sched/core: Better document the try_to_wake_up() barriers

[cascardo/linux.git] / kernel / sched / sched.h

diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 6d2a119..b242775 100644 (file)
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -84,6 +84,10 @@ static inline void update_cpu_load_active(struct rq *this_rq) { }
  */
 #define RUNTIME_INF    ((u64)~0ULL)
 
+static inline int idle_policy(int policy)
+{
+       return policy == SCHED_IDLE;
+}
 static inline int fair_policy(int policy)
 {
        return policy == SCHED_NORMAL || policy == SCHED_BATCH;
@@ -98,6 +102,11 @@ static inline int dl_policy(int policy)
 {
        return policy == SCHED_DEADLINE;
 }
+static inline bool valid_policy(int policy)
+{
+       return idle_policy(policy) || fair_policy(policy) ||
+               rt_policy(policy) || dl_policy(policy);
+}
 
 static inline int task_has_rt_policy(struct task_struct *p)
 {
@@ -109,11 +118,6 @@ static inline int task_has_dl_policy(struct task_struct *p)
        return dl_policy(p->policy);
 }
 
-static inline bool dl_time_before(u64 a, u64 b)
-{
-       return (s64)(a - b) < 0;
-}
-
 /*
  * Tells if entity @a should preempt entity @b.
  */
@@ -1003,17 +1007,7 @@ extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
 
-#ifdef CONFIG_NUMA_BALANCING
-#define sched_feat_numa(x) sched_feat(x)
-#ifdef CONFIG_SCHED_DEBUG
-#define numabalancing_enabled sched_feat_numa(NUMA)
-#else
-extern bool numabalancing_enabled;
-#endif /* CONFIG_SCHED_DEBUG */
-#else
-#define sched_feat_numa(x) (0)
-#define numabalancing_enabled (0)
-#endif /* CONFIG_NUMA_BALANCING */
+extern struct static_key_false sched_numa_balancing;
 
 static inline u64 global_rt_period(void)
 {
@@ -1079,6 +1073,9 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
         * We must ensure this doesn't happen until the switch is completely
         * finished.
         *
+        * In particular, the load of prev->state in finish_task_switch() must
+        * happen before this.
+        *
         * Pairs with the control dependency and rmb in try_to_wake_up().
         */
        smp_store_release(&prev->on_cpu, 0);
@@ -1157,16 +1154,18 @@ static const u32 prio_to_wmult[40] = {
  /*  15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
 };
 
-#define ENQUEUE_WAKEUP         1
-#define ENQUEUE_HEAD           2
+#define ENQUEUE_WAKEUP         0x01
+#define ENQUEUE_HEAD           0x02
 #ifdef CONFIG_SMP
-#define ENQUEUE_WAKING         4       /* sched_class::task_waking was called */
+#define ENQUEUE_WAKING         0x04    /* sched_class::task_waking was called */
 #else
-#define ENQUEUE_WAKING         0
+#define ENQUEUE_WAKING         0x00
 #endif
-#define ENQUEUE_REPLENISH      8
+#define ENQUEUE_REPLENISH      0x08
+#define ENQUEUE_RESTORE        0x10
 
-#define DEQUEUE_SLEEP          1
+#define DEQUEUE_SLEEP          0x01
+#define DEQUEUE_SAVE           0x02
 
 #define RETRY_TASK             ((void *)-1UL)
 
@@ -1194,7 +1193,7 @@ struct sched_class {
 
 #ifdef CONFIG_SMP
        int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
-       void (*migrate_task_rq)(struct task_struct *p, int next_cpu);
+       void (*migrate_task_rq)(struct task_struct *p);
 
        void (*task_waking) (struct task_struct *task);
        void (*task_woken) (struct rq *this_rq, struct task_struct *task);
@@ -1227,7 +1226,7 @@ struct sched_class {
        void (*update_curr) (struct rq *rq);
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
-       void (*task_move_group) (struct task_struct *p, int on_rq);
+       void (*task_move_group) (struct task_struct *p);
 #endif
 };
 
@@ -1405,6 +1404,17 @@ unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
 }
 #endif
 
+#ifndef arch_scale_cpu_capacity
+static __always_inline
+unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
+{
+       if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
+               return sd->smt_gain / sd->span_weight;
+
+       return SCHED_CAPACITY_SCALE;
+}
+#endif
+
 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
 {
        rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq));