svn commit: r271707 - stable/10/sys/kern

[Alan Cox]

On 09/17/2014 11:46, Alexander Motin wrote:
> On 17.09.2014 19:16, Andrey Chernov wrote:
>> On 17.09.2014 18:06, Alexander Motin wrote:
>>> +	/*
>>> +	 * Make sure that tdq_load updated before calling this function
>>> +	 * is globally visible before we read tdq_cpu_idle.  Idle thread
>>> +	 * accesses both of them without locks, and the order is important.
>>> +	 */
>>> +	mb();
>>> +
>>>  	if (TD_IS_IDLETHREAD(ctd)) {
>> I don't understand this comment's first phrase with two verbs. Copy &
>> paste result?
> No, only possibly missing commas around "updated before calling this
> function".


Commas alone don't fix the problem.  I think what you're trying to say is:

"Make sure that our caller's earlier update to tdq_load is globally
visible before we read tdq_cpu_idle."


>> I also don't see tdq_load access in this function.
> It is incremented by tdq_load_add(), called by tdq_add(), called by
> sched_add(), just before calling tdq_notify().
>