Messages in this thread | | | Date | Sun, 15 May 2005 15:01:03 +0100 | From | Russell King <> | Subject | Re: tickle nmi watchdog whilst doing serial writes. |
| |
On Sun, May 15, 2005 at 02:20:14PM +0200, Andi Kleen wrote: > Then someone needs to convince Linus to export touch_nmi_watchdog > again. > > Or how about checking if interrupts are off here (iirc we have > a generic function for that now) and then using > a smaller timeout and otherwise schedule_timeout() ?
The interrupt state doesn't tell us whether we can schedule. It tells us when we can't schedule, which is different from when we can. For example:
spin_lock(foo_lock); ... printk("blah blah blah\n"); ... spin_unlock(foo_lock);
This context is non-preemptable, but doesn't have IRQs disabled. The solution would be to keep a "spinlock depth" counter, but obviously that's not a possibility.
I would agree that the most correct thing to do would be to export touch_nmi_watchdog()... if only Linus would accept the arguments _for_ exporting it.
-- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core - 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/
| |