On 09/01/15 16:02, Konrad Rzeszutek Wilk wrote: > On Thu, Jan 08, 2015 at 04:13:03PM +0000, Jan Beulich wrote: >> ... as generally being a cheaper operation. > I was wondering if it would be possible to change some of the > EFLAGS after when we go in the 'cpu_relax' - and an interrupt > happens, we process it, alter the EFLAGS, then when we are > done, the EFLAGS are different - which the original code would > save when it was done sitting on the cpu_relax() loop. > > Actually that sounds bad - we only want to restore the flags > that we had when going in this spin lock. Would make sense > to add an ASSERT to check for flags being different from the > EFLAGS?
local_irq_restore() only restores the interrupt flag from flags. All other bits in EFLAGS are unmodified. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
