[PATCH v4 3/5] drm/i915: Create the locked version of the request create

[Andi Shyti]

Make version of the request creation that doesn't hold any
lock.

Signed-off-by: Andi Shyti <andi.shyti at linux.intel.com>
Cc: stable at vger.kernel.org
---
 drivers/gpu/drm/i915/i915_request.c | 46 ++++++++++++++++++++---------
 drivers/gpu/drm/i915/i915_request.h |  2 ++
 2 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index a1741c4a8cff..adbe023ffe4d 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -1029,18 +1029,11 @@ __i915_request_create(struct intel_context *ce, gfp_t gfp)
 	return ERR_PTR(ret);
 }
 
-struct i915_request *
-i915_request_create(struct intel_context *ce)
+static struct i915_request *
+__i915_request_create_locked(struct intel_context *ce)
 {
 	struct i915_request *rq;
-	struct intel_timeline *tl;
-
-	if (intel_context_throttle(ce))
-		return ERR_PTR(-EINTR);
-
-	tl = intel_context_timeline_lock(ce);
-	if (IS_ERR(tl))
-		return ERR_CAST(tl);
+	struct intel_timeline *tl = ce->timeline;
 
 	/* Move our oldest request to the slab-cache (if not in use!) */
 	rq = list_first_entry(&tl->requests, typeof(*rq), link);
@@ -1050,16 +1043,41 @@ i915_request_create(struct intel_context *ce)
 	intel_context_enter(ce);
 	rq = __i915_request_create(ce, GFP_KERNEL);
 	intel_context_exit(ce); /* active reference transferred to request */
-	if (IS_ERR(rq))
-		goto err_unlock;
 
 	/* Check that we do not interrupt ourselves with a new request */
 	rq->cookie = lockdep_pin_lock(&tl->mutex);
 
 	return rq;
+}
+
+struct i915_request *
+i915_request_create_locked(struct intel_context *ce)
+{
+	intel_context_assert_timeline_is_locked(ce->timeline);
+
+	if (intel_context_throttle(ce))
+		return ERR_PTR(-EINTR);
+
+	return __i915_request_create_locked(ce);
+}
+
+struct i915_request *
+i915_request_create(struct intel_context *ce)
+{
+	struct i915_request *rq;
+	struct intel_timeline *tl;
+
+	if (intel_context_throttle(ce))
+		return ERR_PTR(-EINTR);
+
+	tl = intel_context_timeline_lock(ce);
+	if (IS_ERR(tl))
+		return ERR_CAST(tl);
+
+	rq = __i915_request_create_locked(ce);
+	if (IS_ERR(rq))
+		intel_context_timeline_unlock(tl);
 
-err_unlock:
-	intel_context_timeline_unlock(tl);
 	return rq;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_request.h b/drivers/gpu/drm/i915/i915_request.h
index f5e1bb5e857a..bb48bd4605c0 100644
--- a/drivers/gpu/drm/i915/i915_request.h
+++ b/drivers/gpu/drm/i915/i915_request.h
@@ -374,6 +374,8 @@ struct i915_request * __must_check
 __i915_request_create(struct intel_context *ce, gfp_t gfp);
 struct i915_request * __must_check
 i915_request_create(struct intel_context *ce);
+struct i915_request * __must_check
+i915_request_create_locked(struct intel_context *ce);
 
 void __i915_request_skip(struct i915_request *rq);
 bool i915_request_set_error_once(struct i915_request *rq, int error);
-- 
2.39.2