Merge tag 'arm-dt-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

[linux-2.6-microblaze.git] / drivers / gpu / drm / i915 / gem / i915_gem_wait.c

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_wait.c b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
index 319936f..e6e01c2 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_wait.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_wait.c
@@ -9,6 +9,7 @@
 #include <linux/jiffies.h>
 
 #include "gt/intel_engine.h"
+#include "gt/intel_rps.h"
 
 #include "i915_gem_ioctls.h"
 #include "i915_gem_object.h"
@@ -31,6 +32,37 @@ i915_gem_object_wait_fence(struct dma_fence *fence,
                                      timeout);
 }
 
+static void
+i915_gem_object_boost(struct dma_resv *resv, unsigned int flags)
+{
+       struct dma_resv_iter cursor;
+       struct dma_fence *fence;
+
+       /*
+        * Prescan all fences for potential boosting before we begin waiting.
+        *
+        * When we wait, we wait on outstanding fences serially. If the
+        * dma-resv contains a sequence such as 1:1, 1:2 instead of a reduced
+        * form 1:2, then as we look at each wait in turn we see that each
+        * request is currently executing and not worthy of boosting. But if
+        * we only happen to look at the final fence in the sequence (because
+        * of request coalescing or splitting between read/write arrays by
+        * the iterator), then we would boost. As such our decision to boost
+        * or not is delicately balanced on the order we wait on fences.
+        *
+        * So instead of looking for boosts sequentially, look for all boosts
+        * upfront and then wait on the outstanding fences.
+        */
+
+       dma_resv_iter_begin(&cursor, resv,
+                           dma_resv_usage_rw(flags & I915_WAIT_ALL));
+       dma_resv_for_each_fence_unlocked(&cursor, fence)
+               if (dma_fence_is_i915(fence) &&
+                   !i915_request_started(to_request(fence)))
+                       intel_rps_boost(to_request(fence));
+       dma_resv_iter_end(&cursor);
+}
+
 static long
 i915_gem_object_wait_reservation(struct dma_resv *resv,
                                 unsigned int flags,
@@ -40,6 +72,8 @@ i915_gem_object_wait_reservation(struct dma_resv *resv,
        struct dma_fence *fence;
        long ret = timeout ?: 1;
 
+       i915_gem_object_boost(resv, flags);
+
        dma_resv_iter_begin(&cursor, resv,
                            dma_resv_usage_rw(flags & I915_WAIT_ALL));
        dma_resv_for_each_fence_unlocked(&cursor, fence) {