Re: [PATCH v3 2/6] sched/rtmutex/deadline: Fix a PI crash for deadline tasks
From: Xunlei Pang
Date: Wed Apr 20 2016 - 09:49:49 EST
On 2016/04/20 at 21:19, Peter Zijlstra wrote:
> On Thu, Apr 14, 2016 at 07:37:03PM +0800, Xunlei Pang wrote:
>> + /* Updated under pi_lock and rtmutex lock */
>> struct rb_node *pi_waiters_leftmost;
>> + struct rb_node *pi_waiters_leftmost_copy;
>> struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
>> {
>> + if (!task->pi_waiters_leftmost_copy)
>> return NULL;
>>
>> + return rb_entry(task->pi_waiters_leftmost_copy,
>> + struct rt_mutex_waiter, pi_tree_entry)->task;
>> }
> why ?! Why not keep a regular task_struct pointer and avoid this stuff?
I meant to make it semantically consistent, but I can change it since you think task_struct is better.
Regards,
Xunlei