diff options
Diffstat (limited to 'drivers/gpu/drm/drm_modeset_lock.c')
| -rw-r--r-- | drivers/gpu/drm/drm_modeset_lock.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c index 61146f5b4f56..bf60f2645e55 100644 --- a/drivers/gpu/drm/drm_modeset_lock.c +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -33,7 +33,7 @@ * to use &ww_mutex and acquire-contexts to avoid deadlocks. But because * the locking is more distributed around the driver code, we want a bit * of extra utility/tracking out of our acquire-ctx. This is provided - * by drm_modeset_lock / drm_modeset_acquire_ctx. + * by &struct drm_modeset_lock and &struct drm_modeset_acquire_ctx. * * For basic principles of &ww_mutex, see: Documentation/locking/ww-mutex-design.txt * @@ -52,14 +52,16 @@ * drm_modeset_drop_locks(&ctx); * drm_modeset_acquire_fini(&ctx); * - * On top of of these per-object locks using &ww_mutex there's also an overall - * dev->mode_config.lock, for protecting everything else. Mostly this means - * probe state of connectors, and preventing hotplug add/removal of connectors. + * On top of of these per-object locks using &ww_mutex there's also an overall + * &drm_mode_config.mutex, for protecting everything else. Mostly this means + * probe state of connectors, and preventing hotplug add/removal of connectors. * - * Finally there's a bunch of dedicated locks to protect drm core internal - * lists and lookup data structures. + * Finally there's a bunch of dedicated locks to protect drm core internal + * lists and lookup data structures. */ +static DEFINE_WW_CLASS(crtc_ww_class); + /** * drm_modeset_lock_all - take all modeset locks * @dev: DRM device @@ -69,7 +71,7 @@ * drm_modeset_unlock_all() function. * * This function is deprecated. It allocates a lock acquisition context and - * stores it in the DRM device's ->mode_config. This facilitate conversion of + * stores it in &drm_device.mode_config. This facilitate conversion of * existing code because it removes the need to manually deal with the * acquisition context, but it is also brittle because the context is global * and care must be taken not to nest calls. New code should use the @@ -122,7 +124,7 @@ EXPORT_SYMBOL(drm_modeset_lock_all); * drm_modeset_lock_all() function. * * This function is deprecated. It uses the lock acquisition context stored - * in the DRM device's ->mode_config. This facilitates conversion of existing + * in &drm_device.mode_config. This facilitates conversion of existing * code because it removes the need to manually deal with the acquisition * context, but it is also brittle because the context is global and care must * be taken not to nest calls. New code should pass the acquisition context @@ -398,6 +400,17 @@ int drm_modeset_backoff_interruptible(struct drm_modeset_acquire_ctx *ctx) EXPORT_SYMBOL(drm_modeset_backoff_interruptible); /** + * drm_modeset_lock_init - initialize lock + * @lock: lock to init + */ +void drm_modeset_lock_init(struct drm_modeset_lock *lock) +{ + ww_mutex_init(&lock->mutex, &crtc_ww_class); + INIT_LIST_HEAD(&lock->head); +} +EXPORT_SYMBOL(drm_modeset_lock_init); + +/** * drm_modeset_lock - take modeset lock * @lock: lock to take * @ctx: acquire ctx @@ -455,7 +468,7 @@ EXPORT_SYMBOL(drm_modeset_unlock); * This function takes all modeset locks, suitable where a more fine-grained * scheme isn't (yet) implemented. * - * Unlike drm_modeset_lock_all(), it doesn't take the dev->mode_config.mutex + * Unlike drm_modeset_lock_all(), it doesn't take the &drm_mode_config.mutex * since that lock isn't required for modeset state changes. Callers which * need to grab that lock too need to do so outside of the acquire context * @ctx. |