drm/msm: Drop priv->lastctx

cur_ctx_seqno already does the same thing, but handles the edge cases
where a refcnt'd context can live after lastclose.  So let's not have
two ways to do the same thing.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Akhil P Oommen <akhilpo@codeaurora.org>
Link: https://lore.kernel.org/r/20211109181117.591148-3-robdclark@gmail.comSigned-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/adreno/a2xx_gpu.c

@@ -12,7 +12,6 @@ static bool a2xx_idle(struct msm_gpu *gpu);
 
 static void a2xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 {
-	struct msm_drm_private *priv = gpu->dev->dev_private;
 	struct msm_ringbuffer *ring = submit->ring;
 	unsigned int i;
 
@@ -23,7 +22,7 @@ static void a2xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 			break;
 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
 			/* ignore if there has not been a ctx switch: */
-			if (priv->lastctx == submit->queue->ctx)
+			if (gpu->cur_ctx_seqno == submit->queue->ctx->seqno)
 				break;
 			fallthrough;
 		case MSM_SUBMIT_CMD_BUF:

drivers/gpu/drm/msm/adreno/a3xx_gpu.c

@@ -30,7 +30,6 @@ static bool a3xx_idle(struct msm_gpu *gpu);
 
 static void a3xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 {
-	struct msm_drm_private *priv = gpu->dev->dev_private;
 	struct msm_ringbuffer *ring = submit->ring;
 	unsigned int i;
 
@@ -41,7 +40,7 @@ static void a3xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 			break;
 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
 			/* ignore if there has not been a ctx switch: */
-			if (priv->lastctx == submit->queue->ctx)
+			if (gpu->cur_ctx_seqno == submit->queue->ctx->seqno)
 				break;
 			fallthrough;
 		case MSM_SUBMIT_CMD_BUF:

drivers/gpu/drm/msm/adreno/a4xx_gpu.c

@@ -24,7 +24,6 @@ static bool a4xx_idle(struct msm_gpu *gpu);
 
 static void a4xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 {
-	struct msm_drm_private *priv = gpu->dev->dev_private;
 	struct msm_ringbuffer *ring = submit->ring;
 	unsigned int i;
 
@@ -35,7 +34,7 @@ static void a4xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 			break;
 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
 			/* ignore if there has not been a ctx switch: */
-			if (priv->lastctx == submit->queue->ctx)
+			if (gpu->cur_ctx_seqno == submit->queue->ctx->seqno)
 				break;
 			fallthrough;
 		case MSM_SUBMIT_CMD_BUF:

drivers/gpu/drm/msm/adreno/a5xx_gpu.c

@@ -65,7 +65,6 @@ void a5xx_flush(struct msm_gpu *gpu, struct msm_ringbuffer *ring,
 
 static void a5xx_submit_in_rb(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 {
-	struct msm_drm_private *priv = gpu->dev->dev_private;
 	struct msm_ringbuffer *ring = submit->ring;
 	struct msm_gem_object *obj;
 	uint32_t *ptr, dwords;
@@ -76,7 +75,7 @@ static void a5xx_submit_in_rb(struct msm_gpu *gpu, struct msm_gem_submit *submit
 		case MSM_SUBMIT_CMD_IB_TARGET_BUF:
 			break;
 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
-			if (priv->lastctx == submit->queue->ctx)
+			if (gpu->cur_ctx_seqno == submit->queue->ctx->seqno)
 				break;
 			fallthrough;
 		case MSM_SUBMIT_CMD_BUF:
@@ -126,12 +125,11 @@ static void a5xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 {
 	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
 	struct a5xx_gpu *a5xx_gpu = to_a5xx_gpu(adreno_gpu);
-	struct msm_drm_private *priv = gpu->dev->dev_private;
 	struct msm_ringbuffer *ring = submit->ring;
 	unsigned int i, ibs = 0;
 
 	if (IS_ENABLED(CONFIG_DRM_MSM_GPU_SUDO) && submit->in_rb) {
-		priv->lastctx = NULL;
+		gpu->cur_ctx_seqno = 0;
 		a5xx_submit_in_rb(gpu, submit);
 		return;
 	}
@@ -166,7 +164,7 @@ static void a5xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 		case MSM_SUBMIT_CMD_IB_TARGET_BUF:
 			break;
 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
-			if (priv->lastctx == submit->queue->ctx)
+			if (gpu->cur_ctx_seqno == submit->queue->ctx->seqno)
 				break;
 			fallthrough;
 		case MSM_SUBMIT_CMD_BUF:

drivers/gpu/drm/msm/adreno/a6xx_gpu.c

@@ -106,7 +106,7 @@ static void a6xx_set_pagetable(struct a6xx_gpu *a6xx_gpu,
 	u32 asid;
 	u64 memptr = rbmemptr(ring, ttbr0);
 
-	if (ctx->seqno == a6xx_gpu->cur_ctx_seqno)
+	if (ctx->seqno == a6xx_gpu->base.base.cur_ctx_seqno)
 		return;
 
 	if (msm_iommu_pagetable_params(ctx->aspace->mmu, &ttbr, &asid))
@@ -138,14 +138,11 @@ static void a6xx_set_pagetable(struct a6xx_gpu *a6xx_gpu,
 
 	OUT_PKT7(ring, CP_EVENT_WRITE, 1);
 	OUT_RING(ring, 0x31);
-
-	a6xx_gpu->cur_ctx_seqno = ctx->seqno;
 }
 
 static void a6xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 {
 	unsigned int index = submit->seqno % MSM_GPU_SUBMIT_STATS_COUNT;
-	struct msm_drm_private *priv = gpu->dev->dev_private;
 	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
 	struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
 	struct msm_ringbuffer *ring = submit->ring;
@@ -177,7 +174,7 @@ static void a6xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 		case MSM_SUBMIT_CMD_IB_TARGET_BUF:
 			break;
 		case MSM_SUBMIT_CMD_CTX_RESTORE_BUF:
-			if (priv->lastctx == submit->queue->ctx)
+			if (gpu->cur_ctx_seqno == submit->queue->ctx->seqno)
 				break;
 			fallthrough;
 		case MSM_SUBMIT_CMD_BUF:
@@ -1081,7 +1078,7 @@ static int hw_init(struct msm_gpu *gpu)
 	/* Always come up on rb 0 */
 	a6xx_gpu->cur_ring = gpu->rb[0];
 
-	a6xx_gpu->cur_ctx_seqno = 0;
+	gpu->cur_ctx_seqno = 0;
 
 	/* Enable the SQE_to start the CP engine */
 	gpu_write(gpu, REG_A6XX_CP_SQE_CNTL, 1);

drivers/gpu/drm/msm/adreno/a6xx_gpu.h

@@ -20,16 +20,6 @@ struct a6xx_gpu {
 
 	struct msm_ringbuffer *cur_ring;
 
-	/**
-	 * cur_ctx_seqno:
-	 *
-	 * The ctx->seqno value of the context with current pgtables
-	 * installed.  Tracked by seqno rather than pointer value to
-	 * avoid dangling pointers, and cases where a ctx can be freed
-	 * and a new one created with the same address.
-	 */
-	int cur_ctx_seqno;
-
 	struct a6xx_gmu gmu;
 
 	struct drm_gem_object *shadow_bo;

drivers/gpu/drm/msm/msm_drv.c

@@ -752,14 +752,8 @@ static void context_close(struct msm_file_private *ctx)
 
 static void msm_postclose(struct drm_device *dev, struct drm_file *file)
 {
-	struct msm_drm_private *priv = dev->dev_private;
 	struct msm_file_private *ctx = file->driver_priv;
 
-	mutex_lock(&dev->struct_mutex);
-	if (ctx == priv->lastctx)
-		priv->lastctx = NULL;
-	mutex_unlock(&dev->struct_mutex);
-
 	context_close(ctx);
 }
 

drivers/gpu/drm/msm/msm_drv.h

@@ -158,7 +158,7 @@ struct msm_drm_private {
 
 	/* when we have more than one 'msm_gpu' these need to be an array: */
 	struct msm_gpu *gpu;
-	struct msm_file_private *lastctx;
+
 	/* gpu is only set on open(), but we need this info earlier */
 	bool is_a2xx;
 	bool has_cached_coherent;

drivers/gpu/drm/msm/msm_gpu.c

@@ -763,7 +763,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 	mutex_unlock(&gpu->active_lock);
 
 	gpu->funcs->submit(gpu, submit);
-	priv->lastctx = submit->queue->ctx;
+	gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
 
 	hangcheck_timer_reset(gpu);
 }

drivers/gpu/drm/msm/msm_gpu.h

@@ -144,6 +144,17 @@ struct msm_gpu {
 	struct msm_ringbuffer *rb[MSM_GPU_MAX_RINGS];
 	int nr_rings;
 
+	/**
+	 * cur_ctx_seqno:
+	 *
+	 * The ctx->seqno value of the last context to submit rendering,
+	 * and the one with current pgtables installed (for generations
+	 * that support per-context pgtables).  Tracked by seqno rather
+	 * than pointer value to avoid dangling pointers, and cases where
+	 * a ctx can be freed and a new one created with the same address.
+	 */
+	int cur_ctx_seqno;
+
 	/*
 	 * List of GEM active objects on this gpu.  Protected by
 	 * msm_drm_private::mm_lock