On Fri, Dec 18, 2020 at 06:55:37PM +0100, Christian König wrote:
Useful for testing.
Signed-off-by: Christian König christian.koenig@amd.com
drivers/gpu/drm/ttm/ttm_pool.c | 50 ++++++++++++++++++++++------------ 1 file changed, 32 insertions(+), 18 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c index 1d61e8fc0e81..1cdacd58753a 100644 --- a/drivers/gpu/drm/ttm/ttm_pool.c +++ b/drivers/gpu/drm/ttm/ttm_pool.c @@ -529,6 +529,28 @@ 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 +655,19 @@ 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_KERNEL };
- do
num_freed += ttm_pool_shrink();- while (!num_freed && atomic_long_read(&allocated_pages));
Need to wrap this in fs_reclaim_acquire/release(), otherwise lockdep won't connect the dots and the dedicated testing interface here isn't very useful.
Also this is a bit a confusing interface, I'd expect the show function to do the counting, and then the write function would try to write shrink as many objects as requests with the _scan function.
Both should be annotated with fs_reclaim_acquire/release.
- seq_printf(m, "%lu/%lu\n", ttm_pool_shrinker_count(&mm_shrinker, &sc),
ttm_pool_shrinker_scan(&mm_shrinker, &sc));
- 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 +700,8 @@ 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);
I think an interface per pool would make more sense for dedicated testing. I'm kinda wondering whether we shouldn't do this in mm/ for all shrinkers by default, it's really quite neat for being able to test stuff. -Daniel
#endif
mm_shrinker.count_objects = ttm_pool_shrinker_count;
2.25.1