[PATCH 31/74] drm/i915: Pull wait-for-idle into i915_gem_switch_to_kernel_context()

[Chris Wilson]

All callers do want a synchronous switch to the kernel context, that is
by the time the call returns, the GPU has evicted all user contexts and
now has the kernel context pinned. As all callers want this behaviour,
refactor the common wait-for-idle into the switch.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c         |  6 ------
 drivers/gpu/drm/i915/i915_gem_context.c |  4 +++-
 drivers/gpu/drm/i915/i915_gem_evict.c   | 14 +-------------
 3 files changed, 4 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index a5d1a4a9a011..6c40f2b0157e 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4690,12 +4690,6 @@ int i915_gem_suspend(struct drm_i915_private *dev_priv)
 	 * not rely on its state.
 	 */
 	ret = i915_gem_switch_to_kernel_context(dev_priv);
-	if (ret)
-		goto err_unlock;
-
-	ret = i915_gem_wait_for_idle(dev_priv,
-				     I915_WAIT_INTERRUPTIBLE |
-				     I915_WAIT_LOCKED);
 	if (ret && ret != -EIO)
 		goto err_unlock;
 
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 58a2a44f88bd..f70b05e682ac 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -924,7 +924,9 @@ int i915_gem_switch_to_kernel_context(struct drm_i915_private *dev_priv)
 			return ret;
 	}
 
-	return 0;
+	return i915_gem_wait_for_idle(dev_priv,
+				     I915_WAIT_INTERRUPTIBLE |
+				     I915_WAIT_LOCKED);
 }
 
 static bool client_is_banned(struct drm_i915_file_private *file_priv)
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
index a5a5b7e6daae..03cfde259b45 100644
--- a/drivers/gpu/drm/i915/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -52,25 +52,13 @@ static bool ggtt_is_idle(struct drm_i915_private *dev_priv)
 
 static int ggtt_flush(struct drm_i915_private *i915)
 {
-	int err;
-
 	/* Not everything in the GGTT is tracked via vma (otherwise we
 	 * could evict as required with minimal stalling) so we are forced
 	 * to idle the GPU and explicitly retire outstanding requests in
 	 * the hopes that we can then remove contexts and the like only
 	 * bound by their active reference.
 	 */
-	err = i915_gem_switch_to_kernel_context(i915);
-	if (err)
-		return err;
-
-	err = i915_gem_wait_for_idle(i915,
-				     I915_WAIT_INTERRUPTIBLE |
-				     I915_WAIT_LOCKED);
-	if (err)
-		return err;
-
-	return 0;
+	return i915_gem_switch_to_kernel_context(i915);
 }
 
 static bool
-- 
2.14.1