cvs commit: src/sys/kern kern_intr.c

[John Baldwin]

On Friday 02 March 2007 13:45, Scott Long wrote:
> John Baldwin wrote:
> > On Friday 02 March 2007 12:28, Kris Kennaway wrote:
> >> On Fri, Mar 02, 2007 at 10:13:54AM -0700, Scott Long wrote:
> >>> John Baldwin wrote:
> >>>> jhb         2007-03-02 17:01:45 UTC
> >>>>
> >>>>  FreeBSD src repository
> >>>>
> >>>>  Modified files:
> >>>>    sys/kern             kern_intr.c 
> >>>>  Log:
> >>>>  - Don't do the interrupt storm protection stuff for software interrupt
> >>>>    handlers.
> >>>>  - Use pause() when throtting during an interrupt storm.
> >>>>  
> >>>>  Reported by:    kris (1)
> >>>>  
> >>>>  Revision  Changes    Path
> >>>>  1.142     +3 -2      src/sys/kern/kern_intr.c
> >>> Actually, having this helped detect a problem with a CAM driver.
> >>>
> >>> Scott
> >> I saw it under normal operation when doing a lot of loopback traffic
> >> on an 8-core.
> > 
> > Also, if it ever kicked in for softclock, the system would deadlock.
> > 
> 
> Can it be selectively enabled?

We could do that, sure.  The original intent was to prevent a storming 
level-triggered PCI interrupt to hang the machine though.  It was never 
really intended for swi's and having it be on for swi's was an oversight on 
my part.

-- 
John Baldwin