Merge tag 'libnvdimm-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdim...

[linux-2.6-microblaze.git] / include / linux / energy_model.h

diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h
index 3f221db..1834752 100644 (file)
--- a/include/linux/energy_model.h
+++ b/include/linux/energy_model.h
@@ -53,6 +53,22 @@ struct em_perf_domain {
 #ifdef CONFIG_ENERGY_MODEL
 #define EM_MAX_POWER 0xFFFF
 
+/*
+ * Increase resolution of energy estimation calculations for 64-bit
+ * architectures. The extra resolution improves decision made by EAS for the
+ * task placement when two Performance Domains might provide similar energy
+ * estimation values (w/o better resolution the values could be equal).
+ *
+ * We increase resolution only if we have enough bits to allow this increased
+ * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
+ * are pretty high and the returns do not justify the increased costs.
+ */
+#ifdef CONFIG_64BIT
+#define em_scale_power(p) ((p) * 1000)
+#else
+#define em_scale_power(p) (p)
+#endif
+
 struct em_data_callback {
        /**
         * active_power() - Provide power at the next performance state of