[PATCH] drm/amdgpu: treat negative lockup timeout as 'infinite timeout'

[Christian König]

Am 05.05.19 um 16:23 schrieb Evan Quan:
> Negative lockup timeout is valid and will be treated as
> 'infinite timeout'.
>
> Change-Id: I0d8387956a9c744073c0281ef2e1a547d4f16dec
> Signed-off-by: Evan Quan <evan.quan at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 14 ++++++++++----
>   1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 5b03e17e6e06..4d6dff6855f8 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -233,13 +233,14 @@ module_param_named(msi, amdgpu_msi, int, 0444);
>    * Set GPU scheduler timeout value in ms.
>    *
>    * The format can be [Non-Compute] or [GFX,Compute,SDMA,Video]. That is there can be one or
> - * multiple values specified. 0 and negative values are invalidated. They will be adjusted
> - * to default timeout.
> + * multiple values specified.
>    *  - With one value specified, the setting will apply to all non-compute jobs.
>    *  - With multiple values specified, the first one will be for GFX. The second one is for Compute.
>    *    And the third and fourth ones are for SDMA and Video.
>    * By default(with no lockup_timeout settings), the timeout for all non-compute(GFX, SDMA and Video)
>    * jobs is 10000. And there is no timeout enforced on compute jobs.
> + * Value 0 is invalidated, will be adjusted to default timeout settings.
> + * Negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET).
>    */
>   MODULE_PARM_DESC(lockup_timeout, "GPU lockup timeout in ms (default: 10000 for non-compute jobs and no timeout for compute jobs), "
>   		"format is [Non-Compute] or [GFX,Compute,SDMA,Video]");
> @@ -1248,11 +1249,16 @@ int amdgpu_device_get_job_timeout_settings(struct amdgpu_device *adev)
>   			if (ret)
>   				return ret;
>   
> -			/* Invalidate 0 and negative values */
> -			if (timeout <= 0) {
> +			/*
> +			 * Value 0 will be adjusted to default timeout settings.
> +			 * Negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET).
> +			 */
> +			if (!timeout) {
>   				index++;
>   				continue;
>   			}
> +			if (timeout < 0)
> +				timeout = MAX_JIFFY_OFFSET;

This is superfluous and maybe even harmful, msecs_to_jiffies() should 
take care of this conversion.

Maybe even convert the values directly here.

Christian.

>   
>   			switch (index++) {
>   			case 0: