diff options
Diffstat (limited to 'drivers/gpu/drm/drm_gem.c')
-rw-r--r-- | drivers/gpu/drm/drm_gem.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index ad124f5a6f4d..388b3742e562 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1233,3 +1233,81 @@ void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr) obj->dev->driver->gem_prime_vunmap(obj, vaddr); } EXPORT_SYMBOL(drm_gem_vunmap); + +/** + * drm_gem_lock_reservations - Sets up the ww context and acquires + * the lock on an array of GEM objects. + * + * Once you've locked your reservations, you'll want to set up space + * for your shared fences (if applicable), submit your job, then + * drm_gem_unlock_reservations(). + * + * @objs: drm_gem_objects to lock + * @count: Number of objects in @objs + * @acquire_ctx: struct ww_acquire_ctx that will be initialized as + * part of tracking this set of locked reservations. + */ +int +drm_gem_lock_reservations(struct drm_gem_object **objs, int count, + struct ww_acquire_ctx *acquire_ctx) +{ + int contended = -1; + int i, ret; + + ww_acquire_init(acquire_ctx, &reservation_ww_class); + +retry: + if (contended != -1) { + struct drm_gem_object *obj = objs[contended]; + + ret = ww_mutex_lock_slow_interruptible(&obj->resv->lock, + acquire_ctx); + if (ret) { + ww_acquire_done(acquire_ctx); + return ret; + } + } + + for (i = 0; i < count; i++) { + if (i == contended) + continue; + + ret = ww_mutex_lock_interruptible(&objs[i]->resv->lock, + acquire_ctx); + if (ret) { + int j; + + for (j = 0; j < i; j++) + ww_mutex_unlock(&objs[j]->resv->lock); + + if (contended != -1 && contended >= i) + ww_mutex_unlock(&objs[contended]->resv->lock); + + if (ret == -EDEADLK) { + contended = i; + goto retry; + } + + ww_acquire_done(acquire_ctx); + return ret; + } + } + + ww_acquire_done(acquire_ctx); + + return 0; +} +EXPORT_SYMBOL(drm_gem_lock_reservations); + +void +drm_gem_unlock_reservations(struct drm_gem_object **objs, int count, + struct ww_acquire_ctx *acquire_ctx) +{ + int i; + + for (i = 0; i < count; i++) + ww_mutex_unlock(&objs[i]->resv->lock); + + ww_acquire_fini(acquire_ctx); +} +EXPORT_SYMBOL(drm_gem_unlock_reservations); |