1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */ 2 3 #ifndef __DRM_EXEC_H__ 4 #define __DRM_EXEC_H__ 5 6 #include <linux/compiler.h> 7 #include <linux/ww_mutex.h> 8 9 #define DRM_EXEC_INTERRUPTIBLE_WAIT BIT(0) 10 #define DRM_EXEC_IGNORE_DUPLICATES BIT(1) 11 12 struct drm_gem_object; 13 14 /** 15 * struct drm_exec - Execution context 16 */ 17 struct drm_exec { 18 /** 19 * @flags: Flags to control locking behavior 20 */ 21 uint32_t flags; 22 23 /** 24 * @ticket: WW ticket used for acquiring locks 25 */ 26 struct ww_acquire_ctx ticket; 27 28 /** 29 * @num_objects: number of objects locked 30 */ 31 unsigned int num_objects; 32 33 /** 34 * @max_objects: maximum objects in array 35 */ 36 unsigned int max_objects; 37 38 /** 39 * @objects: array of the locked objects 40 */ 41 struct drm_gem_object **objects; 42 43 /** 44 * @contended: contended GEM object we backed off for 45 */ 46 struct drm_gem_object *contended; 47 48 /** 49 * @prelocked: already locked GEM object due to contention 50 */ 51 struct drm_gem_object *prelocked; 52 }; 53 54 /** 55 * drm_exec_for_each_locked_object - iterate over all the locked objects 56 * @exec: drm_exec object 57 * @index: unsigned long index for the iteration 58 * @obj: the current GEM object 59 * 60 * Iterate over all the locked GEM objects inside the drm_exec object. 61 */ 62 #define drm_exec_for_each_locked_object(exec, index, obj) \ 63 for (index = 0, obj = (exec)->objects[0]; \ 64 index < (exec)->num_objects; \ 65 ++index, obj = (exec)->objects[index]) 66 67 /** 68 * drm_exec_until_all_locked - loop until all GEM objects are locked 69 * @exec: drm_exec object 70 * 71 * Core functionality of the drm_exec object. Loops until all GEM objects are 72 * locked and no more contention exists. At the beginning of the loop it is 73 * guaranteed that no GEM object is locked. 74 * 75 * Since labels can't be defined local to the loops body we use a jump pointer 76 * to make sure that the retry is only used from within the loops body. 77 */ 78 #define drm_exec_until_all_locked(exec) \ 79 __PASTE(__drm_exec_, __LINE__): \ 80 for (void *__drm_exec_retry_ptr; ({ \ 81 __drm_exec_retry_ptr = &&__PASTE(__drm_exec_, __LINE__);\ 82 (void)__drm_exec_retry_ptr; \ 83 drm_exec_cleanup(exec); \ 84 });) 85 86 /** 87 * drm_exec_retry_on_contention - restart the loop to grap all locks 88 * @exec: drm_exec object 89 * 90 * Control flow helper to continue when a contention was detected and we need to 91 * clean up and re-start the loop to prepare all GEM objects. 92 */ 93 #define drm_exec_retry_on_contention(exec) \ 94 do { \ 95 if (unlikely(drm_exec_is_contended(exec))) \ 96 goto *__drm_exec_retry_ptr; \ 97 } while (0) 98 99 /** 100 * drm_exec_is_contended - check for contention 101 * @exec: drm_exec object 102 * 103 * Returns true if the drm_exec object has run into some contention while 104 * locking a GEM object and needs to clean up. 105 */ 106 static inline bool drm_exec_is_contended(struct drm_exec *exec) 107 { 108 return !!exec->contended; 109 } 110 111 void drm_exec_init(struct drm_exec *exec, uint32_t flags); 112 void drm_exec_fini(struct drm_exec *exec); 113 bool drm_exec_cleanup(struct drm_exec *exec); 114 int drm_exec_lock_obj(struct drm_exec *exec, struct drm_gem_object *obj); 115 void drm_exec_unlock_obj(struct drm_exec *exec, struct drm_gem_object *obj); 116 int drm_exec_prepare_obj(struct drm_exec *exec, struct drm_gem_object *obj, 117 unsigned int num_fences); 118 int drm_exec_prepare_array(struct drm_exec *exec, 119 struct drm_gem_object **objects, 120 unsigned int num_objects, 121 unsigned int num_fences); 122 123 #endif 124