diff options
Diffstat (limited to 'drivers/connector/cn_proc.c')
| -rw-r--r-- | drivers/connector/cn_proc.c | 21 | 
1 files changed, 14 insertions, 7 deletions
diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c index d58ce664da84..646ad385e490 100644 --- a/drivers/connector/cn_proc.c +++ b/drivers/connector/cn_proc.c @@ -18,6 +18,7 @@  #include <linux/pid_namespace.h>  #include <linux/cn_proc.h> +#include <linux/local_lock.h>  /*   * Size of a cn_msg followed by a proc_event structure.  Since the @@ -38,25 +39,31 @@ static inline struct cn_msg *buffer_to_cn_msg(__u8 *buffer)  static atomic_t proc_event_num_listeners = ATOMIC_INIT(0);  static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC }; -/* proc_event_counts is used as the sequence number of the netlink message */ -static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 }; +/* local_event.count is used as the sequence number of the netlink message */ +struct local_event { +	local_lock_t lock; +	__u32 count; +}; +static DEFINE_PER_CPU(struct local_event, local_event) = { +	.lock = INIT_LOCAL_LOCK(lock), +};  static inline void send_msg(struct cn_msg *msg)  { -	preempt_disable(); +	local_lock(&local_event.lock); -	msg->seq = __this_cpu_inc_return(proc_event_counts) - 1; +	msg->seq = __this_cpu_inc_return(local_event.count) - 1;  	((struct proc_event *)msg->data)->cpu = smp_processor_id();  	/* -	 * Preemption remains disabled during send to ensure the messages are -	 * ordered according to their sequence numbers. +	 * local_lock() disables preemption during send to ensure the messages +	 * are ordered according to their sequence numbers.  	 *  	 * If cn_netlink_send() fails, the data is not sent.  	 */  	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT); -	preempt_enable(); +	local_unlock(&local_event.lock);  }  void proc_fork_connector(struct task_struct *task)  | 
