Re: [PATCH 1/2] drm/ttm: Check ttm_debugfs_root before creating files under it

[Christian König]

Am 13.01.23 um 06:34 schrieb Ma Jun:

Check the ttm_debugfs_root before creating files under it.
If the ttm_debugfs_root is NULL, all the files created for
ttm/ will be placed in the /sys/kerne/debug/ but not
/sys/kernel/debug/ttm/

Well NAK for upstreaming. Why should ttm_debugfs_root be NULL here?

Regards,
Christian.

Signed-off-by: Ma Jun <jun....@amd.com>
---
  drivers/gpu/drm/ttm/ttm_device.c |  3 ++-
  drivers/gpu/drm/ttm/ttm_pool.c   | 10 ++++++----
  drivers/gpu/drm/ttm/ttm_tt.c     |  5 +++--
  3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_device.c b/drivers/gpu/drm/ttm/ttm_device.c
index e7147e304637..967bc2244df3 100644
--- a/drivers/gpu/drm/ttm/ttm_device.c
+++ b/drivers/gpu/drm/ttm/ttm_device.c
@@ -105,7 +105,8 @@ static int ttm_global_init(void)
        INIT_LIST_HEAD(&glob->device_list);
        atomic_set(&glob->bo_count, 0);

- debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,

+       if(ttm_debugfs_root)
+               debugfs_create_atomic_t("buffer_objects", 0444, 
ttm_debugfs_root,
                                &glob->bo_count);
  out:
        if (ret && ttm_debugfs_root)
diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c
index 21b61631f73a..d95a65f759df 100644
--- a/drivers/gpu/drm/ttm/ttm_pool.c
+++ b/drivers/gpu/drm/ttm/ttm_pool.c
@@ -713,10 +713,12 @@ 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);
+       if(ttm_debugfs_root) {
+               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;

diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index d505603930a7..fec443494ef0 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -394,8 +394,9 @@ DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
  void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
  {
  #ifdef CONFIG_DEBUG_FS
-       debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
-                           &ttm_tt_debugfs_shrink_fops);
+       if(ttm_debugfs_root)
+               debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
+                                   &ttm_tt_debugfs_shrink_fops);
  #endif

if (!ttm_pages_limit)