Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / include / linux / sched.h

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 885c4f2..aaf71e0 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -315,7 +315,6 @@ extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
                                  void __user *buffer,
                                  size_t *lenp, loff_t *ppos);
 extern unsigned int  softlockup_panic;
-extern int softlockup_thresh;
 void lockup_detector_init(void);
 #else
 static inline void touch_softlockup_watchdog(void)
@@ -787,17 +786,39 @@ enum cpu_idle_type {
 };
 
 /*
- * sched-domains (multiprocessor balancing) declarations:
+ * Increase resolution of nice-level calculations for 64-bit architectures.
+ * The extra resolution improves shares distribution and load balancing of
+ * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
+ * hierarchies, especially on larger systems. This is not a user-visible change
+ * and does not change the user-interface for setting shares/weights.
+ *
+ * We increase resolution only if we have enough bits to allow this increased
+ * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
+ * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
+ * increased costs.
  */
+#if BITS_PER_LONG > 32
+# define SCHED_LOAD_RESOLUTION 10
+# define scale_load(w)         ((w) << SCHED_LOAD_RESOLUTION)
+# define scale_load_down(w)    ((w) >> SCHED_LOAD_RESOLUTION)
+#else
+# define SCHED_LOAD_RESOLUTION 0
+# define scale_load(w)         (w)
+# define scale_load_down(w)    (w)
+#endif
 
-/*
- * Increase resolution of nice-level calculations:
- */
-#define SCHED_LOAD_SHIFT       10
+#define SCHED_LOAD_SHIFT       (10 + SCHED_LOAD_RESOLUTION)
 #define SCHED_LOAD_SCALE       (1L << SCHED_LOAD_SHIFT)
 
-#define SCHED_LOAD_SCALE_FUZZ  SCHED_LOAD_SCALE
+/*
+ * Increase resolution of cpu_power calculations
+ */
+#define SCHED_POWER_SHIFT      10
+#define SCHED_POWER_SCALE      (1L << SCHED_POWER_SHIFT)
 
+/*
+ * sched-domains (multiprocessor balancing) declarations:
+ */
 #ifdef CONFIG_SMP
 #define SD_LOAD_BALANCE                0x0001  /* Do load balancing on this domain. */
 #define SD_BALANCE_NEWIDLE     0x0002  /* Balance when about to become idle */