habanalabs: get multiple fences under same cs_lock

To add proper support for wait-for-multi-CS, locking the CS lock
for each CS fence in the list is not efficient.

Instead, this patch add support to lock the CS lock once to get all
required fences.

Signed-off-by: Ohad Sharabi <osharabi@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

1 files changed, 44 insertions, 9 deletions

diff --git a/drivers/misc/habanalabs/common/context.c b/drivers/misc/habanalabs/common/context.c
index 19b6b045219e..1001c65c5e7a 100644
--- a/drivers/misc/habanalabs/common/context.c
+++ b/drivers/misc/habanalabs/common/context.c
@@ -229,31 +229,66 @@ int hl_ctx_put(struct hl_ctx *ctx)
 	return kref_put(&ctx->refcount, hl_ctx_do_release);
 }
 
-struct hl_fence *hl_ctx_get_fence(struct hl_ctx *ctx, u64 seq)
+/* this function shall be called with cs_lock locked */
+static struct hl_fence *hl_ctx_get_fence_locked(struct hl_ctx *ctx, u64 seq)
 {
 	struct asic_fixed_properties *asic_prop = &ctx->hdev->asic_prop;
 	struct hl_fence *fence;
 
-	spin_lock(&ctx->cs_lock);
-
-	if (seq >= ctx->cs_sequence) {
-		spin_unlock(&ctx->cs_lock);
+	if (seq >= ctx->cs_sequence)
 		return ERR_PTR(-EINVAL);
-	}
 
-	if (seq + asic_prop->max_pending_cs < ctx->cs_sequence) {
-		spin_unlock(&ctx->cs_lock);
+	if (seq + asic_prop->max_pending_cs < ctx->cs_sequence)
 		return NULL;
-	}
 
 	fence = ctx->cs_pending[seq & (asic_prop->max_pending_cs - 1)];
 	hl_fence_get(fence);
+	return fence;
+}
+
+struct hl_fence *hl_ctx_get_fence(struct hl_ctx *ctx, u64 seq)
+{
+	struct hl_fence *fence;
+
+	spin_lock(&ctx->cs_lock);
+
+	fence = hl_ctx_get_fence_locked(ctx, seq);
 
 	spin_unlock(&ctx->cs_lock);
 
 	return fence;
 }
 
+int hl_ctx_get_fences(struct hl_ctx *ctx, u64 *seq_arr,
+				struct hl_fence **fence, u32 arr_len)
+{
+	struct hl_fence **fence_arr_base = fence;
+	int i, rc = 0;
+
+	spin_lock(&ctx->cs_lock);
+
+	for (i = 0; i < arr_len; i++, fence++) {
+		u64 seq = seq_arr[i];
+
+		*fence = hl_ctx_get_fence_locked(ctx, seq);
+
+		if (IS_ERR(*fence)) {
+			dev_err(ctx->hdev->dev,
+				"Failed to get fence for CS with seq 0x%llx\n",
+					seq);
+			rc = PTR_ERR(*fence);
+			break;
+		}
+	}
+
+	spin_unlock(&ctx->cs_lock);
+
+	if (rc)
+		hl_fences_put(fence_arr_base, i);
+
+	return rc;
+}
+
 /*
  * hl_ctx_mgr_init - initialize the context manager
  *