Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 239d1fc0 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by Thomas Gleixner
Browse files

xen: don't worry about preempt during xen_irq_enable() 



When enabling interrupts, we don't need to worry about preemption,
because we either enter with interrupts disabled - so no preemption -
or the caller is confused and is re-enabling interrupts on some
indeterminate processor.

Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 2956a351

arch/x86/xen/enlighten.c

+5 −5
Original line number Diff line number Diff line
@@ -235,13 +235,13 @@ static void xen_irq_enable(void) 
{

	struct vcpu_info *vcpu;



	/* There's a one instruction preempt window here.  We need to

	   make sure we're don't switch CPUs between getting the vcpu

	   pointer and updating the mask. */

	preempt_disable();

	/* We don't need to worry about being preempted here, since

	   either a) interrupts are disabled, so no preemption, or b)

	   the caller is confused and is trying to re-enable interrupts

	   on an indeterminate processor. */



	vcpu = x86_read_percpu(xen_vcpu);

	vcpu->evtchn_upcall_mask = 0;

	preempt_enable_no_resched();



	/* Doesn't matter if we get preempted here, because any

	   pending event will get dealt with anyway. */