Re: [PATCH 07/13] drm/xe/sa: Allow making suballocations using custom gfp flags

[Matthew Brost <matthew.brost@intel.com>]

On Thu, Dec 12, 2024 at 02:01:35AM +0100, Michal Wajdeczko wrote:
> Actual xe_sa_manager implementation uses hardcoded GFP_KERNEL flag
> during creation of suballocations but in upcoming patch we want to
> reuse the xe_sa_manager in places where GFP_KERNEL is not allowed.
> Add another variant of the xe_sa_bo_new() function that accepts
> arbitrary gfp flags.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_sa.c | 15 ++++++++++++---
>  drivers/gpu/drm/xe/xe_sa.h | 10 ++++++++--
>  2 files changed, 20 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_sa.c b/drivers/gpu/drm/xe/xe_sa.c
> index 704332ef795f..d92d9836fa91 100644
> --- a/drivers/gpu/drm/xe/xe_sa.c
> +++ b/drivers/gpu/drm/xe/xe_sa.c
> @@ -78,8 +78,17 @@ struct xe_sa_manager *xe_sa_bo_manager_init(struct xe_tile *tile, u32 size, u32
>  	return sa_manager;
>  }
>  
> -struct drm_suballoc *xe_sa_bo_new(struct xe_sa_manager *sa_manager,
> -				  unsigned int size)
> +/**
> + * __xe_sa_bo_new() - Make a suballocation but use custom gfp flags.
> + * @sa_manager: the &xe_sa_manager
> + * @size: number of bytes we want to suballocate
> + * @gfp: gfp flags used for memory allocation. Typically GFP_KERNEL.
> + *
> + * Try to make a suballocation of size @size.
> + *
> + * Return: a &drm_suballoc, or an ERR_PTR.
> + */
> +struct drm_suballoc *__xe_sa_bo_new(struct xe_sa_manager *sa_manager, u32 size, gfp_t gfp)
>  {
>  	/*
>  	 * BB to large, return -ENOBUFS indicating user should split
> @@ -88,7 +97,7 @@ struct drm_suballoc *xe_sa_bo_new(struct xe_sa_manager *sa_manager,
>  	if (size > sa_manager->base.size)
>  		return ERR_PTR(-ENOBUFS);
>  
> -	return drm_suballoc_new(&sa_manager->base, size, GFP_KERNEL, true, 0);
> +	return drm_suballoc_new(&sa_manager->base, size, gfp, true, 0);
>  }
>  
>  void xe_sa_bo_flush_write(struct drm_suballoc *sa_bo)
> diff --git a/drivers/gpu/drm/xe/xe_sa.h b/drivers/gpu/drm/xe/xe_sa.h
> index 4e96483057d7..bf55d8c3b5eb 100644
> --- a/drivers/gpu/drm/xe/xe_sa.h
> +++ b/drivers/gpu/drm/xe/xe_sa.h
> @@ -5,6 +5,7 @@
>  #ifndef _XE_SA_H_
>  #define _XE_SA_H_
>  
> +#include <linux/types.h>
>  #include "xe_sa_types.h"
>  
>  struct dma_fence;
> @@ -13,8 +14,13 @@ struct xe_tile;
>  
>  struct xe_sa_manager *xe_sa_bo_manager_init(struct xe_tile *tile, u32 size, u32 align);
>  
> -struct drm_suballoc *xe_sa_bo_new(struct xe_sa_manager *sa_manager,
> -				  u32 size);
> +struct drm_suballoc *__xe_sa_bo_new(struct xe_sa_manager *sa_manager, u32 size, gfp_t gfp);
> +
> +static inline struct drm_suballoc *xe_sa_bo_new(struct xe_sa_manager *sa_manager, u32 size)

Nit: Kernel doc here.

With kernel doc:
Reviewed-by: Matthew Brost <matthew.brost@intel.com>

> +{
> +	return __xe_sa_bo_new(sa_manager, size, GFP_KERNEL);
> +}
> +
>  void xe_sa_bo_flush_write(struct drm_suballoc *sa_bo);
>  void xe_sa_bo_free(struct drm_suballoc *sa_bo,
>  		   struct dma_fence *fence);
> -- 
> 2.47.1
>