drm/rockchip: Convert psr_list_mutex to spinlock and use it

This patch converts the psr_list_mutex to a spinlock and locks
all access to psr_list to avoid races (however unlikely they
were).

Reviewed-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
This commit is contained in:
Sean Paul 2016-08-16 16:11:28 -07:00
parent 8f0ac5c483
commit 18d8d4d228
3 changed files with 20 additions and 9 deletions

View File

@ -157,7 +157,7 @@ static int rockchip_drm_bind(struct device *dev)
drm_dev->dev_private = private; drm_dev->dev_private = private;
INIT_LIST_HEAD(&private->psr_list); INIT_LIST_HEAD(&private->psr_list);
mutex_init(&private->psr_list_mutex); spin_lock_init(&private->psr_list_lock);
drm_mode_config_init(drm_dev); drm_mode_config_init(drm_dev);

View File

@ -63,7 +63,7 @@ struct rockchip_drm_private {
struct drm_atomic_state *state; struct drm_atomic_state *state;
struct list_head psr_list; struct list_head psr_list;
struct mutex psr_list_mutex; spinlock_t psr_list_lock;
}; };
int rockchip_register_crtc_funcs(struct drm_crtc *crtc, int rockchip_register_crtc_funcs(struct drm_crtc *crtc,

View File

@ -45,12 +45,18 @@ static struct psr_drv *find_psr_by_crtc(struct drm_crtc *crtc)
{ {
struct rockchip_drm_private *drm_drv = crtc->dev->dev_private; struct rockchip_drm_private *drm_drv = crtc->dev->dev_private;
struct psr_drv *psr; struct psr_drv *psr;
unsigned long flags;
list_for_each_entry(psr, &drm_drv->psr_list, list) spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
list_for_each_entry(psr, &drm_drv->psr_list, list) {
if (psr->encoder->crtc == crtc) if (psr->encoder->crtc == crtc)
return psr; goto out;
}
psr = ERR_PTR(-ENODEV);
return ERR_PTR(-ENODEV); out:
spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
return psr;
} }
static void psr_state_work(struct work_struct *work) static void psr_state_work(struct work_struct *work)
@ -173,7 +179,9 @@ void rockchip_drm_psr_flush(struct drm_device *dev)
{ {
struct rockchip_drm_private *drm_drv = dev->dev_private; struct rockchip_drm_private *drm_drv = dev->dev_private;
struct psr_drv *psr; struct psr_drv *psr;
unsigned long flags;
spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
list_for_each_entry(psr, &drm_drv->psr_list, list) { list_for_each_entry(psr, &drm_drv->psr_list, list) {
if (psr->request_state == PSR_DISABLE) if (psr->request_state == PSR_DISABLE)
continue; continue;
@ -183,6 +191,7 @@ void rockchip_drm_psr_flush(struct drm_device *dev)
psr_set_state(psr, PSR_FLUSH); psr_set_state(psr, PSR_FLUSH);
} }
spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
} }
EXPORT_SYMBOL(rockchip_drm_psr_flush); EXPORT_SYMBOL(rockchip_drm_psr_flush);
@ -199,6 +208,7 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder,
{ {
struct rockchip_drm_private *drm_drv = encoder->dev->dev_private; struct rockchip_drm_private *drm_drv = encoder->dev->dev_private;
struct psr_drv *psr; struct psr_drv *psr;
unsigned long flags;
if (!encoder || !psr_set) if (!encoder || !psr_set)
return -EINVAL; return -EINVAL;
@ -215,9 +225,9 @@ int rockchip_drm_psr_register(struct drm_encoder *encoder,
psr->encoder = encoder; psr->encoder = encoder;
psr->set = psr_set; psr->set = psr_set;
mutex_lock(&drm_drv->psr_list_mutex); spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
list_add_tail(&psr->list, &drm_drv->psr_list); list_add_tail(&psr->list, &drm_drv->psr_list);
mutex_unlock(&drm_drv->psr_list_mutex); spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
return 0; return 0;
} }
@ -235,8 +245,9 @@ void rockchip_drm_psr_unregister(struct drm_encoder *encoder)
{ {
struct rockchip_drm_private *drm_drv = encoder->dev->dev_private; struct rockchip_drm_private *drm_drv = encoder->dev->dev_private;
struct psr_drv *psr, *n; struct psr_drv *psr, *n;
unsigned long flags;
mutex_lock(&drm_drv->psr_list_mutex); spin_lock_irqsave(&drm_drv->psr_list_lock, flags);
list_for_each_entry_safe(psr, n, &drm_drv->psr_list, list) { list_for_each_entry_safe(psr, n, &drm_drv->psr_list, list) {
if (psr->encoder == encoder) { if (psr->encoder == encoder) {
del_timer(&psr->flush_timer); del_timer(&psr->flush_timer);
@ -244,6 +255,6 @@ void rockchip_drm_psr_unregister(struct drm_encoder *encoder)
kfree(psr); kfree(psr);
} }
} }
mutex_unlock(&drm_drv->psr_list_mutex); spin_unlock_irqrestore(&drm_drv->psr_list_lock, flags);
} }
EXPORT_SYMBOL(rockchip_drm_psr_unregister); EXPORT_SYMBOL(rockchip_drm_psr_unregister);