 --- a/tools/testing/selftests/vm/hmm-tests.c +++ b/tools/testing/selftests/vm/hmm-tests.c @@ -44,6 +44,14 @@ struct hmm_buffer { int fd; uint64_t cpages; uint64_t faults;

• int zone_device_type;

+};

+enum {

• HMM_PRIVATE_DEVICE_ONE,

• HMM_PRIVATE_DEVICE_TWO,

• HMM_COHERENCE_DEVICE_ONE,

• HMM_COHERENCE_DEVICE_TWO, };

  #define TWOMEG (1 << 21)

@@ -60,6 +68,21 @@ FIXTURE(hmm) unsigned int page_shift; };

+FIXTURE_VARIANT(hmm) +{

• int device_number;

+};

+FIXTURE_VARIANT_ADD(hmm, hmm_device_private) +{

• .device_number = HMM_PRIVATE_DEVICE_ONE,

+};

+FIXTURE_VARIANT_ADD(hmm, hmm_device_coherent) +{

• .device_number = HMM_COHERENCE_DEVICE_ONE,

+};

• FIXTURE(hmm2) { int fd0;

@@ -68,6 +91,24 @@ FIXTURE(hmm2) unsigned int page_shift; };

+FIXTURE_VARIANT(hmm2) +{

• int device_number0;
• int device_number1;

+};

+FIXTURE_VARIANT_ADD(hmm2, hmm2_device_private) +{

• .device_number0 = HMM_PRIVATE_DEVICE_ONE,
• .device_number1 = HMM_PRIVATE_DEVICE_TWO,

+};

+FIXTURE_VARIANT_ADD(hmm2, hmm2_device_coherent) +{

• .device_number0 = HMM_COHERENCE_DEVICE_ONE,
• .device_number1 = HMM_COHERENCE_DEVICE_TWO,

+};

• static int hmm_open(int unit) { char pathname[HMM_PATH_MAX];

@@ -81,12 +122,19 @@ static int hmm_open(int unit) return fd; }

+static bool hmm_is_coherent_type(int dev_num) +{

• return (dev_num >= HMM_COHERENCE_DEVICE_ONE);

+}

• FIXTURE_SETUP(hmm) { self->page_size = sysconf(_SC_PAGE_SIZE); self->page_shift = ffs(self->page_size) - 1;

• self->fd = hmm_open(0);

• self->fd = hmm_open(variant->device_number);
• if (self->fd < 0 && hmm_is_coherent_type(variant->device_number))

• SKIP(exit(0), "DEVICE_COHERENT not available");
  

  ASSERT_GE(self->fd, 0); }

@@ -95,9 +143,11 @@ FIXTURE_SETUP(hmm2) self->page_size = sysconf(_SC_PAGE_SIZE); self->page_shift = ffs(self->page_size) - 1;

• self->fd0 = hmm_open(0);

• self->fd0 = hmm_open(variant->device_number0);
• if (self->fd0 < 0 && hmm_is_coherent_type(variant->device_number0))

• SKIP(exit(0), "DEVICE_COHERENT not available");
  

  ASSERT_GE(self->fd0, 0);

• self->fd1 = hmm_open(1);

• self->fd1 = hmm_open(variant->device_number1); ASSERT_GE(self->fd1, 0); }

@@ -144,6 +194,7 @@ static int hmm_dmirror_cmd(int fd, } buffer->cpages = cmd.cpages; buffer->faults = cmd.faults;

• buffer->zone_device_type = cmd.zone_device_type;

  return 0; }

@@ -211,6 +262,20 @@ static void hmm_nanosleep(unsigned int n) nanosleep(&t, NULL); }

+static int hmm_migrate_sys_to_dev(int fd,

• 		   struct hmm_buffer *buffer,
  

• 		   unsigned long npages)
  

+{

• return hmm_dmirror_cmd(fd, HMM_DMIRROR_MIGRATE_TO_DEV, buffer, npages);

+}

+static int hmm_migrate_dev_to_sys(int fd,

• 		   struct hmm_buffer *buffer,
  

• 		   unsigned long npages)
  

+{

• return hmm_dmirror_cmd(fd, HMM_DMIRROR_MIGRATE_TO_SYS, buffer, npages);

+}

• /*
  • Simple NULL test of device open/close.
  */

@@ -875,7 +940,7 @@ TEST_F(hmm, migrate) ptr[i] = i;

/* Migrate memory to device. */

• ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_MIGRATE, buffer, npages);

• ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages); ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, npages);

@@ -923,7 +988,7 @@ TEST_F(hmm, migrate_fault) ptr[i] = i;

/* Migrate memory to device. */

• ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_MIGRATE, buffer, npages);

• ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages); ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, npages);

@@ -936,7 +1001,7 @@ TEST_F(hmm, migrate_fault) ASSERT_EQ(ptr[i], i);

/* Migrate memory to the device again. */

• ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_MIGRATE, buffer, npages);

• ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages); ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, npages);

@@ -976,7 +1041,7 @@ TEST_F(hmm, migrate_shared) ASSERT_NE(buffer->ptr, MAP_FAILED);

/* Migrate memory to device. */

• ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_MIGRATE, buffer, npages);

• ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages); ASSERT_EQ(ret, -ENOENT);

  hmm_buffer_free(buffer);

@@ -1015,7 +1080,7 @@ TEST_F(hmm2, migrate_mixed) p = buffer->ptr;

/* Migrating a protected area should be an error. */

• ret = hmm_dmirror_cmd(self->fd1, HMM_DMIRROR_MIGRATE, buffer, npages);

• ret = hmm_migrate_sys_to_dev(self->fd1, buffer, npages); ASSERT_EQ(ret, -EINVAL);

  /* Punch a hole after the first page address. */

@@ -1023,7 +1088,7 @@ TEST_F(hmm2, migrate_mixed) ASSERT_EQ(ret, 0);

/* We expect an error if the vma doesn't cover the range. */

• ret = hmm_dmirror_cmd(self->fd1, HMM_DMIRROR_MIGRATE, buffer, 3);

• ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 3); ASSERT_EQ(ret, -EINVAL);

  /* Page 2 will be a read-only zero page. */

@@ -1055,13 +1120,13 @@ TEST_F(hmm2, migrate_mixed)

/* Now try to migrate pages 2-5 to device 1. */ buffer->ptr = p + 2 * self->page_size;

• ret = hmm_dmirror_cmd(self->fd1, HMM_DMIRROR_MIGRATE, buffer, 4);

• ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 4); ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, 4);

  /* Page 5 won't be migrated to device 0 because it's on device 1. */ buffer->ptr = p + 5 * self->page_size;

• ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_MIGRATE, buffer, 1);

• ret = hmm_migrate_sys_to_dev(self->fd0, buffer, 1); ASSERT_EQ(ret, -ENOENT); buffer->ptr = p;

@@ -1070,8 +1135,12 @@ TEST_F(hmm2, migrate_mixed) }

/*

• • Migrate anonymous memory to device private memory and fault it back to system
• • memory multiple times.

• • Migrate anonymous memory to device memory and back to system memory
• • multiple times. In case of private zone configuration, this is done
• • through fault pages accessed by CPU. In case of coherent zone configuration,
• • the pages from the device should be explicitly migrated back to system memory.
• • The reason is Coherent device zone has coherent access by CPU, therefore
• • it will not generate any page fault.
  */ TEST_F(hmm, migrate_multiple) {

@@ -1107,8 +1176,7 @@ TEST_F(hmm, migrate_multiple) ptr[i] = i;

/* Migrate memory to device. */

• ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_MIGRATE, buffer,
  

• 		      npages);
  

• ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
  

  ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, npages);

@@ -1116,7 +1184,13 @@ TEST_F(hmm, migrate_multiple) 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. */
  

• /* Migrate back to system memory and check them. */
  

• if (hmm_is_coherent_type(variant->device_number)) {
  

• 	ret = hmm_migrate_dev_to_sys(self->fd, buffer, npages);
  

• 	ASSERT_EQ(ret, 0);
  

• 	ASSERT_EQ(buffer->cpages, npages);
  

• }
  

• for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i) ASSERT_EQ(ptr[i], i);

@@ -1354,13 +1428,13 @@ TEST_F(hmm2, snapshot)

/* Page 5 will be migrated to device 0. */ buffer->ptr = p + 5 * self->page_size;

• ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_MIGRATE, buffer, 1);

• ret = hmm_migrate_sys_to_dev(self->fd0, buffer, 1); ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, 1);

  /* Page 6 will be migrated to device 1. */ buffer->ptr = p + 6 * self->page_size;

• ret = hmm_dmirror_cmd(self->fd1, HMM_DMIRROR_MIGRATE, buffer, 1);

• ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 1); ASSERT_EQ(ret, 0); ASSERT_EQ(buffer->cpages, 1);

@@ -1377,9 +1451,16 @@ TEST_F(hmm2, snapshot) ASSERT_EQ(m[2], HMM_DMIRROR_PROT_ZERO | HMM_DMIRROR_PROT_READ); ASSERT_EQ(m[3], HMM_DMIRROR_PROT_READ); ASSERT_EQ(m[4], HMM_DMIRROR_PROT_WRITE);

• ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL |

• 	HMM_DMIRROR_PROT_WRITE);
  

• ASSERT_EQ(m[6], HMM_DMIRROR_PROT_NONE);

• if (!hmm_is_coherent_type(variant->device_number0)) {

• ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL |
  

• 		HMM_DMIRROR_PROT_WRITE);
  

• ASSERT_EQ(m[6], HMM_DMIRROR_PROT_NONE);
  

• } else {

• ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL |
  

• 		HMM_DMIRROR_PROT_WRITE);
  

• ASSERT_EQ(m[6], HMM_DMIRROR_PROT_DEV_COHERENT_REMOTE |
  

• 		HMM_DMIRROR_PROT_WRITE);
  

• }

  hmm_buffer_free(buffer); }