[RFC/PATCH] powerpc: Move CPM command handling into the cpm drivers
vitb at kernel.crashing.org
Sun Nov 25 08:47:08 EST 2007
On Sat, 24 Nov 2007 18:53:34 +0100
Jochen Friedrich wrote:
> Hi Vitaly,
> >>> + printk(KERN_ERR "%s(): Not able to issue CPM command\n",
> >>> + __FUNCTION__);
> >>> + return -EIO;
> >> Do these need to be protected with a spin lock?
> > Even that might be not enough - we may have simultaneous call of
> > this func in non-smp case... I was thinking of some kind of
> > refcount, so one that is going to issue CPM command, must do say
> > pq_cpmp_get() and another driver won't be able to mangle with cpcr
> > while it's not done with previous request.
> > Yet I am not telling it was better the way it used to be - this
> > approach looks okay but needs some efforts to defend against
> > deadlocks while we are at it
> Wouldn't spin_lock_irqsave() prevent a deadlock?
yes, I believe it is OK for now.
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