Handle persistent (VM_BIND) mappings during the request submission
in the execbuf3 path.

Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathap...@intel.com>
Signed-off-by: Andi Shyti <andi.sh...@linux.intel.com>
---
 .../gpu/drm/i915/gem/i915_gem_execbuffer3.c   | 188 +++++++++++++++++-
 1 file changed, 187 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer3.c 
b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer3.c
index 92af88bc8deb..1aeeff5e8540 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer3.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer3.c
@@ -19,6 +19,7 @@
 #include "i915_gem_vm_bind.h"
 #include "i915_trace.h"
 
+#define __EXEC3_HAS_PIN                        BIT_ULL(33)
 #define __EXEC3_ENGINE_PINNED          BIT_ULL(32)
 #define __EXEC3_INTERNAL_FLAGS         (~0ull << 32)
 
@@ -42,7 +43,9 @@
  * execlist. Hence, no support for implicit sync.
  *
  * The new execbuf3 ioctl only works in VM_BIND mode and the VM_BIND mode only
- * works with execbuf3 ioctl for submission.
+ * works with execbuf3 ioctl for submission. All BOs mapped on that VM (through
+ * VM_BIND call) at the time of execbuf3 call are deemed required for that
+ * submission.
  *
  * The execbuf3 ioctl directly specifies the batch addresses instead of as
  * object handles as in execbuf2 ioctl. The execbuf3 ioctl will also not
@@ -58,6 +61,13 @@
  * So, a lot of code supporting execbuf2 ioctl, like relocations, VA evictions,
  * vma lookup table, implicit sync, vma active reference tracking etc., are not
  * applicable for execbuf3 ioctl.
+ *
+ * During each execbuf submission, request fence is added to all VM_BIND mapped
+ * objects with DMA_RESV_USAGE_BOOKKEEP. The DMA_RESV_USAGE_BOOKKEEP usage will
+ * prevent over sync (See enum dma_resv_usage). Note that DRM_I915_GEM_WAIT and
+ * DRM_I915_GEM_BUSY ioctls do not check for DMA_RESV_USAGE_BOOKKEEP usage and
+ * hence should not be used for end of batch check. Instead, the execbuf3
+ * timeline out fence should be used for end of batch check.
  */
 
 /**
@@ -127,6 +137,23 @@ eb_find_vma(struct i915_address_space *vm, u64 addr)
        return i915_gem_vm_bind_lookup_vma(vm, va);
 }
 
+static void eb_scoop_unbound_vma_all(struct i915_address_space *vm)
+{
+       struct i915_vma *vma, *vn;
+
+       /**
+        * Move all unbound vmas back into vm_bind_list so that they are
+        * revalidated.
+        */
+       spin_lock(&vm->vm_rebind_lock);
+       list_for_each_entry_safe(vma, vn, &vm->vm_rebind_list, vm_rebind_link) {
+               list_del_init(&vma->vm_rebind_link);
+               if (!list_empty(&vma->vm_bind_link))
+                       list_move_tail(&vma->vm_bind_link, &vm->vm_bind_list);
+       }
+       spin_unlock(&vm->vm_rebind_lock);
+}
+
 static int eb_lookup_vma_all(struct i915_execbuffer *eb)
 {
        unsigned int i, current_batch = 0;
@@ -141,14 +168,121 @@ static int eb_lookup_vma_all(struct i915_execbuffer *eb)
                ++current_batch;
        }
 
+       eb_scoop_unbound_vma_all(eb->context->vm);
+
+       return 0;
+}
+
+static int eb_lock_vma_all(struct i915_execbuffer *eb)
+{
+       struct i915_address_space *vm = eb->context->vm;
+       struct i915_vma *vma;
+       int err;
+
+       err = i915_gem_object_lock(eb->context->vm->root_obj, &eb->ww);
+       if (err)
+               return err;
+
+       list_for_each_entry(vma, &vm->non_priv_vm_bind_list,
+                           non_priv_vm_bind_link) {
+               err = i915_gem_object_lock(vma->obj, &eb->ww);
+               if (err)
+                       return err;
+       }
+
        return 0;
 }
 
+static void eb_release_persistent_vma_all(struct i915_execbuffer *eb,
+                                         bool final)
+{
+       struct i915_address_space *vm = eb->context->vm;
+       struct i915_vma *vma, *vn;
+
+       lockdep_assert_held(&vm->vm_bind_lock);
+
+       if (!(eb->args->flags & __EXEC3_HAS_PIN))
+               return;
+
+       assert_object_held(vm->root_obj);
+
+       list_for_each_entry(vma, &vm->vm_bind_list, vm_bind_link)
+               __i915_vma_unpin(vma);
+
+       eb->args->flags &= ~__EXEC3_HAS_PIN;
+       if (!final)
+               return;
+
+       list_for_each_entry_safe(vma, vn, &vm->vm_bind_list, vm_bind_link)
+               if (i915_vma_verify_bind_complete(vma))
+                       list_move_tail(&vma->vm_bind_link, &vm->vm_bound_list);
+}
+
 static void eb_release_vma_all(struct i915_execbuffer *eb, bool final)
 {
+       eb_release_persistent_vma_all(eb, final);
        eb_unpin_engine(eb);
 }
 
+static int eb_reserve_fence_for_persistent_vma_all(struct i915_execbuffer *eb)
+{
+       struct i915_address_space *vm = eb->context->vm;
+       struct i915_vma *vma;
+       int ret;
+
+       ret = dma_resv_reserve_fences(vm->root_obj->base.resv, 1);
+       if (ret)
+               return ret;
+
+       list_for_each_entry(vma, &vm->non_priv_vm_bind_list,
+                           non_priv_vm_bind_link) {
+               ret = dma_resv_reserve_fences(vma->obj->base.resv, 1);
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+}
+
+static int eb_validate_persistent_vma_all(struct i915_execbuffer *eb)
+{
+       struct i915_address_space *vm = eb->context->vm;
+       struct i915_vma *vma, *last_pinned_vma = NULL;
+       int ret = 0;
+
+       lockdep_assert_held(&vm->vm_bind_lock);
+       assert_object_held(vm->root_obj);
+
+       ret = eb_reserve_fence_for_persistent_vma_all(eb);
+       if (ret)
+               return ret;
+
+       if (list_empty(&vm->vm_bind_list))
+               return 0;
+
+       list_for_each_entry(vma, &vm->vm_bind_list, vm_bind_link) {
+               u64 pin_flags = vma->start | PIN_OFFSET_FIXED | PIN_USER;
+
+               ret = i915_vma_pin_ww(vma, &eb->ww, 0, 0, pin_flags);
+               if (ret)
+                       break;
+
+               last_pinned_vma = vma;
+       }
+
+       if (ret && last_pinned_vma) {
+               list_for_each_entry(vma, &vm->vm_bind_list, vm_bind_link) {
+                       __i915_vma_unpin(vma);
+                       if (vma == last_pinned_vma)
+                               break;
+               }
+       } else if (last_pinned_vma) {
+               eb->args->flags |= __EXEC3_HAS_PIN;
+       }
+
+       return ret;
+}
+
 /*
  * Using two helper loops for the order of which requests / batches are created
  * and added the to backend. Requests are created in order from the parent to
@@ -161,8 +295,43 @@ static void eb_release_vma_all(struct i915_execbuffer *eb, 
bool final)
 #define for_each_batch_create_order(_eb) \
        for (unsigned int i = 0; i < (_eb)->num_batches; ++i)
 
+static void __eb_persistent_add_shared_fence(struct drm_i915_gem_object *obj,
+                                            struct dma_fence *fence)
+{
+       dma_resv_add_fence(obj->base.resv, fence, DMA_RESV_USAGE_BOOKKEEP);
+       obj->write_domain = 0;
+       obj->read_domains |= I915_GEM_GPU_DOMAINS;
+       obj->mm.dirty = true;
+}
+
+static void eb_persistent_add_shared_fence(struct i915_execbuffer *eb)
+{
+       struct i915_address_space *vm = eb->context->vm;
+       struct dma_fence *fence;
+       struct i915_vma *vma;
+
+       fence = eb->composite_fence ? eb->composite_fence :
+               &eb->requests[0]->fence;
+
+       __eb_persistent_add_shared_fence(vm->root_obj, fence);
+       list_for_each_entry(vma, &vm->non_priv_vm_bind_list,
+                           non_priv_vm_bind_link)
+               __eb_persistent_add_shared_fence(vma->obj, fence);
+}
+
+static void eb_move_all_persistent_vma_to_active(struct i915_execbuffer *eb)
+{
+       /* Add fence to BOs dma-resv fence list */
+       eb_persistent_add_shared_fence(eb);
+}
+
 static int eb_move_to_gpu(struct i915_execbuffer *eb)
 {
+       lockdep_assert_held(&eb->context->vm->vm_bind_lock);
+       assert_object_held(eb->context->vm->root_obj);
+
+       eb_move_all_persistent_vma_to_active(eb);
+
        /* Unconditionally flush any chipset caches (for streaming writes). */
        intel_gt_chipset_flush(eb->gt);
 
@@ -478,6 +647,7 @@ i915_gem_do_execbuffer(struct drm_device *dev,
 
        mutex_lock(&eb.context->vm->vm_bind_lock);
 
+lookup_vmas:
        err = eb_lookup_vma_all(&eb);
        if (err) {
                eb_release_vma_all(&eb, true);
@@ -494,6 +664,22 @@ i915_gem_do_execbuffer(struct drm_device *dev,
        /* only throttle once, even if we didn't need to throttle */
        throttle = false;
 
+       err = eb_lock_vma_all(&eb);
+       if (err)
+               goto err_validate;
+
+       /**
+        * No object unbinds possible once the objects are locked. So,
+        * check for any unbinds here, which needs to be scooped up.
+        */
+       if (!list_empty(&eb.context->vm->vm_rebind_list)) {
+               eb_release_vma_all(&eb, true);
+               i915_gem_ww_ctx_fini(&eb.ww);
+               goto lookup_vmas;
+       }
+
+       err = eb_validate_persistent_vma_all(&eb);
+
 err_validate:
        if (err == -EDEADLK) {
                eb_release_vma_all(&eb, false);
-- 
2.21.0.rc0.32.g243a4c7e27

Reply via email to