[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[PATCH v3 2/3] xen/sched: don't call sync_vcpu_execstate() in sched_unit_migrate_finish()

With support of core scheduling sched_unit_migrate_finish() gained a
call of sync_vcpu_execstate() as it was believed to be called as a
result of vcpu migration in any case.

In case of migrating a vcpu away from a physical cpu for a short period
of time ionly without ever being scheduled on the selected new cpu this
might not be true, so drop the call and let the lazy state syncing do
its job.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
- new patch
 xen/common/sched/core.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/xen/common/sched/core.c b/xen/common/sched/core.c
index 5df66cbf9b..cb49a8bc02 100644
--- a/xen/common/sched/core.c
+++ b/xen/common/sched/core.c
@@ -1078,12 +1078,7 @@ static void sched_unit_migrate_finish(struct sched_unit 
     sched_spin_unlock_double(old_lock, new_lock, flags);
     if ( old_cpu != new_cpu )
-    {
-        /* Vcpus are moved to other pcpus, commit their states to memory. */
-        for_each_sched_unit_vcpu ( unit, v )
-            sync_vcpu_execstate(v);
-    }
     /* Wake on new CPU. */
     for_each_sched_unit_vcpu ( unit, v )



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.