From 22b929b25293208d9d34ff6fa783c6788e0b791c Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Tue, 3 Jun 2025 12:27:50 +0100 Subject: [PATCH] drm/ttm: Increase pool shrinker batch target MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: Tvrtko Ursulin Cc: Christian König Cc: Thomas Hellström Reviewed-by: Christian König Signed-off-by: Tvrtko Ursulin Link: https://lore.kernel.org/r/20250603112750.34997-3-tvrtko.ursulin@igalia.com --- drivers/gpu/drm/ttm/ttm_pool.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c index cb44745106bc4..90b1bb903b930 100644 --- a/drivers/gpu/drm/ttm/ttm_pool.c +++ b/drivers/gpu/drm/ttm/ttm_pool.c @@ -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); -- 2.47.2