[Intel-gfx] [PATCH 14/20] drm/i915/selftests: exercise mmap migration

Matthew Auld
2022-01-26T15:22:56Z

Exercise each of the migration scenarios, verifying that the final
placement and buffer contents match our expectations.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
---
.../drm/i915/gem/selftests/i915_gem_mman.c | 306 ++++++++++++++++++
1 file changed, 306 insertions(+)

diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
index ba29767348be..d2c1071df98a 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
@@ -10,6 +10,7 @@
#include "gt/intel_gpu_commands.h"
#include "gt/intel_gt.h"
#include "gt/intel_gt_pm.h"
+#include "gt/intel_migrate.h"
#include "gem/i915_gem_region.h"
#include "huge_gem_object.h"
#include "i915_selftest.h"
@@ -999,6 +1000,310 @@ static int igt_mmap(void *arg)
return 0;
}

+static void igt_close_objects(struct drm_i915_private *i915,
+ struct list_head *objects)
+{
+ struct drm_i915_gem_object *obj, *on;
+
+ list_for_each_entry_safe(obj, on, objects, st_link) {
+ i915_gem_object_lock(obj, NULL);
+ if (i915_gem_object_has_pinned_pages(obj))
+ i915_gem_object_unpin_pages(obj);
+ /* No polluting the memory region between tests */
+ __i915_gem_object_put_pages(obj);
+ i915_gem_object_unlock(obj);
+ list_del(&obj->st_link);
+ i915_gem_object_put(obj);
+ }
+
+ cond_resched();
+
+ i915_gem_drain_freed_objects(i915);
+}
+
+static void igt_make_evictable(struct list_head *objects)
+{
+ struct drm_i915_gem_object *obj;
+
+ list_for_each_entry(obj, objects, st_link) {
+ i915_gem_object_lock(obj, NULL);
+ if (i915_gem_object_has_pinned_pages(obj))
+ i915_gem_object_unpin_pages(obj);
+ i915_gem_object_unlock(obj);
+ }
+
+ cond_resched();
+}
+
+static int igt_fill_mappable(struct intel_memory_region *mr,
+ struct list_head *objects)
+{
+ u64 size, total;
+ int err;
+
+ total = 0;
+ size = mr->io_size;
+ do {
+ struct drm_i915_gem_object *obj;
+
+ obj = i915_gem_object_create_region(mr, size, 0, 0);
+ if (IS_ERR(obj)) {
+ err = PTR_ERR(obj);
+ goto err_close;
+ }
+
+ list_add(&obj->st_link, objects);
+
+ err = i915_gem_object_pin_pages_unlocked(obj);
+ if (err) {
+ if (err != -ENXIO && err != -ENOMEM)
+ goto err_close;
+
+ if (size == mr->min_page_size) {
+ err = 0;
+ break;
+ }
+
+ size >>= 1;
+ continue;
+ }
+
+ total += obj->base.size;
+ } while (1);
+
+ pr_info("%s filled=%lluMiB\n", __func__, total >> 20);
+ return 0;
+
+err_close:
+ igt_close_objects(mr->i915, objects);
+ return err;
+}
+
+static int ___igt_mmap_migrate(struct drm_i915_private *i915,
+ struct drm_i915_gem_object *obj,
+ unsigned long addr,
+ bool unfaultable)
+{
+ struct vm_area_struct *area;
+ int err = 0, i;
+
+ pr_info("igt_mmap(%s, %d) @ %lx\n",
+ obj->mm.region->name, I915_MMAP_TYPE_FIXED, addr);
+
+ mmap_read_lock(current->mm);
+ area = vma_lookup(current->mm, addr);
+ mmap_read_unlock(current->mm);
+ if (!area) {
+ pr_err("%s: Did not create a vm_area_struct for the mmap\n",
+ obj->mm.region->name);
+ err = -EINVAL;
+ goto out_unmap;
+ }
+
+ for (i = 0; i < obj->base.size / sizeof(u32); i++) {
+ u32 __user *ux = u64_to_user_ptr((u64)(addr + i * sizeof(*ux)));
+ u32 x;
+
+ if (get_user(x, ux)) {
+ err = -EFAULT;
+ if (!unfaultable) {
+ pr_err("%s: Unable to read from mmap, offset:%zd\n",
+ obj->mm.region->name, i * sizeof(x));
+ goto out_unmap;
+ }
+
+ continue;
+ }
+
+ if (unfaultable) {
+ pr_err("%s: Faulted unmappable memory\n",
+ obj->mm.region->name);
+ err = -EINVAL;
+ goto out_unmap;
+ }
+
+ if (x != expand32(POISON_INUSE)) {
+ pr_err("%s: Read incorrect value from mmap, offset:%zd, found:%x, expected:%x\n",
+ obj->mm.region->name,
+ i * sizeof(x), x, expand32(POISON_INUSE));
+ err = -EINVAL;
+ goto out_unmap;
+ }
+
+ x = expand32(POISON_FREE);
+ if (put_user(x, ux)) {
+ pr_err("%s: Unable to write to mmap, offset:%zd\n",
+ obj->mm.region->name, i * sizeof(x));
+ err = -EFAULT;
+ goto out_unmap;
+ }
+ }
+
+ if (unfaultable) {
+ if (err == -EFAULT)
+ err = 0;
+ } else {
+ obj->flags &= ~I915_BO_ALLOC_TOPDOWN;
+ err = wc_check(obj);
+ }
+out_unmap:
+ vm_munmap(addr, obj->base.size);
+ return err;
+}
+
+#define IGT_MMAP_MIGRATE_TOPDOWN (1<<0)
+#define IGT_MMAP_MIGRATE_FILL (1<<1)
+#define IGT_MMAP_MIGRATE_EVICTABLE (1<<2)
+#define IGT_MMAP_MIGRATE_UNFAULTABLE (1<<3)
+static int __igt_mmap_migrate(struct intel_memory_region **placements,
+ int n_placements,
+ struct intel_memory_region *expected_mr,
+ unsigned int flags)
+{
+ struct drm_i915_private *i915 = placements[0]->i915;
+ struct drm_i915_gem_object *obj;
+ struct i915_gem_ww_ctx ww;
+ struct i915_request *rq = NULL;
+ unsigned long addr;
+ LIST_HEAD(objects);
+ u64 offset;
+ int err;
+
+ obj = __i915_gem_object_create_user(i915, PAGE_SIZE,
+ placements,
+ n_placements);
+ if (IS_ERR(obj))
+ return PTR_ERR(obj);
+
+ if (flags & IGT_MMAP_MIGRATE_TOPDOWN)
+ obj->flags |= I915_BO_ALLOC_TOPDOWN;
+
+ err = __assign_mmap_offset(obj, I915_MMAP_TYPE_FIXED, &offset, NULL);
+ if (err)
+ goto out_put;
+
+ /*
+ * This will eventually create a GEM context, due to opening dummy drm
+ * file, which needs a tiny amount of mappable device memory for the top
+ * level paging structures(and perhaps scratch), so make sure we
+ * allocate early, to avoid tears.
+ */
+ addr = igt_mmap_offset(i915, offset, obj->base.size,
+ PROT_WRITE, MAP_SHARED);
+ if (IS_ERR_VALUE(addr)) {
+ err = addr;
+ goto out_put;
+ }
+
+ if (flags & IGT_MMAP_MIGRATE_FILL) {
+ err = igt_fill_mappable(placements[0], &objects);
+ if (err)
+ goto out_put;
+ }
+
+ for_i915_gem_ww(&ww, err, true) {
+ err = i915_gem_object_lock(obj, &ww);
+ if (err)
+ continue;
+
+ err = i915_gem_object_pin_pages(obj);
+ if (err)
+ continue;
+
+ err = intel_context_migrate_clear(to_gt(i915)->migrate.context, NULL,
+ obj->mm.pages->sgl, obj->cache_level,
+ i915_gem_object_is_lmem(obj),
+ expand32(POISON_INUSE), &rq);
+ i915_gem_object_unpin_pages(obj);
+ if (rq) {
+ dma_resv_add_excl_fence(obj->base.resv, &rq->fence);
+ i915_gem_object_set_moving_fence(obj, &rq->fence);
+ i915_request_put(rq);
+ }
+ if (err)
+ continue;
+ }
+ if (err)
+ goto out_put;
+
+ if (flags & IGT_MMAP_MIGRATE_EVICTABLE)
+ igt_make_evictable(&objects);
+
+ err = ___igt_mmap_migrate(i915, obj, addr,
+ flags & IGT_MMAP_MIGRATE_UNFAULTABLE);
+ if (!err && obj->mm.region != expected_mr) {
+ pr_err("%s region mismatch %s\n", __func__, expected_mr->name);
+ err = -EINVAL;
+ }
+
+out_put:
+ i915_gem_object_put(obj);
+ igt_close_objects(i915, &objects);
+ return err;
+}
+
+static int igt_mmap_migrate(void *arg)
+{
+ struct drm_i915_private *i915 = arg;
+ struct intel_memory_region *system = i915->mm.regions[INTEL_REGION_SMEM];
+ struct intel_memory_region *mr;
+ enum intel_region_id id;
+
+ for_each_memory_region(mr, i915, id) {
+ struct intel_memory_region *mixed[] = { mr, system };
+ struct intel_memory_region *single[] = { mr };
+ int err;
+
+ if (mr->private)
+ continue;
+
+ if (!mr->io_size || mr->io_size == mr->total)
+ continue;
+
+ /*
+ * Allocate in the mappable portion, should be no suprises here.
+ */
+ err = __igt_mmap_migrate(mixed, ARRAY_SIZE(mixed), mr, 0);
+ if (err)
+ return err;
+
+ /*
+ * Allocate in the non-mappable portion, but force migrating to
+ * the mappable portion on fault (LMEM -> LMEM)
+ */
+ err = __igt_mmap_migrate(single, ARRAY_SIZE(single), mr,
+ IGT_MMAP_MIGRATE_TOPDOWN |
+ IGT_MMAP_MIGRATE_FILL |
+ IGT_MMAP_MIGRATE_EVICTABLE);
+ if (err)
+ return err;
+
+ /*
+ * Allocate in the non-mappable portion, but force spilling into
+ * system memory on fault (LMEM -> SMEM)
+ */
+ err = __igt_mmap_migrate(mixed, ARRAY_SIZE(mixed), system,
+ IGT_MMAP_MIGRATE_TOPDOWN |
+ IGT_MMAP_MIGRATE_FILL);
+ if (err)
+ return err;
+
+ /*
+ * Allocate in the non-mappable portion, but since the mappable
+ * portion is already full, and we can't spill to system memory,
+ * then we should expect the fault to fail.
+ */
+ err = __igt_mmap_migrate(single, ARRAY_SIZE(single), mr,
+ IGT_MMAP_MIGRATE_TOPDOWN |
+ IGT_MMAP_MIGRATE_FILL |
+ IGT_MMAP_MIGRATE_UNFAULTABLE);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
static const char *repr_mmap_type(enum i915_mmap_type type)
{
switch (type) {
@@ -1424,6 +1729,7 @@ int i915_gem_mman_live_selftests(struct drm_i915_private *i915)
SUBTEST(igt_smoke_tiling),
SUBTEST(igt_mmap_offset_exhaustion),
SUBTEST(igt_mmap),
+ SUBTEST(igt_mmap_migrate),
SUBTEST(igt_mmap_access),
SUBTEST(igt_mmap_revoke),
SUBTEST(igt_mmap_gpu),
--
2.34.1