From d92e69a17a36b1d6d4c4f3f77f64a9957666badf Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Wed, 12 May 2010 08:47:10 +0100 Subject: [PATCH] credit2: Fix tasklets Signed-off-by: George Dunlap --- xen/common/sched_credit2.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/xen/common/sched_credit2.c b/xen/common/sched_credit2.c index fe4fa3344d..14cea94e9d 100644 --- a/xen/common/sched_credit2.c +++ b/xen/common/sched_credit2.c @@ -921,18 +921,16 @@ csched_schedule( /* Update credits */ burn_credits(rqd, scurr, now); - /* Tasklet work (which runs in idle VCPU context) overrides all else. */ - if ( tasklet_work_scheduled ) - { - snext = CSCHED_VCPU(idle_vcpu[cpu]); - goto out; - } - /* * Select next runnable local VCPU (ie top of local runq). * * If the current vcpu is runnable, and has higher credit than - * the next guy on the queue (or there is noone else), we want to run him again. + * the next guy on the queue (or there is noone else), we want to + * run him again. + * + * If there's tasklet work to do, we want to chose the idle vcpu + * for this processor, and mark the current for delayed runqueue + * add. * * If the current vcpu is runnable, and the next guy on the queue * has higher credit, we want to mark current for delayed runqueue @@ -941,7 +939,7 @@ csched_schedule( * If the current vcpu is not runnable, we want to chose the idle * vcpu for this processor. */ - if ( list_empty(runq) ) + if ( list_empty(runq) || tasklet_work_scheduled ) snext = CSCHED_VCPU(idle_vcpu[cpu]); else snext = __runq_elem(runq->next); @@ -949,9 +947,10 @@ csched_schedule( if ( !is_idle_vcpu(current) && vcpu_runnable(current) ) { /* If the current vcpu is runnable, and has higher credit - * than the next on the runqueue, run him again. + * than the next on the runqueue, and isn't being preempted + * by a tasklet, run him again. * Otherwise, set him for delayed runq add. */ - if ( scurr->credit > snext->credit) + if ( !tasklet_work_scheduled && scurr->credit > snext->credit) snext = scurr; else set_bit(__CSFLAG_delayed_runq_add, &scurr->flags); @@ -998,7 +997,6 @@ csched_schedule( snext->vcpu->processor = cpu; /* Safe because lock for old processor is held */ } - out: /* * Return task to run next... */ -- 2.39.5