On Fri, 2002-11-22 at 03:54, dan carpenter wrote:
(Next time trim your CC list: none of those poor guys needed this
email..)
> In drivers/net/tokenring/3c359.c xl_interrupt() calls schedule().
> The path from xl_interupt to schedule is:
> xl_rx ==> netif_rx ==>
> kfree_skb ==> __kfree_skb ==>
> secpath_put ==> __secpath_destroy ==>
> xfrm_state_put ==> __xfrm_state_destroy ==> xfrm_put_type ==>
> module_put ==> put_cpu ==> preempt_schedule ==> schedule
Are you actually seeing this code path or is this just what your script
is showing you?
preempt_schedule() will not call schedule() if the preempt_count is
non-zero. Inside an interrupt handler, it is always at least one. So
nothing will drop it to zero, and we will never preempt.
> The third thing I was wondering is: xl_interupt is holding a
> spin_lock(&xl_priv->xl_lock). I know that you're not supposed to call shedule()
> while holding a spin lock, but is it ok to call preempt_schedule()?
Same as above. preempt_schedule() only calls schedule when
preempt_count is zero. It is not if you hold a lock, and it is not
inside an interrupt handler.
Robert Love
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This archive was generated by hypermail 2b29 : Sat Nov 23 2002 - 22:00:39 EST