From: Oded Gabbay <ogabbay@kernel.org>
Date: Thu, 13 Jan 2022 08:05:38 +0000 (+0200)
Subject: habanalabs: there is no kernel TDR in future ASICs
X-Git-Tag: microblaze-v5.19~89^2~59^2~34
X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=e24a62cb68d117858f311d14ca366a18a44120a8;p=linux-2.6-microblaze.git

habanalabs: there is no kernel TDR in future ASICs

In future ASICs, there is no kernel TDR for new workloads that are
submitted directly from user-space to the device.

Therefore, the driver can NEVER know that a workload has timed-out.

So, when the user asks us to wait for interrupt on the workload's
completion, and the wait has timed-out, it doesn't mean the workload
has timed-out. It only means the wait has timed-out, which is NOT an
error from driver's perspective.

Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
---

diff --git a/drivers/misc/habanalabs/common/command_submission.c b/drivers/misc/habanalabs/common/command_submission.c
index 2f40b937c59f..29e0549ff31d 100644
--- a/drivers/misc/habanalabs/common/command_submission.c
+++ b/drivers/misc/habanalabs/common/command_submission.c
@@ -2932,11 +2932,14 @@ static int _hl_interrupt_wait_ioctl(struct hl_device *hdev, struct hl_ctx *ctx,
 				rc = -EIO;
 				*status = HL_WAIT_CS_STATUS_ABORTED;
 			} else {
-				dev_err_ratelimited(hdev->dev, "Waiting for interrupt ID %d timedout\n",
-						interrupt->interrupt_id);
-				rc = -ETIMEDOUT;
+				/* The wait has timed-out. We don't know anything beyond that
+				 * because the workload wasn't submitted through the driver.
+				 * Therefore, from driver's perspective, the workload is still
+				 * executing.
+				 */
+				rc = 0;
+				*status = HL_WAIT_CS_STATUS_BUSY;
 			}
-			*status = HL_WAIT_CS_STATUS_BUSY;
 		}
 	}
 
@@ -3049,6 +3052,12 @@ wait_again:
 			interrupt->interrupt_id);
 		rc = -EINTR;
 	} else {
+		/* The wait has timed-out. We don't know anything beyond that
+		 * because the workload wasn't submitted through the driver.
+		 * Therefore, from driver's perspective, the workload is still
+		 * executing.
+		 */
+		rc = 0;
 		*status = HL_WAIT_CS_STATUS_BUSY;
 	}