2019-07-18 06:31:57

by Oded Gabbay

Subject: [PATCH] habanalabs: add debug print when rejecting CS

When rejecting CS because of too many in-flight CS, print a debug message
about it as it useful to know when the user is debugging (it indicates a
back-pressure from the driver as the device is not fast enough to consume
the CS)

Signed-off-by: Oded Gabbay <[email protected]>
---
drivers/misc/habanalabs/command_submission.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/misc/habanalabs/command_submission.c b/drivers/misc/habanalabs/command_submission.c
index 6ad83d5ef4b0..f4e2c2ad0057 100644
--- a/drivers/misc/habanalabs/command_submission.c
+++ b/drivers/misc/habanalabs/command_submission.c
@@ -305,6 +305,8 @@ static int allocate_cs(struct hl_device *hdev, struct hl_ctx *ctx,
other = ctx->cs_pending[fence->cs_seq & (HL_MAX_PENDING_CS - 1)];
if ((other) && (!dma_fence_is_signaled(other))) {
spin_unlock(&ctx->cs_lock);
+ dev_dbg(hdev->dev,
+ "Rejecting CS because of too many in-flights CS\n");
rc = -EAGAIN;
goto free_fence;
}
--
2.17.1

2019-07-18 06:43:59

by Omer Shpigelman

Subject: RE: [PATCH] habanalabs: add debug print when rejecting CS

From: Oded Gabbay <[email protected]>
Sent: Thursday, 18 July 2019 9:30

> When rejecting CS because of too many in-flight CS, print a debug message
> about it as it useful to know when the user is debugging (it indicates a back-
> pressure from the driver as the device is not fast enough to consume the CS)
>
> Signed-off-by: Oded Gabbay <[email protected]>

Reviewed-by: Omer Shpigelman <[email protected]>