Re: [PATCH v9 11/26] drm/xe/devcoredump: Update handling of xe_force_wake_get return

["Nilawar, Badal" <badal.nilawar@intel.com>]

On 14-10-2024 13:25, Himal Prasad Ghimiray wrote:
> xe_force_wake_get() now returns the reference count-incremented domain
> mask. If it fails for individual domains, the return value will always
> be 0. However, for XE_FORCEWAKE_ALL, it may return a non-zero value even
> in the event of failure. Use helper xe_force_wake_ref_has_domain to
> verify all domains are initialized or not. Update the return handling of
> xe_force_wake_get() to reflect this behavior, and ensure that the return
> value is passed as input to xe_force_wake_put().
> 
> v3
> - return xe_wakeref_t instead of int in xe_force_wake_get()
> 
> v5
> - return unsigned int for xe_force_wake_get()
> 
> v6
> - use helper xe_force_wake_ref_has_domain()
> 
> v7
> - Fix commit message
> 
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
> Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> ---
>   drivers/gpu/drm/xe/xe_devcoredump.c | 14 ++++++++------
>   1 file changed, 8 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_devcoredump.c b/drivers/gpu/drm/xe/xe_devcoredump.c
> index 99842a35dbf0..8b0ea77661b2 100644
> --- a/drivers/gpu/drm/xe/xe_devcoredump.c
> +++ b/drivers/gpu/drm/xe/xe_devcoredump.c
> @@ -158,13 +158,15 @@ static void xe_devcoredump_deferred_snap_work(struct work_struct *work)
>   {
>   	struct xe_devcoredump_snapshot *ss = container_of(work, typeof(*ss), work);
>   	struct xe_devcoredump *coredump = container_of(ss, typeof(*coredump), snapshot);
> +	unsigned int fw_ref;
>   
>   	/* keep going if fw fails as we still want to save the memory and SW data */
> -	if (xe_force_wake_get(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL))
> +	fw_ref = xe_force_wake_get(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL);
> +	if (!xe_force_wake_ref_has_domain(fw_ref, XE_FORCEWAKE_ALL))
>   		xe_gt_info(ss->gt, "failed to get forcewake for coredump capture\n");
>   	xe_vm_snapshot_capture_delayed(ss->vm);
>   	xe_guc_exec_queue_snapshot_capture_delayed(ss->ge);
> -	xe_force_wake_put(gt_to_fw(ss->gt), XE_FORCEWAKE_ALL);
> +	xe_force_wake_put(gt_to_fw(ss->gt), fw_ref);
>   
>   	/* Calculate devcoredump size */
>   	ss->read.size = __xe_devcoredump_read(NULL, INT_MAX, coredump);
> @@ -236,8 +238,9 @@ static void devcoredump_snapshot(struct xe_devcoredump *coredump,
>   	u32 width_mask = (0x1 << q->width) - 1;
>   	const char *process_name = "no process";
>   
> -	int i;
> +	unsigned int fw_ref;
>   	bool cookie;
> +	int i;
>   
>   	ss->snapshot_time = ktime_get_real();
>   	ss->boot_time = ktime_get_boottime();
> @@ -261,8 +264,7 @@ static void devcoredump_snapshot(struct xe_devcoredump *coredump,
>   	}
>   
>   	/* keep going if fw fails as we still want to save the memory and SW data */
> -	if (xe_force_wake_get(gt_to_fw(q->gt), XE_FORCEWAKE_ALL))
> -		xe_gt_info(ss->gt, "failed to get forcewake for coredump capture\n");
> +	fw_ref = xe_force_wake_get(gt_to_fw(q->gt), XE_FORCEWAKE_ALL);
>   
>   	ss->guc.log = xe_guc_log_snapshot_capture(&guc->log, true);
>   	ss->guc.ct = xe_guc_ct_snapshot_capture(&guc->ct, true);
> @@ -274,7 +276,7 @@ static void devcoredump_snapshot(struct xe_devcoredump *coredump,
>   
>   	queue_work(system_unbound_wq, &ss->work);
>   
> -	xe_force_wake_put(gt_to_fw(q->gt), XE_FORCEWAKE_ALL);
> +	xe_force_wake_put(gt_to_fw(q->gt), fw_ref);

LGTM
Reviewed-by: Badal Nilawar <badal.nilawar@intel.com>

Regards,
Badal

>   	dma_fence_end_signalling(cookie);
>   }
>