Re: [PATCH 1/3] drm/xe/pf: Add _locked variant of the GGTT bulk config function

Michal Wajdeczko <[email protected]> wrote on śro [2026-sie-05 17:47:31 +0200]:
> We will soon want to provision all VFs, including their GGTT config,
> in one step. Split existing GGTT bulk configuration function into
> two functions, one of which will expect the master lock to be already
> taken. Use this new function in the fair GGTT provisioning.
> 
> Signed-off-by: Michal Wajdeczko <[email protected]>
> ---
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c | 37 ++++++++++++++++------
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h |  2 ++
>  2 files changed, 29 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> index 2c9b85b84b1b..47623315d615 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> @@ -668,7 +668,7 @@ static int pf_config_bulk_set_u64_done(struct xe_gt *gt, unsigned int first, uns
>  }
>  
>  /**
> - * xe_gt_sriov_pf_config_bulk_set_ggtt - Provision many VFs with GGTT.
> + * xe_gt_sriov_pf_config_bulk_set_ggtt_locked() - Provision many VFs with GGTT.
>   * @gt: the &xe_gt (can't be media)
>   * @vfid: starting VF identifier (can't be 0)
>   * @num_vfs: number of VFs to provision
> @@ -678,31 +678,49 @@ static int pf_config_bulk_set_u64_done(struct xe_gt *gt, unsigned int first, uns
>   *
>   * Return: 0 on success or a negative error code on failure.
>   */
> -int xe_gt_sriov_pf_config_bulk_set_ggtt(struct xe_gt *gt, unsigned int vfid,
> -					unsigned int num_vfs, u64 size)
> +int xe_gt_sriov_pf_config_bulk_set_ggtt_locked(struct xe_gt *gt, unsigned int vfid,
> +					       unsigned int num_vfs, u64 size)
>  {
>  	unsigned int n;
>  	int err = 0;
>  
>  	xe_gt_assert(gt, vfid);
>  	xe_gt_assert(gt, xe_gt_is_main_type(gt));
> +	lockdep_assert_held(xe_gt_sriov_pf_master_mutex(gt));
>  
>  	if (!num_vfs)
>  		return 0;
>  
> -	mutex_lock(xe_gt_sriov_pf_master_mutex(gt));
>  	for (n = vfid; n < vfid + num_vfs; n++) {
>  		err = pf_provision_vf_ggtt(gt, n, size);
>  		if (err)
>  			break;
>  	}
> -	mutex_unlock(xe_gt_sriov_pf_master_mutex(gt));
>  
>  	return pf_config_bulk_set_u64_done(gt, vfid, num_vfs, size,
> -					   xe_gt_sriov_pf_config_get_ggtt,
> +					   pf_get_vf_config_ggtt,
>  					   "GGTT", n, err);
>  }
>  
> +/**
> + * xe_gt_sriov_pf_config_bulk_set_ggtt() - Provision many VFs with GGTT.
> + * @gt: the &xe_gt (can't be media)
> + * @vfid: starting VF identifier (can't be 0)
> + * @num_vfs: number of VFs to provision
> + * @size: requested GGTT size
> + *
> + * This function can only be called on PF.
> + *
> + * Return: 0 on success or a negative error code on failure.
> + */
> +int xe_gt_sriov_pf_config_bulk_set_ggtt(struct xe_gt *gt, unsigned int vfid,
> +					unsigned int num_vfs, u64 size)
> +{
> +	guard(mutex)(xe_gt_sriov_pf_master_mutex(gt));
> +
> +	return xe_gt_sriov_pf_config_bulk_set_ggtt_locked(gt, vfid, num_vfs, size);
> +}
> +
>  /* Return: size of the largest continuous GGTT region */
>  static u64 pf_get_max_ggtt(struct xe_gt *gt)
>  {
> @@ -775,10 +793,9 @@ int xe_gt_sriov_pf_config_set_fair_ggtt(struct xe_gt *gt, unsigned int vfid,
>  	xe_gt_assert(gt, num_vfs);
>  	xe_gt_assert(gt, xe_gt_is_main_type(gt));
>  
> -	mutex_lock(xe_gt_sriov_pf_master_mutex(gt));
> +	guard(mutex)(xe_gt_sriov_pf_master_mutex(gt));
> +
>  	fair = pf_estimate_fair_ggtt(gt, num_vfs);
> -	mutex_unlock(xe_gt_sriov_pf_master_mutex(gt));
> -
>  	if (!fair)
>  		return -ENOSPC;
>  
> @@ -787,7 +804,7 @@ int xe_gt_sriov_pf_config_set_fair_ggtt(struct xe_gt *gt, unsigned int vfid,
>  		xe_gt_sriov_info(gt, "Using non-profile provisioning (%s %llu vs %llu)\n",
>  				 "GGTT", fair, profile);
>  
> -	return xe_gt_sriov_pf_config_bulk_set_ggtt(gt, vfid, num_vfs, fair);
> +	return xe_gt_sriov_pf_config_bulk_set_ggtt_locked(gt, vfid, num_vfs, fair);
>  }
>  
>  /**
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h
> index 2ec62c12ad5c..3741202908ee 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.h
> @@ -18,6 +18,8 @@ int xe_gt_sriov_pf_config_set_fair_ggtt(struct xe_gt *gt,
>  					unsigned int vfid, unsigned int num_vfs);
>  int xe_gt_sriov_pf_config_bulk_set_ggtt(struct xe_gt *gt,
>  					unsigned int vfid, unsigned int num_vfs, u64 size);
> +int xe_gt_sriov_pf_config_bulk_set_ggtt_locked(struct xe_gt *gt,
> +					       unsigned int vfid, unsigned int num_vfs, u64 size);
>  
>  u32 xe_gt_sriov_pf_config_get_ctxs(struct xe_gt *gt, unsigned int vfid);
>  int xe_gt_sriov_pf_config_set_ctxs(struct xe_gt *gt, unsigned int vfid, u32 num_ctxs);
> -- 
> 2.47.1
> 

Reviewed-by: Piotr Piórkowski <[email protected]>

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