Commit 22b929b2 authored by Tvrtko Ursulin's avatar Tvrtko Ursulin Committed by Tvrtko Ursulin
Browse files

drm/ttm: Increase pool shrinker batch target 



The default core shrink target of 128 pages (SHRINK_BATCH) is quite low
relative to how cheap TTM pool shrinking is, and how the free pages are
distributed in page order pools.

We can make the target a bit more aggressive by making it roughly the
average number of pages across all pools, freeing more of the cached
pages every time shrinker core invokes our callback.

Signed-off-by: default avatarTvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarTvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20250603112750.34997-3-tvrtko.ursulin@igalia.com
parent eac21f8e

drivers/gpu/drm/ttm/ttm_pool.c

+8 −1
Original line number Diff line number Diff line
@@ -1265,10 +1265,16 @@ int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m) 
}

EXPORT_SYMBOL(ttm_pool_debugfs);



/* Free average pool number of pages.  */

#define TTM_SHRINKER_BATCH ((1 << (MAX_PAGE_ORDER / 2)) * NR_PAGE_ORDERS)



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

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

{

	struct shrink_control sc = { .gfp_mask = GFP_NOFS };

	struct shrink_control sc = {

		.gfp_mask = GFP_NOFS,

		.nr_to_scan = TTM_SHRINKER_BATCH,

	};



	fs_reclaim_acquire(GFP_KERNEL);

	seq_printf(m, "%lu/%lu\n", ttm_pool_shrinker_count(mm_shrinker, &sc),
@@ -1326,6 +1332,7 @@ int ttm_pool_mgr_init(unsigned long num_pages) 


	mm_shrinker->count_objects = ttm_pool_shrinker_count;

	mm_shrinker->scan_objects = ttm_pool_shrinker_scan;

	mm_shrinker->batch = TTM_SHRINKER_BATCH;

	mm_shrinker->seeks = 1;



	shrinker_register(mm_shrinker);