[PATCH v5 24/24] virt/steal_monitor: Add design check of preferred subset of active

[Shrikanth Hegde]

One of the main design construct that CONFIG_PREFERRED_CPU maintains is
that preferred is always subset of active. Force that in any future arch
specific implementations.

Signed-off-by: Shrikanth Hegde <sshegde@xxxxxxxxxxxxx>
---
v4->v5:
- new patch

 drivers/virt/steal_monitor/sm_core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/virt/steal_monitor/sm_core.c b/drivers/virt/steal_monitor/sm_core.c
index f5b0e568eb32..82beb2b94083 100644
--- a/drivers/virt/steal_monitor/sm_core.c
+++ b/drivers/virt/steal_monitor/sm_core.c
@@ -80,6 +80,9 @@ static void compute_preferred_cpus_work(struct work_struct *work)
 	/* At least one core is kept as preferred */
 	WARN_ON(cpumask_empty(cpu_preferred_mask));
 
+	/* Maintain design construct */
+	WARN_ON(!cpumask_subset(cpu_preferred_mask, cpu_active_mask));
+
 	/* Warn if interval_ms is set to 0, that might cause lockup. */
 	if (unlikely(sm_core_ctx.interval_ms == 0)) {
 		WARN_ON(1);
-- 
2.47.3