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 <tvrtko.ursu...@igalia.com>
Cc: Christian König <christian.koe...@amd.com>
Cc: Thomas Hellström <thomas.hellst...@linux.intel.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 c060c90b89c0..e671812789ea 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);
--
2.48.0
