Commit 56851768 authored by Christian König's avatar Christian König
Browse files

drm/ttm: add debugfs entry to test pool shrinker v2 



Useful for testing.

v2: add fs_reclaim_acquire()/_release()

Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/414955/
parent ba051901

drivers/gpu/drm/ttm/ttm_pool.c

+35 −18
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 


#include <linux/module.h>

#include <linux/dma-mapping.h>

#include <linux/sched/mm.h>



#ifdef CONFIG_X86

#include <asm/set_memory.h>
@@ -529,6 +530,28 @@ void ttm_pool_fini(struct ttm_pool *pool) 
}

EXPORT_SYMBOL(ttm_pool_fini);



/* As long as pages are available make sure to release at least one */

static unsigned long ttm_pool_shrinker_scan(struct shrinker *shrink,

					    struct shrink_control *sc)

{

	unsigned long num_freed = 0;



	do

		num_freed += ttm_pool_shrink();

	while (!num_freed && atomic_long_read(&allocated_pages));



	return num_freed;

}



/* Return the number of pages available or SHRINK_EMPTY if we have none */

static unsigned long ttm_pool_shrinker_count(struct shrinker *shrink,

					     struct shrink_control *sc)

{

	unsigned long num_pages = atomic_long_read(&allocated_pages);



	return num_pages ? num_pages : SHRINK_EMPTY;

}



#ifdef CONFIG_DEBUG_FS

/* Count the number of pages available in a pool_type */

static unsigned int ttm_pool_type_count(struct ttm_pool_type *pt)
@@ -633,29 +656,21 @@ int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m) 
}

EXPORT_SYMBOL(ttm_pool_debugfs);



#endif



/* As long as pages are available make sure to release at least one */

static unsigned long ttm_pool_shrinker_scan(struct shrinker *shrink,

					    struct shrink_control *sc)

/* Test the shrinker functions and dump the result */

static int ttm_pool_debugfs_shrink_show(struct seq_file *m, void *data)

{

	unsigned long num_freed = 0;

	struct shrink_control sc = { .gfp_mask = GFP_NOFS };



	do

		num_freed += ttm_pool_shrink();

	while (!num_freed && atomic_long_read(&allocated_pages));

	fs_reclaim_acquire(GFP_KERNEL);

	seq_printf(m, "%lu/%lu\n", ttm_pool_shrinker_count(&mm_shrinker, &sc),

		   ttm_pool_shrinker_scan(&mm_shrinker, &sc));

	fs_reclaim_release(GFP_KERNEL);



	return num_freed;

	return 0;

}

DEFINE_SHOW_ATTRIBUTE(ttm_pool_debugfs_shrink);



/* Return the number of pages available or SHRINK_EMPTY if we have none */

static unsigned long ttm_pool_shrinker_count(struct shrinker *shrink,

					     struct shrink_control *sc)

{

	unsigned long num_pages = atomic_long_read(&allocated_pages);



	return num_pages ? num_pages : SHRINK_EMPTY;

}

#endif



/**

 * ttm_pool_mgr_init - Initialize globals
@@ -688,6 +703,8 @@ int ttm_pool_mgr_init(unsigned long num_pages) 
#ifdef CONFIG_DEBUG_FS

	debugfs_create_file("page_pool", 0444, ttm_debugfs_root, NULL,

			    &ttm_pool_debugfs_globals_fops);

	debugfs_create_file("page_pool_shrink", 0400, ttm_debugfs_root, NULL,

			    &ttm_pool_debugfs_shrink_fops);

#endif



	mm_shrinker.count_objects = ttm_pool_shrinker_count;