Messages in this thread | | | Date | Thu, 7 Apr 2005 20:40:44 +0200 (MEST) | From | Mikael Pettersson <> | Subject | Re: 2.6.12-rc2 in_atomic() picks up preempt_disable() |
| |
On Thu, 07 Apr 2005 12:17:37 +0200, Arjan van de Ven wrote: >On Thu, 2005-04-07 at 20:10 +1000, Keith Owens wrote: >> 2.6.12-rc2, with CONFIG_PREEMPT and CONFIG_PREEMPT_DEBUG. The >> in_atomic() macro thinks that preempt_disable() indicates an atomic >> region so calls to __might_sleep() result in a stack trace. > >but you're not allowed to schedule when preempt is disabled!
That sounds draconian. Where is that requirement stated?
A preempt-disabled region ought to have the same semantics as in a CONFIG_PREEMPT=n kernel, and since schedule is Ok in the latter case it should be Ok in the former too.
All that preempt_disable() should do is prevent involuntary schedules. But the conditional schedules introduced by may-sleep functions are _voluntary_, so there's no reason to forbid them. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |