Re: [PATCH] move put_task_struct() reaping into a thread [Re: 2.6.18-rt1]

Ingo Molnar
2006-09-21T13:07:46Z

* Esben Nielsen <nielsen.esben@gogglemail.com> wrote:

> The whole point is to defer those frees to a task. In -rt call_rcu()
> is abused to do that in the case of put_task_struct(). But it is abuse
> since call_rcu() is much more resourcefull than simply defering to a
> task.

nah, it's not nearly as "resourceful" as having a separate thread for
each teardown type ... It is also the easiest to maintain way of tearing
down stuff, so i'm quite happy with it. If then i'll move the mm_struct
teardown to RCU too. (Later on we can do some 'fastpath RCU' thing
perhaps, to force an RCU batch of work through quiescent state)

but this is quite likely a side-issue that probably has no connection to
the crash Bill was seeing. Whether separate teardown thread or
softirq-rcu, it's a separate thread already.

Ingo