diff options
| author | Satyanarayana K V P <satyanarayana.k.v.p@intel.com> | 2026-02-20 08:55:21 +0300 |
|---|---|---|
| committer | Matthew Brost <matthew.brost@intel.com> | 2026-02-20 21:54:02 +0300 |
| commit | 16843e6638b743dd0376a1fc0845f2fd34daff98 (patch) | |
| tree | 309f769d868398532378b12c4929e9ed1256d5be /include | |
| parent | a5d5634cde48a9fcd68c8504aa07f89f175074a0 (diff) | |
| download | linux-16843e6638b743dd0376a1fc0845f2fd34daff98.tar.xz | |
drm/sa: Split drm_suballoc_new() into SA alloc and init helpers
drm_suballoc_new() currently both allocates the SA object using kmalloc()
and searches for a suitable hole in the sub-allocator for the requested
size. If SA allocation is done by holding sub-allocator mutex, this design
can lead to reclaim safety issues.
By splitting the kmalloc() step outside of the critical section, we allow
the memory allocation to use GFP_KERNEL (reclaim-safe) while ensuring that
the initialization step that holds reclaim-tainted locks (sub-allocator
mutex) operates in a reclaim-unsafe context with pre-allocated memory.
This separation prevents potential deadlocks where memory reclaim could
attempt to acquire locks that are already held during the sub-allocator
operations.
Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: dri-devel@lists.freedesktop.org
Cc: Maarten Lankhorst <dev@lankhorst.se>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Maarten Lankhorst <dev@lankhorst.se>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260220055519.2485681-6-satyanarayana.k.v.p@intel.com
Diffstat (limited to 'include')
| -rw-r--r-- | include/drm/drm_suballoc.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/drm/drm_suballoc.h b/include/drm/drm_suballoc.h index 7ba72a81a808..29befdda35d2 100644 --- a/include/drm/drm_suballoc.h +++ b/include/drm/drm_suballoc.h @@ -53,6 +53,12 @@ void drm_suballoc_manager_init(struct drm_suballoc_manager *sa_manager, void drm_suballoc_manager_fini(struct drm_suballoc_manager *sa_manager); +struct drm_suballoc *drm_suballoc_alloc(gfp_t gfp); + +int drm_suballoc_insert(struct drm_suballoc_manager *sa_manager, + struct drm_suballoc *sa, size_t size, bool intr, + size_t align); + struct drm_suballoc * drm_suballoc_new(struct drm_suballoc_manager *sa_manager, size_t size, gfp_t gfp, bool intr, size_t align); |