[PATCH 2/4] drm/ttm: add a debugfs file for the global page pools

[Daniel Vetter]

On Tue, Jan 19, 2021 at 01:18:19PM +0100, Christian König wrote:
> Instead of printing this on the per device pool.
> 
> Signed-off-by: Christian König <christian.koenig at amd.com>

Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>

btw I think ttm should also set up the per-bdev debugfs stuff, feels silly
having that boilerplate. Same for the per-ttm_manager thing we have I
think.
-Daniel

> ---
>  drivers/gpu/drm/ttm/ttm_pool.c | 70 ++++++++++++++++++++++++----------
>  1 file changed, 50 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c
> index 7b2f60616750..1d61e8fc0e81 100644
> --- a/drivers/gpu/drm/ttm/ttm_pool.c
> +++ b/drivers/gpu/drm/ttm/ttm_pool.c
> @@ -42,6 +42,8 @@
>  #include <drm/ttm/ttm_bo_driver.h>
>  #include <drm/ttm/ttm_tt.h>
>  
> +#include "ttm_module.h"
> +
>  /**
>   * struct ttm_pool_dma - Helper object for coherent DMA mappings
>   *
> @@ -543,6 +545,17 @@ static unsigned int ttm_pool_type_count(struct ttm_pool_type *pt)
>  	return count;
>  }
>  
> +/* Print a nice header for the order */
> +static void ttm_pool_debugfs_header(struct seq_file *m)
> +{
> +	unsigned int i;
> +
> +	seq_puts(m, "\t ");
> +	for (i = 0; i < MAX_ORDER; ++i)
> +		seq_printf(m, " ---%2u---", i);
> +	seq_puts(m, "\n");
> +}
> +
>  /* Dump information about the different pool types */
>  static void ttm_pool_debugfs_orders(struct ttm_pool_type *pt,
>  				    struct seq_file *m)
> @@ -554,6 +567,35 @@ static void ttm_pool_debugfs_orders(struct ttm_pool_type *pt,
>  	seq_puts(m, "\n");
>  }
>  
> +/* Dump the total amount of allocated pages */
> +static void ttm_pool_debugfs_footer(struct seq_file *m)
> +{
> +	seq_printf(m, "\ntotal\t: %8lu of %8lu\n",
> +		   atomic_long_read(&allocated_pages), page_pool_size);
> +}
> +
> +/* Dump the information for the global pools */
> +static int ttm_pool_debugfs_globals_show(struct seq_file *m, void *data)
> +{
> +	ttm_pool_debugfs_header(m);
> +
> +	spin_lock(&shrinker_lock);
> +	seq_puts(m, "wc\t:");
> +	ttm_pool_debugfs_orders(global_write_combined, m);
> +	seq_puts(m, "uc\t:");
> +	ttm_pool_debugfs_orders(global_uncached, m);
> +	seq_puts(m, "wc 32\t:");
> +	ttm_pool_debugfs_orders(global_dma32_write_combined, m);
> +	seq_puts(m, "uc 32\t:");
> +	ttm_pool_debugfs_orders(global_dma32_uncached, m);
> +	spin_unlock(&shrinker_lock);
> +
> +	ttm_pool_debugfs_footer(m);
> +
> +	return 0;
> +}
> +DEFINE_SHOW_ATTRIBUTE(ttm_pool_debugfs_globals);
> +
>  /**
>   * ttm_pool_debugfs - Debugfs dump function for a pool
>   *
> @@ -566,23 +608,9 @@ int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m)
>  {
>  	unsigned int i;
>  
> -	spin_lock(&shrinker_lock);
> -
> -	seq_puts(m, "\t ");
> -	for (i = 0; i < MAX_ORDER; ++i)
> -		seq_printf(m, " ---%2u---", i);
> -	seq_puts(m, "\n");
> -
> -	seq_puts(m, "wc\t:");
> -	ttm_pool_debugfs_orders(global_write_combined, m);
> -	seq_puts(m, "uc\t:");
> -	ttm_pool_debugfs_orders(global_uncached, m);
> -
> -	seq_puts(m, "wc 32\t:");
> -	ttm_pool_debugfs_orders(global_dma32_write_combined, m);
> -	seq_puts(m, "uc 32\t:");
> -	ttm_pool_debugfs_orders(global_dma32_uncached, m);
> +	ttm_pool_debugfs_header(m);
>  
> +	spin_lock(&shrinker_lock);
>  	for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) {
>  		seq_puts(m, "DMA ");
>  		switch (i) {
> @@ -598,12 +626,9 @@ int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m)
>  		}
>  		ttm_pool_debugfs_orders(pool->caching[i].orders, m);
>  	}
> -
> -	seq_printf(m, "\ntotal\t: %8lu of %8lu\n",
> -		   atomic_long_read(&allocated_pages), page_pool_size);
> -
>  	spin_unlock(&shrinker_lock);
>  
> +	ttm_pool_debugfs_footer(m);
>  	return 0;
>  }
>  EXPORT_SYMBOL(ttm_pool_debugfs);
> @@ -660,6 +685,11 @@ int ttm_pool_mgr_init(unsigned long num_pages)
>  				   ttm_uncached, i);
>  	}
>  
> +#ifdef CONFIG_DEBUG_FS
> +	debugfs_create_file("page_pool", 0444, ttm_debugfs_root, NULL,
> +			    &ttm_pool_debugfs_globals_fops);
> +#endif
> +
>  	mm_shrinker.count_objects = ttm_pool_shrinker_count;
>  	mm_shrinker.scan_objects = ttm_pool_shrinker_scan;
>  	mm_shrinker.seeks = 1;
> -- 
> 2.25.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch