From 0cb26a8ed1a61a31a79bb9fd97687fb0a76ce221 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 24 Jun 2016 14:55:53 +0100 Subject: [PATCH] drm/i915: Move legacy kernel context pinning to intel_ringbuffer.c This is so that we have symmetry with intel_lrc.c and avoid a source of if (i915.enable_execlists) layering violation within i915_gem_context.c - that is we move the specific handling of the dev_priv->kernel_context for legacy submission into the legacy submission code. This depends upon the init/fini ordering between contexts and engines already defined by intel_lrc.c, and also exporting the context alignment required for pinning the legacy context. v2: Separate out pin/unpin context funcs for greater symmetry with intel_lrc. One more step towards unifying behaviour between the two classes of engines and towards fixing another bug in i915_switch_context vs requests. Signed-off-by: Chris Wilson Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/1466776558-21516-2-git-send-email-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_drv.h | 2 + drivers/gpu/drm/i915/i915_gem_context.c | 27 ++---------- drivers/gpu/drm/i915/intel_ringbuffer.c | 55 +++++++++++++++++++++++++ 3 files changed, 60 insertions(+), 24 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 5b68c07b3921..2b01bbc1fb6e 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -872,6 +872,8 @@ struct i915_gem_context { u32 user_handle; #define CONTEXT_NO_ZEROMAP (1<<0) + u32 ggtt_alignment; + struct intel_context { struct drm_i915_gem_object *state; struct intel_ringbuffer *ringbuf; diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index 30d9b4fd30f3..419d2551dc6b 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -268,6 +268,8 @@ __create_hw_context(struct drm_device *dev, list_add_tail(&ctx->link, &dev_priv->context_list); ctx->i915 = dev_priv; + ctx->ggtt_alignment = get_context_alignment(dev_priv); + if (dev_priv->hw_context_size) { struct drm_i915_gem_object *obj = i915_gem_alloc_context_obj(dev, dev_priv->hw_context_size); @@ -451,26 +453,6 @@ int i915_gem_context_init(struct drm_device *dev) return PTR_ERR(ctx); } - if (!i915.enable_execlists && ctx->engine[RCS].state) { - int ret; - - /* We may need to do things with the shrinker which - * require us to immediately switch back to the default - * context. This can cause a problem as pinning the - * default context also requires GTT space which may not - * be available. To avoid this we always pin the default - * context. - */ - ret = i915_gem_obj_ggtt_pin(ctx->engine[RCS].state, - get_context_alignment(dev_priv), 0); - if (ret) { - DRM_ERROR("Failed to pinned default global context (error %d)\n", - ret); - i915_gem_context_unreference(ctx); - return ret; - } - } - dev_priv->kernel_context = ctx; DRM_DEBUG_DRIVER("%s context support initialized\n", @@ -507,9 +489,6 @@ void i915_gem_context_fini(struct drm_device *dev) lockdep_assert_held(&dev->struct_mutex); - if (!i915.enable_execlists && dctx->engine[RCS].state) - i915_gem_object_ggtt_unpin(dctx->engine[RCS].state); - i915_gem_context_unreference(dctx); dev_priv->kernel_context = NULL; @@ -759,7 +738,7 @@ static int do_rcs_switch(struct drm_i915_gem_request *req) /* Trying to pin first makes error handling easier. */ ret = i915_gem_obj_ggtt_pin(to->engine[RCS].state, - get_context_alignment(engine->i915), + to->ggtt_alignment, 0); if (ret) return ret; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index fedd27049814..86b80b4727fb 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -2321,6 +2321,47 @@ intel_ringbuffer_free(struct intel_ringbuffer *ring) kfree(ring); } +static int intel_ring_context_pin(struct i915_gem_context *ctx, + struct intel_engine_cs *engine) +{ + struct intel_context *ce = &ctx->engine[engine->id]; + int ret; + + lockdep_assert_held(&ctx->i915->dev->struct_mutex); + + if (ce->pin_count++) + return 0; + + if (ce->state) { + ret = i915_gem_obj_ggtt_pin(ce->state, ctx->ggtt_alignment, 0); + if (ret) + goto error; + } + + i915_gem_context_reference(ctx); + return 0; + +error: + ce->pin_count = 0; + return ret; +} + +static void intel_ring_context_unpin(struct i915_gem_context *ctx, + struct intel_engine_cs *engine) +{ + struct intel_context *ce = &ctx->engine[engine->id]; + + lockdep_assert_held(&ctx->i915->dev->struct_mutex); + + if (--ce->pin_count) + return; + + if (ce->state) + i915_gem_object_ggtt_unpin(ce->state); + + i915_gem_context_unreference(ctx); +} + static int intel_init_ring_buffer(struct drm_device *dev, struct intel_engine_cs *engine) { @@ -2341,6 +2382,17 @@ static int intel_init_ring_buffer(struct drm_device *dev, init_waitqueue_head(&engine->irq_queue); + /* We may need to do things with the shrinker which + * require us to immediately switch back to the default + * context. This can cause a problem as pinning the + * default context also requires GTT space which may not + * be available. To avoid this we always pin the default + * context. + */ + ret = intel_ring_context_pin(dev_priv->kernel_context, engine); + if (ret) + goto error; + ringbuf = intel_engine_create_ringbuffer(engine, 32 * PAGE_SIZE); if (IS_ERR(ringbuf)) { ret = PTR_ERR(ringbuf); @@ -2408,6 +2460,9 @@ void intel_cleanup_engine(struct intel_engine_cs *engine) i915_cmd_parser_fini_ring(engine); i915_gem_batch_pool_fini(&engine->batch_pool); + + intel_ring_context_unpin(dev_priv->kernel_context, engine); + engine->i915 = NULL; } -- 2.20.1