[Intel-gfx] [PATCH 18/61] drm/i915: Make ring submission compatible with obj->mm.lock removal.

Maarten Lankhorst
2020-10-02T13:00:08Z

We map the initial context during first pin.

This allows us to remove pin_map from state allocation, which saves
us a few retry loops. We won't need this until first pin anyway.

intel_ring_submission_setup() is also reworked slightly to do all
pinning in a single ww loop.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
.../gpu/drm/i915/gt/intel_ring_submission.c | 177 +++++++++++-------
1 file changed, 111 insertions(+), 66 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index a41b43f445b8..10904a84aeb7 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -478,6 +478,26 @@ static void ring_context_destroy(struct kref *ref)
intel_context_free(ce);
}

+static int ring_context_init_default_state(struct intel_context *ce,
+ struct i915_gem_ww_ctx *ww)
+{
+ struct drm_i915_gem_object *obj = ce->state->obj;
+ void *vaddr;
+
+ vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB);
+ if (IS_ERR(vaddr))
+ return PTR_ERR(vaddr);
+
+ shmem_read(ce->engine->default_state, 0,
+ vaddr, ce->engine->context_size);
+
+ i915_gem_object_flush_map(obj);
+ __i915_gem_object_release_map(obj);
+
+ __set_bit(CONTEXT_VALID_BIT, &ce->flags);
+ return 0;
+}
+
static int ring_context_pre_pin(struct intel_context *ce,
struct i915_gem_ww_ctx *ww,
void **unused)
@@ -485,6 +505,13 @@ static int ring_context_pre_pin(struct intel_context *ce,
struct i915_address_space *vm;
int err = 0;

+ if (ce->engine->default_state &&
+ !test_bit(CONTEXT_VALID_BIT, &ce->flags)) {
+ err = ring_context_init_default_state(ce, ww);
+ if (err)
+ return err;
+ }
+
vm = vm_alias(ce->vm);
if (vm)
err = gen6_ppgtt_pin(i915_vm_to_ppgtt((vm)), ww);
@@ -540,22 +567,6 @@ alloc_context_vma(struct intel_engine_cs *engine)
if (IS_IVYBRIDGE(i915))
i915_gem_object_set_cache_coherency(obj, I915_CACHE_L3_LLC);

- if (engine->default_state) {
- void *vaddr;
-
- vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB);
- if (IS_ERR(vaddr)) {
- err = PTR_ERR(vaddr);
- goto err_obj;
- }
-
- shmem_read(engine->default_state, 0,
- vaddr, engine->context_size);
-
- i915_gem_object_flush_map(obj);
- __i915_gem_object_release_map(obj);
- }
-
vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
if (IS_ERR(vma)) {
err = PTR_ERR(vma);
@@ -587,8 +598,6 @@ static int ring_context_alloc(struct intel_context *ce)
return PTR_ERR(vma);

ce->state = vma;
- if (engine->default_state)
- __set_bit(CONTEXT_VALID_BIT, &ce->flags);
}

return 0;
@@ -1184,37 +1193,15 @@ static int gen7_ctx_switch_bb_setup(struct intel_engine_cs * const engine,
return gen7_setup_clear_gpr_bb(engine, vma);
}

-static int gen7_ctx_switch_bb_init(struct intel_engine_cs *engine)
+static int gen7_ctx_switch_bb_init(struct intel_engine_cs *engine,
+ struct i915_gem_ww_ctx *ww,
+ struct i915_vma *vma)
{
- struct drm_i915_gem_object *obj;
- struct i915_vma *vma;
- int size;
int err;

- size = gen7_ctx_switch_bb_setup(engine, NULL /* probe size */);
- if (size <= 0)
- return size;
-
- size = ALIGN(size, PAGE_SIZE);
- obj = i915_gem_object_create_internal(engine->i915, size);
- if (IS_ERR(obj))
- return PTR_ERR(obj);
-
- vma = i915_vma_instance(obj, engine->gt->vm, NULL);
- if (IS_ERR(vma)) {
- err = PTR_ERR(vma);
- goto err_obj;
- }
-
- vma->private = intel_context_create(engine); /* dummy residuals */
- if (IS_ERR(vma->private)) {
- err = PTR_ERR(vma->private);
- goto err_obj;
- }
-
- err = i915_vma_pin(vma, 0, 0, PIN_USER | PIN_HIGH);
+ err = i915_vma_pin_ww(vma, ww, 0, 0, PIN_USER | PIN_HIGH);
if (err)
- goto err_private;
+ return err;

err = i915_vma_sync(vma);
if (err)
@@ -1229,17 +1216,50 @@ static int gen7_ctx_switch_bb_init(struct intel_engine_cs *engine)

err_unpin:
i915_vma_unpin(vma);
-err_private:
- intel_context_put(vma->private);
-err_obj:
- i915_gem_object_put(obj);
return err;
}

+static struct i915_vma *gen7_ctx_vma(struct intel_engine_cs *engine)
+{
+ struct drm_i915_gem_object *obj;
+ struct i915_vma *vma;
+ int size, err;
+
+ if (!IS_HASWELL(engine->i915) || engine->class != RENDER_CLASS)
+ return 0;
+
+ err = gen7_ctx_switch_bb_setup(engine, NULL /* probe size */);
+ if (err <= 0)
+ return ERR_PTR(err);
+
+ size = ALIGN(err, PAGE_SIZE);
+
+ obj = i915_gem_object_create_internal(engine->i915, size);
+ if (IS_ERR(obj))
+ return ERR_CAST(obj);
+
+ vma = i915_vma_instance(obj, engine->gt->vm, NULL);
+ if (IS_ERR(vma)) {
+ i915_gem_object_put(obj);
+ return ERR_CAST(vma);
+ }
+
+ vma->private = intel_context_create(engine); /* dummy residuals */
+ if (IS_ERR(vma->private)) {
+ vma->private = NULL;
+ i915_gem_object_put(obj);
+ return ERR_CAST(vma->private);
+ }
+
+ return vma;
+}
+
int intel_ring_submission_setup(struct intel_engine_cs *engine)
{
+ struct i915_gem_ww_ctx ww;
struct intel_timeline *timeline;
struct intel_ring *ring;
+ struct i915_vma *gen7_wa_vma;
int err;

setup_common(engine);
@@ -1270,43 +1290,68 @@ int intel_ring_submission_setup(struct intel_engine_cs *engine)
}
GEM_BUG_ON(timeline->has_initial_breadcrumb);

- err = intel_timeline_pin(timeline, NULL);
- if (err)
- goto err_timeline;
-
ring = intel_engine_create_ring(engine, SZ_16K);
if (IS_ERR(ring)) {
err = PTR_ERR(ring);
- goto err_timeline_unpin;
+ goto err_timeline;
}

- err = intel_ring_pin(ring, NULL);
- if (err)
- goto err_ring;
-
GEM_BUG_ON(engine->legacy.ring);
engine->legacy.ring = ring;
engine->legacy.timeline = timeline;

- GEM_BUG_ON(timeline->hwsp_ggtt != engine->status_page.vma);
+ gen7_wa_vma = gen7_ctx_vma(engine);
+ if (IS_ERR(gen7_wa_vma)) {
+ err = PTR_ERR(gen7_wa_vma);
+ goto err_ring;
+ }

- if (IS_HASWELL(engine->i915) && engine->class == RENDER_CLASS) {
- err = gen7_ctx_switch_bb_init(engine);
+ i915_gem_ww_ctx_init(&ww, false);
+
+retry:
+ err = i915_gem_object_lock(timeline->hwsp_ggtt->obj, &ww);
+ if (!err && gen7_wa_vma)
+ err = i915_gem_object_lock(gen7_wa_vma->obj, &ww);
+ if (!err && engine->legacy.ring->vma->obj)
+ err = i915_gem_object_lock(engine->legacy.ring->vma->obj, &ww);
+ if (!err)
+ err = intel_timeline_pin(timeline, &ww);
+ if (!err) {
+ err = intel_ring_pin(ring, &ww);
if (err)
- goto err_ring_unpin;
+ intel_timeline_unpin(timeline);
+ }
+ GEM_BUG_ON(timeline->hwsp_ggtt != engine->status_page.vma);
+
+ if (gen7_wa_vma) {
+ err = gen7_ctx_switch_bb_init(engine, &ww, gen7_wa_vma);
+ if (err) {
+ intel_ring_unpin(ring);
+ intel_timeline_unpin(timeline);
+ }
}

+ if (err == -EDEADLK) {
+ err = i915_gem_ww_ctx_backoff(&ww);
+ if (!err)
+ goto retry;
+ }
+ i915_gem_ww_ctx_fini(&ww);
+ if (err)
+ goto err_gen7_put;
+
/* Finally, take ownership and responsibility for cleanup! */
engine->release = ring_release;

return 0;

-err_ring_unpin:
- intel_ring_unpin(ring);
+err_gen7_put:
+ if (gen7_wa_vma) {
+ intel_context_put(gen7_wa_vma->private);
+ i915_gem_object_put(gen7_wa_vma->obj);
+ }
err_ring:
intel_ring_put(ring);
-err_timeline_unpin:
- intel_timeline_unpin(timeline);
err_timeline:
intel_timeline_put(timeline);