X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=kernel%2Fsched%2Fcore.c;h=495bc41907d6288122d7ab32428eb12f82324c97;hb=8ceb7db7d2cfde150b2906fccb0483f3ed54b4b4;hp=1df6da0094f01448ff477f6c1b963b2b6c80c8f6;hpb=73dadd0ed30ff274d645b3b2ea90e897608947bc;p=firefly-linux-kernel-4.4.55.git

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 1df6da0094f0..495bc41907d6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6037,6 +6037,7 @@ static int sd_degenerate(struct sched_domain *sd)
 			 SD_BALANCE_FORK |
 			 SD_BALANCE_EXEC |
 			 SD_SHARE_CPUCAPACITY |
+			 SD_ASYM_CPUCAPACITY |
 			 SD_SHARE_PKG_RESOURCES |
 			 SD_SHARE_POWERDOMAIN |
 			 SD_SHARE_CAP_STATES)) {
@@ -6068,6 +6069,7 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
 				SD_BALANCE_NEWIDLE |
 				SD_BALANCE_FORK |
 				SD_BALANCE_EXEC |
+				SD_ASYM_CPUCAPACITY |
 				SD_SHARE_CPUCAPACITY |
 				SD_SHARE_PKG_RESOURCES |
 				SD_PREFER_SIBLING |
@@ -6153,6 +6155,9 @@ static int init_rootdomain(struct root_domain *rd)
 		goto free_rto_mask;
 
 	init_max_cpu_capacity(&rd->max_cpu_capacity);
+
+	rd->max_cap_orig_cpu = rd->min_cap_orig_cpu = -1;
+
 	return 0;
 
 free_rto_mask:
@@ -6457,6 +6462,7 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
 		 */
 		sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span);
 		sg->sgc->max_capacity = SCHED_CAPACITY_SCALE;
+		sg->sgc->min_capacity = SCHED_CAPACITY_SCALE;
 
 		/*
 		 * Make sure the first group of this domain contains the
@@ -6749,11 +6755,19 @@ static int sched_domains_curr_level;
 /*
  * SD_flags allowed in topology descriptions.
  *
- * SD_SHARE_CPUCAPACITY      - describes SMT topologies
- * SD_SHARE_PKG_RESOURCES - describes shared caches
- * SD_NUMA                - describes NUMA topologies
- * SD_SHARE_POWERDOMAIN   - describes shared power domain
- * SD_SHARE_CAP_STATES    - describes shared capacity states
+ * These flags are purely descriptive of the topology and do not prescribe
+ * behaviour. Behaviour is artificial and mapped in the below sd_init()
+ * function:
+ *
+ *   SD_SHARE_CPUCAPACITY   - describes SMT topologies
+ *   SD_SHARE_PKG_RESOURCES - describes shared caches
+ *   SD_NUMA                - describes NUMA topologies
+ *   SD_SHARE_POWERDOMAIN   - describes shared power domain
+ *   SD_ASYM_CPUCAPACITY    - describes mixed capacity topologies
+ *   SD_SHARE_CAP_STATES    - describes shared capacity states
+ *
+ * Odd one out, which beside describing the topology has a quirk also
+ * prescribes the desired behaviour that goes along with it:
  *
  * Odd one out:
  * SD_ASYM_PACKING        - describes SMT quirks
@@ -6763,11 +6777,13 @@ static int sched_domains_curr_level;
 	 SD_SHARE_PKG_RESOURCES |	\
 	 SD_NUMA |			\
 	 SD_ASYM_PACKING |		\
+	 SD_ASYM_CPUCAPACITY |		\
 	 SD_SHARE_POWERDOMAIN |		\
 	 SD_SHARE_CAP_STATES)
 
 static struct sched_domain *
-sd_init(struct sched_domain_topology_level *tl, int cpu)
+sd_init(struct sched_domain_topology_level *tl,
+	struct sched_domain *child, int cpu)
 {
 	struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu);
 	int sd_weight, sd_flags = 0;
@@ -6819,6 +6835,7 @@ sd_init(struct sched_domain_topology_level *tl, int cpu)
 		.smt_gain		= 0,
 		.max_newidle_lb_cost	= 0,
 		.next_decay_max_lb_cost	= jiffies,
+		.child			= child,
 #ifdef CONFIG_SCHED_DEBUG
 		.name			= tl->name,
 #endif
@@ -6828,6 +6845,13 @@ sd_init(struct sched_domain_topology_level *tl, int cpu)
 	 * Convert topological properties into behaviour.
 	 */
 
+	if (sd->flags & SD_ASYM_CPUCAPACITY) {
+		struct sched_domain *t = sd;
+
+		for_each_lower_domain(t)
+			t->flags |= SD_BALANCE_WAKE;
+	}
+
 	if (sd->flags & SD_SHARE_CPUCAPACITY) {
 		sd->flags |= SD_PREFER_SIBLING;
 		sd->imbalance_pct = 110;
@@ -7274,16 +7298,13 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
 		const struct cpumask *cpu_map, struct sched_domain_attr *attr,
 		struct sched_domain *child, int cpu)
 {
-	struct sched_domain *sd = sd_init(tl, cpu);
-	if (!sd)
-		return child;
+	struct sched_domain *sd = sd_init(tl, child, cpu);
 
 	cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu));
 	if (child) {
 		sd->level = child->level + 1;
 		sched_domain_level_max = max(sched_domain_level_max, sd->level);
 		child->parent = sd;
-		sd->child = child;
 
 		if (!cpumask_subset(sched_domain_span(child),
 				    sched_domain_span(sd))) {
@@ -7314,7 +7335,6 @@ static int build_sched_domains(const struct cpumask *cpu_map,
 	enum s_alloc alloc_state;
 	struct sched_domain *sd;
 	struct s_data d;
-	struct rq *rq = NULL;
 	int i, ret = -ENOMEM;
 
 	alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
@@ -7368,8 +7388,19 @@ static int build_sched_domains(const struct cpumask *cpu_map,
 	/* Attach the domains */
 	rcu_read_lock();
 	for_each_cpu(i, cpu_map) {
-		rq = cpu_rq(i);
+		int max_cpu = READ_ONCE(d.rd->max_cap_orig_cpu);
+		int min_cpu = READ_ONCE(d.rd->min_cap_orig_cpu);
+
+		if ((max_cpu < 0) || (cpu_rq(i)->cpu_capacity_orig >
+		    cpu_rq(max_cpu)->cpu_capacity_orig))
+			WRITE_ONCE(d.rd->max_cap_orig_cpu, i);
+
+		if ((min_cpu < 0) || (cpu_rq(i)->cpu_capacity_orig <
+		    cpu_rq(min_cpu)->cpu_capacity_orig))
+			WRITE_ONCE(d.rd->min_cap_orig_cpu, i);
+
 		sd = *per_cpu_ptr(d.sd, i);
+
 		cpu_attach_domain(sd, d.rd, i);
 	}
 	rcu_read_unlock();