From 0009e46cd54324c4af20b0b52b89973b1b914167 Mon Sep 17 00:00:00 2001 From: Ben Widawsky Date: Fri, 6 Dec 2013 14:11:02 -0800 Subject: [PATCH] drm/i915: Track which ring a context ran on Previously we dropped the association of a context to a ring. It is however very important to know which ring a context ran on (we could have reused the other member, but I was nitpicky). This is very important when we switch address spaces, which unlike context objects, do change per ring. As an example, if we have: RCS BCS ctx A ctx A ctx B ctx B Without tracking the last ring B ran on, we wouldn't know to switch the address space on BCS in the last row. As a result, we no longer need to track which ring a context "belongs" to, as it never really made much sense anyway. Signed-off-by: Ben Widawsky Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_drv.h | 2 +- drivers/gpu/drm/i915/i915_gem_context.c | 12 +++++------- 2 files changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 2c0115edc69f..2b16c29ea571 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -696,7 +696,7 @@ struct i915_hw_context { bool is_initialized; uint8_t remap_slice; struct drm_i915_file_private *file_priv; - struct intel_ring_buffer *ring; + struct intel_ring_buffer *last_ring; struct drm_i915_gem_object *obj; struct i915_ctx_hang_stats hang_stats; diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index 7a5311c3225a..5f8bc06e8594 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -176,11 +176,6 @@ create_hw_context(struct drm_device *dev, goto err_out; } - /* The ring associated with the context object is handled by the normal - * object tracking code. We give an initial ring value simple to pass an - * assertion in the context switch code. - */ - ctx->ring = &dev_priv->ring[RCS]; list_add_tail(&ctx->link, &dev_priv->context_list); /* Default context will never have a file_priv */ @@ -208,7 +203,8 @@ err_out: static inline bool is_default_context(struct i915_hw_context *ctx) { - return (ctx == ctx->ring->default_context); + /* Cheap trick to determine default contexts */ + return ctx->file_priv ? false : true; } /** @@ -338,6 +334,7 @@ void i915_gem_context_fini(struct drm_device *dev) i915_gem_context_unreference(ring->last_context); ring->default_context = NULL; + ring->last_context = NULL; } i915_gem_object_ggtt_unpin(dctx->obj); @@ -467,7 +464,7 @@ static int do_switch(struct intel_ring_buffer *ring, BUG_ON(!i915_gem_obj_is_pinned(from->obj)); } - if (from == to && !to->remap_slice) + if (from == to && from->last_ring == ring && !to->remap_slice) return 0; if (ring != &dev_priv->ring[RCS]) { @@ -547,6 +544,7 @@ done: i915_gem_context_reference(to); ring->last_context = to; to->is_initialized = true; + to->last_ring = ring; return 0; }