From 112522f6789581824903f6f72082b5b841a7f0f9 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 2 May 2013 16:48:07 +0300 Subject: [PATCH] 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 Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gem_context.c | 37 ++++++++++++++++--------- drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +- 2 files changed, 25 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index 280617ef4996..efa0ede5c679 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -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); + + 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; + } - drm_gem_object_unreference(&from_obj->base); + 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; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index d66208c2c48b..dac1614a1bca 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -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; }; -- 2.20.1