sched: add arch_scale_min_freq_capacity to track minimum capacity caps
If the minimum capacity of a group is capped by userspace or internal
dependencies which are not otherwise visible to the scheduler, we need
a way to see these and integrate this information into the energy
calculations and task placement decisions we make.
Add arch_scale_min_freq_capacity to determine the lowest capacity which
a specific cpu can provide under the current set of known constraints.
Change-Id: Ied4a1dc0982bbf42cb5ea2f27201d4363db59705
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 9400de0..646ff3c 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1591,6 +1591,18 @@
}
#endif
+#ifndef arch_scale_min_freq_capacity
+static __always_inline
+unsigned long arch_scale_min_freq_capacity(struct sched_domain *sd, int cpu)
+{
+ /*
+ * Multiplied with any capacity value, this scale factor will return
+ * 0, which represents an un-capped state
+ */
+ return 0;
+}
+#endif
+
#ifndef arch_scale_cpu_capacity
static __always_inline
unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)