drm/i915: put context upon switching

In order to be notified of when the context and all of its associated
objects is idle (for if the context maps to a ppgtt) we need a callback
from the retire handler. We can arrange this by using the kref_get/put
of the context for request tracking and by inserting a request to
demarque the switch away from the old context.

[Ben: fixed minor error to patch compile, AND s/last_context/from/]
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Chris Wilson 2013-05-02 16:48:07 +03:00 committed by Daniel Vetter
parent 21a8e6a485
commit 112522f678
2 changed files with 25 additions and 14 deletions

View File

@ -361,13 +361,13 @@ mi_set_context(struct intel_ring_buffer *ring,
static int do_switch(struct i915_hw_context *to)
{
struct intel_ring_buffer *ring = to->ring;
struct drm_i915_gem_object *from_obj = ring->last_context_obj;
struct i915_hw_context *from = ring->last_context;
u32 hw_flags = 0;
int ret;
BUG_ON(from_obj != NULL && from_obj->pin_count == 0);
BUG_ON(from != NULL && from->obj != NULL && from->obj->pin_count == 0);
if (from_obj == to->obj)
if (from == to)
return 0;
ret = i915_gem_object_pin(to->obj, CONTEXT_ALIGN, false, false);
@ -390,7 +390,7 @@ static int do_switch(struct i915_hw_context *to)
if (!to->is_initialized || is_default_context(to))
hw_flags |= MI_RESTORE_INHIBIT;
else if (WARN_ON_ONCE(from_obj == to->obj)) /* not yet expected */
else if (WARN_ON_ONCE(from == to)) /* not yet expected */
hw_flags |= MI_FORCE_RESTORE;
ret = mi_set_context(ring, to, hw_flags);
@ -405,9 +405,9 @@ static int do_switch(struct i915_hw_context *to)
* is a bit suboptimal because the retiring can occur simply after the
* MI_SET_CONTEXT instead of when the next seqno has completed.
*/
if (from_obj != NULL) {
from_obj->base.read_domains = I915_GEM_DOMAIN_INSTRUCTION;
i915_gem_object_move_to_active(from_obj, ring);
if (from != NULL) {
from->obj->base.read_domains = I915_GEM_DOMAIN_INSTRUCTION;
i915_gem_object_move_to_active(from->obj, ring);
/* As long as MI_SET_CONTEXT is serializing, ie. it flushes the
* whole damn pipeline, we don't need to explicitly mark the
* object dirty. The only exception is that the context must be
@ -415,15 +415,26 @@ static int do_switch(struct i915_hw_context *to)
* able to defer doing this until we know the object would be
* swapped, but there is no way to do that yet.
*/
from_obj->dirty = 1;
BUG_ON(from_obj->ring != ring);
i915_gem_object_unpin(from_obj);
from->obj->dirty = 1;
BUG_ON(from->obj->ring != ring);
drm_gem_object_unreference(&from_obj->base);
ret = i915_add_request(ring, NULL, NULL);
if (ret) {
/* Too late, we've already scheduled a context switch.
* Try to undo the change so that the hw state is
* consistent with out tracking. In case of emergency,
* scream.
*/
WARN_ON(mi_set_context(ring, from, MI_RESTORE_INHIBIT));
return ret;
}
i915_gem_object_unpin(from->obj);
i915_gem_context_unreference(from);
}
drm_gem_object_reference(&to->obj->base);
ring->last_context_obj = to->obj;
i915_gem_context_reference(to);
ring->last_context = to;
to->is_initialized = true;
return 0;

View File

@ -135,7 +135,7 @@ struct intel_ring_buffer {
*/
bool itlb_before_ctx_switch;
struct i915_hw_context *default_context;
struct drm_i915_gem_object *last_context_obj;
struct i915_hw_context *last_context;
void *private;
};