drm/msm/gem: Split out submit_unpin_objects() helper

Untangle unpinning from unlock/unref loop.  The unpin only happens in
error paths so it is easier to decouple from the normal unlock path.

Since we never have an intermediate state where a subset of buffers
are pinned (ie. we never bail out of the pin or unpin loops) we can
replace the bo state flag bit with a global flag in the submit.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/568335/

drivers/gpu/drm/msm/msm_gem.h

@@ -274,8 +274,9 @@ struct msm_gem_submit {
 	int fence_id;       /* key into queue->fence_idr */
 	struct msm_gpu_submitqueue *queue;
 	struct pid *pid;    /* submitting process */
-	bool fault_dumped;  /* Limit devcoredump dumping to one per submit */
-	bool in_rb;         /* "sudo" mode, copy cmds into RB */
+	bool bos_pinned : 1;
+	bool fault_dumped:1;/* Limit devcoredump dumping to one per submit */
+	bool in_rb : 1;     /* "sudo" mode, copy cmds into RB */
 	struct msm_ringbuffer *ring;
 	unsigned int nr_cmds;
 	unsigned int nr_bos;
@@ -292,7 +293,6 @@ struct msm_gem_submit {
 	struct {
 /* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
 #define BO_LOCKED	0x4000	/* obj lock is held */
-#define BO_PINNED	0x2000	/* obj (pages) is pinned and on active list */
 		uint32_t flags;
 		union {
 			struct drm_gem_object *obj;

drivers/gpu/drm/msm/msm_gem_submit.c

@@ -265,9 +265,6 @@ static void submit_cleanup_bo(struct msm_gem_submit *submit, int i,
 	 */
 	submit->bos[i].flags &= ~cleanup_flags;
 
-	if (flags & BO_PINNED)
-		msm_gem_unpin_locked(obj);
-
 	if (flags & BO_LOCKED)
 		dma_resv_unlock(obj->resv);
 }
@@ -407,13 +404,28 @@ static int submit_pin_objects(struct msm_gem_submit *submit)
 	mutex_lock(&priv->lru.lock);
 	for (i = 0; i < submit->nr_bos; i++) {
 		msm_gem_pin_obj_locked(submit->bos[i].obj);
-		submit->bos[i].flags |= BO_PINNED;
 	}
 	mutex_unlock(&priv->lru.lock);
 
+	submit->bos_pinned = true;
+
 	return ret;
 }
 
+static void submit_unpin_objects(struct msm_gem_submit *submit)
+{
+	if (!submit->bos_pinned)
+		return;
+
+	for (int i = 0; i < submit->nr_bos; i++) {
+		struct drm_gem_object *obj = submit->bos[i].obj;
+
+		msm_gem_unpin_locked(obj);
+	}
+
+	submit->bos_pinned = false;
+}
+
 static void submit_attach_object_fences(struct msm_gem_submit *submit)
 {
 	int i;
@@ -525,7 +537,7 @@ static void submit_cleanup(struct msm_gem_submit *submit, bool error)
 	unsigned i;
 
 	if (error)
-		cleanup_flags |= BO_PINNED;
+		submit_unpin_objects(submit);
 
 	for (i = 0; i < submit->nr_bos; i++) {
 		struct drm_gem_object *obj = submit->bos[i].obj;

drivers/gpu/drm/msm/msm_ringbuffer.c

@@ -29,9 +29,10 @@ static struct dma_fence *msm_job_run(struct drm_sched_job *job)
 		struct drm_gem_object *obj = submit->bos[i].obj;
 
 		msm_gem_unpin_active(obj);
-		submit->bos[i].flags &= ~BO_PINNED;
 	}
 
+	submit->bos_pinned = false;
+
 	mutex_unlock(&priv->lru.lock);
 
 	msm_gpu_submit(gpu, submit);