preempt_disable and softirq

preempt_disable and softirq

[Venkat Subbiah]

Does disabling preemption by calling preempt_disable() cause softirqs
on the local cpu to be disabled too?

I believe drivers napi polling functions is being called when the
current cpu is holding on to a read lock of tasklist_lock. read_lock()
itself disables preemption.

An easy way to check in the napi polling functions that the current
cpu is not holding on to tasklist_lock? Of course this is mute if
softirqs itself cannot execute when premption is disabled.

PS: I am not subscribed to the groups. Please CC me on your answer.

Thanks,
Venkat

Re: preempt_disable and softirq

[Peter Zijlstra]

On Sat, 2011-08-06 at 19:03 -0700, Venkat Subbiah wrote:
> Does disabling preemption by calling preempt_disable() cause softirqs
> on the local cpu to be disabled too? 

No.