0,0 → 1,126 |
/* |
* Copyright (C) 2014 Red Hat |
* Author: Rob Clark <robdclark@gmail.com> |
* |
* Permission is hereby granted, free of charge, to any person obtaining a |
* copy of this software and associated documentation files (the "Software"), |
* to deal in the Software without restriction, including without limitation |
* the rights to use, copy, modify, merge, publish, distribute, sublicense, |
* and/or sell copies of the Software, and to permit persons to whom the |
* Software is furnished to do so, subject to the following conditions: |
* |
* The above copyright notice and this permission notice shall be included in |
* all copies or substantial portions of the Software. |
* |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR |
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
* OTHER DEALINGS IN THE SOFTWARE. |
*/ |
|
#ifndef DRM_MODESET_LOCK_H_ |
#define DRM_MODESET_LOCK_H_ |
|
#include <linux/ww_mutex.h> |
|
struct drm_modeset_lock; |
|
/** |
* drm_modeset_acquire_ctx - locking context (see ww_acquire_ctx) |
* @ww_ctx: base acquire ctx |
* @contended: used internally for -EDEADLK handling |
* @locked: list of held locks |
* |
* Each thread competing for a set of locks must use one acquire |
* ctx. And if any lock fxn returns -EDEADLK, it must backoff and |
* retry. |
*/ |
struct drm_modeset_acquire_ctx { |
|
struct ww_acquire_ctx ww_ctx; |
|
/** |
* Contended lock: if a lock is contended you should only call |
* drm_modeset_backoff() which drops locks and slow-locks the |
* contended lock. |
*/ |
struct drm_modeset_lock *contended; |
|
/** |
* list of held locks (drm_modeset_lock) |
*/ |
struct list_head locked; |
}; |
|
/** |
* drm_modeset_lock - used for locking modeset resources. |
* @mutex: resource locking |
* @head: used to hold it's place on state->locked list when |
* part of an atomic update |
* |
* Used for locking CRTCs and other modeset resources. |
*/ |
struct drm_modeset_lock { |
/** |
* modeset lock |
*/ |
struct ww_mutex mutex; |
|
/** |
* Resources that are locked as part of an atomic update are added |
* to a list (so we know what to unlock at the end). |
*/ |
struct list_head head; |
}; |
|
extern struct ww_class crtc_ww_class; |
|
void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, |
uint32_t flags); |
void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx); |
void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx); |
void drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx); |
int drm_modeset_backoff_interruptible(struct drm_modeset_acquire_ctx *ctx); |
|
/** |
* drm_modeset_lock_init - initialize lock |
* @lock: lock to init |
*/ |
static inline void drm_modeset_lock_init(struct drm_modeset_lock *lock) |
{ |
ww_mutex_init(&lock->mutex, &crtc_ww_class); |
INIT_LIST_HEAD(&lock->head); |
} |
|
/** |
* drm_modeset_lock_fini - cleanup lock |
* @lock: lock to cleanup |
*/ |
static inline void drm_modeset_lock_fini(struct drm_modeset_lock *lock) |
{ |
WARN_ON(!list_empty(&lock->head)); |
} |
|
/** |
* drm_modeset_is_locked - equivalent to mutex_is_locked() |
* @lock: lock to check |
*/ |
static inline bool drm_modeset_is_locked(struct drm_modeset_lock *lock) |
{ |
return ww_mutex_is_locked(&lock->mutex); |
} |
|
int drm_modeset_lock(struct drm_modeset_lock *lock, |
struct drm_modeset_acquire_ctx *ctx); |
int drm_modeset_lock_interruptible(struct drm_modeset_lock *lock, |
struct drm_modeset_acquire_ctx *ctx); |
void drm_modeset_unlock(struct drm_modeset_lock *lock); |
|
struct drm_device; |
int drm_modeset_lock_all_crtcs(struct drm_device *dev, |
struct drm_modeset_acquire_ctx *ctx); |
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#endif /* DRM_MODESET_LOCK_H_ */ |