drm/i915: intel_ring_initialized() must be simple and inline

Based on Chris Wilson's patch from 6 months ago, rebased and adapted.

The current implementation of intel_ring_initialized() is too heavyweight;
it's a non-inlined function that chases several levels of pointers. This
wouldn't matter too much if it were rarely called, but it's used inside
the iterator test of for_each_ring() and is therefore called quite
frequently. So let's make it simple and inline ...

The idea here is to use ring->dev as an indicator showing which engines
have been initialised and are therefore to be included in iterations that
use for_each_ring(). This allows us to avoid multiple memory references
and a (non-inlined) function call on each iteration of each such loop.

	Fixes regression from
	commit 48d823878d64f93163f5a949623346748bbce1b4
	Author: Oscar Mateo <oscar.mateo@intel.com>
	Date:   Thu Jul 24 17:04:23 2014 +0100

	    drm/i915/bdw: Generic logical ring init and cleanup

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449586956-32360-2-git-send-email-david.s.gordon@intel.com

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 4ebafab53f30e6492e99c0bcac6256f1f5b1c2b9..7644c48da4ea6e5ae5aabf2bcccbb5cc54dc254b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1894,8 +1894,10 @@ void intel_logical_ring_cleanup(struct intel_engine_cs *ring)
 
        dev_priv = ring->dev->dev_private;
 
-       intel_logical_ring_stop(ring);
-       WARN_ON((I915_READ_MODE(ring) & MODE_IDLE) == 0);
+       if (ring->buffer) {
+               intel_logical_ring_stop(ring);
+               WARN_ON((I915_READ_MODE(ring) & MODE_IDLE) == 0);
+       }
 
        if (ring->cleanup)
                ring->cleanup(ring);
@@ -1909,6 +1911,7 @@ void intel_logical_ring_cleanup(struct intel_engine_cs *ring)
        }
 
        lrc_destroy_wa_ctx_obj(ring);
+       ring->dev = NULL;
 }
 
 static int logical_ring_init(struct drm_device *dev, struct intel_engine_cs *ring)
@@ -1931,11 +1934,11 @@ static int logical_ring_init(struct drm_device *dev, struct intel_engine_cs *rin
 
        ret = i915_cmd_parser_init_ring(ring);
        if (ret)
-               return ret;
+               goto error;
 
        ret = intel_lr_context_deferred_alloc(ring->default_context, ring);
        if (ret)
-               return ret;
+               goto error;
 
        /* As this is the default context, always pin it */
        ret = intel_lr_context_do_pin(
@@ -1946,9 +1949,13 @@ static int logical_ring_init(struct drm_device *dev, struct intel_engine_cs *rin
                DRM_ERROR(
                        "Failed to pin and map ringbuffer %s: %d\n",
                        ring->name, ret);
-               return ret;
+               goto error;
        }
 
+       return 0;
+
+error:
+       intel_logical_ring_cleanup(ring);
        return ret;
 }
 

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index e5359ebfb1bece4aef5c7cdae021a15562155ec6..eefce9a3e9c84a625a126f4f90e0df7a3555d7c0 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -34,23 +34,6 @@
 #include "i915_trace.h"
 #include "intel_drv.h"
 
-bool
-intel_ring_initialized(struct intel_engine_cs *ring)
-{
-       struct drm_device *dev = ring->dev;
-
-       if (!dev)
-               return false;
-
-       if (i915.enable_execlists) {
-               struct intel_context *dctx = ring->default_context;
-               struct intel_ringbuffer *ringbuf = dctx->engine[ring->id].ringbuf;
-
-               return ringbuf->obj;
-       } else
-               return ring->buffer && ring->buffer->obj;
-}
-
 int __intel_ring_space(int head, int tail, int size)
 {
        int space = head - tail;
@@ -2168,8 +2151,10 @@ static int intel_init_ring_buffer(struct drm_device *dev,
        init_waitqueue_head(&ring->irq_queue);
 
        ringbuf = intel_engine_create_ringbuffer(ring, 32 * PAGE_SIZE);
-       if (IS_ERR(ringbuf))
-               return PTR_ERR(ringbuf);
+       if (IS_ERR(ringbuf)) {
+               ret = PTR_ERR(ringbuf);
+               goto error;
+       }
        ring->buffer = ringbuf;
 
        if (I915_NEED_GFX_HWS(dev)) {
@@ -2198,8 +2183,7 @@ static int intel_init_ring_buffer(struct drm_device *dev,
        return 0;
 
 error:
-       intel_ringbuffer_free(ringbuf);
-       ring->buffer = NULL;
+       intel_cleanup_ring_buffer(ring);
        return ret;
 }
 
@@ -2212,12 +2196,14 @@ void intel_cleanup_ring_buffer(struct intel_engine_cs *ring)
 
        dev_priv = to_i915(ring->dev);
 
-       intel_stop_ring_buffer(ring);
-       WARN_ON(!IS_GEN2(ring->dev) && (I915_READ_MODE(ring) & MODE_IDLE) == 0);
+       if (ring->buffer) {
+               intel_stop_ring_buffer(ring);
+               WARN_ON(!IS_GEN2(ring->dev) && (I915_READ_MODE(ring) & MODE_IDLE) == 0);
 
-       intel_unpin_ringbuffer_obj(ring->buffer);
-       intel_ringbuffer_free(ring->buffer);
-       ring->buffer = NULL;
+               intel_unpin_ringbuffer_obj(ring->buffer);
+               intel_ringbuffer_free(ring->buffer);
+               ring->buffer = NULL;
+       }
 
        if (ring->cleanup)
                ring->cleanup(ring);
@@ -2226,6 +2212,7 @@ void intel_cleanup_ring_buffer(struct intel_engine_cs *ring)
 
        i915_cmd_parser_fini_ring(ring);
        i915_gem_batch_pool_fini(&ring->batch_pool);
+       ring->dev = NULL;
 }
 
 static int ring_wait_for_space(struct intel_engine_cs *ring, int n)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 5d1eb206151ddb9451d698cbb61166bece5436c8..49574ffe54bcf8420d33290a89e67f70d8d7b945 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -350,7 +350,11 @@ struct  intel_engine_cs {
        u32 (*get_cmd_length_mask)(u32 cmd_header);
 };
 
-bool intel_ring_initialized(struct intel_engine_cs *ring);
+static inline bool
+intel_ring_initialized(struct intel_engine_cs *ring)
+{
+       return ring->dev != NULL;
+}
 
 static inline unsigned
 intel_ring_flag(struct intel_engine_cs *ring)