drm/i915: Use same test for eviction and submitting kernel context

During evict, we wish to idle the GPU if we see that the GGTT is full.
However, our test for idle in i915_gem_evict_something() and in
i915_gem_switch_to_kernel_context() do not match leading to
disappointment - we never believe that we are idle and keep trying to
flush the GGTT ad infinitum.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103438
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171024220855.30155-2-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 5bf96a258509989e26b1ea4397ad8f8e7ffd9d81..4f26f80b1b3eb7dbec415800e7c61956ebc09929 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -897,7 +897,7 @@ int i915_switch_context(struct drm_i915_gem_request *req)
        return do_rcs_switch(req);
 }
 
-static bool engine_has_kernel_context(struct intel_engine_cs *engine)
+static bool engine_has_idle_kernel_context(struct intel_engine_cs *engine)
 {
        struct i915_gem_timeline *timeline;
 
@@ -913,8 +913,7 @@ static bool engine_has_kernel_context(struct intel_engine_cs *engine)
                        return false;
        }
 
-       return (!engine->last_retired_context ||
-               i915_gem_context_is_kernel(engine->last_retired_context));
+       return intel_engine_has_kernel_context(engine);
 }
 
 int i915_gem_switch_to_kernel_context(struct drm_i915_private *dev_priv)
@@ -931,7 +930,7 @@ int i915_gem_switch_to_kernel_context(struct drm_i915_private *dev_priv)
                struct drm_i915_gem_request *req;
                int ret;
 
-               if (engine_has_kernel_context(engine))
+               if (engine_has_idle_kernel_context(engine))
                        continue;
 
                req = i915_gem_request_alloc(engine, dev_priv->kernel_context);

diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
index a6b769994d8df6cbdc834a608162fe320c7dd830..60ca4f05ae94a2f73c3f2b8dcf7a63f9b9bbf8f7 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -46,7 +46,7 @@ static bool ggtt_is_idle(struct drm_i915_private *i915)
               return false;
 
        for_each_engine(engine, i915, id) {
-              if (engine->last_retired_context != i915->kernel_context)
+              if (!intel_engine_has_kernel_context(engine))
                       return false;
        }
 
@@ -73,6 +73,7 @@ static int ggtt_flush(struct drm_i915_private *i915)
        if (err)
                return err;
 
+       GEM_BUG_ON(!ggtt_is_idle(i915));
        return 0;
 }
 

diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c
index ab5bf4e2e28e21f3daa7072a37cb6895aba8233c..f6cdc50d423710b2a480d03c59ef67a3718c763f 100644 (file)
--- a/drivers/gpu/drm/i915/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/intel_engine_cs.c
@@ -1585,6 +1585,12 @@ bool intel_engines_are_idle(struct drm_i915_private *dev_priv)
        return true;
 }
 
+bool intel_engine_has_kernel_context(const struct intel_engine_cs *engine)
+{
+       return (!engine->last_retired_context ||
+               i915_gem_context_is_kernel(engine->last_retired_context));
+}
+
 void intel_engines_reset_default_submission(struct drm_i915_private *i915)
 {
        struct intel_engine_cs *engine;

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 6a42ed618a28ce1f47b2aeca7263cb9f561a1a86..a2589aa891639db6d46cb6126ebb58cabb1fd35b 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -866,6 +866,8 @@ static inline u32 *gen8_emit_pipe_control(u32 *batch, u32 flags, u32 offset)
 bool intel_engine_is_idle(struct intel_engine_cs *engine);
 bool intel_engines_are_idle(struct drm_i915_private *dev_priv);
 
+bool intel_engine_has_kernel_context(const struct intel_engine_cs *engine);
+
 void intel_engines_mark_idle(struct drm_i915_private *i915);
 void intel_engines_reset_default_submission(struct drm_i915_private *i915);