---

yaml --- r: 145716 b: refs/heads/master c: 4200efd h: refs/heads/master v: v3
git-mirror · May 19, 2009 · 0a4d5f1 · 0a4d5f1
1 parent b629f0d
commit 0a4d5f1
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Showing 3 changed files with 26 additions and 6 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 2d02494f5a90f2e4b3c4c6acc85ec94674cdc431
+refs/heads/master: 4200efd9acda4accf24640f1e77d24fdcdb524df
diff --git a/trunk/include/linux/sched.h b/trunk/include/linux/sched.h
@@ -839,7 +839,17 @@ struct sched_group {
 	 */
 	u32 reciprocal_cpu_power;
 
-	unsigned long cpumask[];
+	/*
+	 * The CPUs this group covers.
+	 *
+	 * NOTE: this field is variable length. (Allocated dynamically
+	 * by attaching extra space to the end of the structure,
+	 * depending on how many CPUs the kernel has booted up with)
+	 *
+	 * It is also be embedded into static data structures at build
+	 * time. (See 'struct static_sched_group' in kernel/sched.c)
+	 */
+	unsigned long cpumask[0];
 };
 
 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
@@ -925,8 +935,17 @@ struct sched_domain {
 	char *name;
 #endif
 
-	/* span of all CPUs in this domain */
-	unsigned long span[];
+	/*
+	 * Span of all CPUs in this domain.
+	 *
+	 * NOTE: this field is variable length. (Allocated dynamically
+	 * by attaching extra space to the end of the structure,
+	 * depending on how many CPUs the kernel has booted up with)
+	 *
+	 * It is also be embedded into static data structures at build
+	 * time. (See 'struct static_sched_domain' in kernel/sched.c)
+	 */
+	unsigned long span[0];
 };
 
 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)

diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
@@ -7948,8 +7948,9 @@ int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
 
 /*
  * The cpus mask in sched_group and sched_domain hangs off the end.
- * FIXME: use cpumask_var_t or dynamic percpu alloc to avoid wasting space
- * for nr_cpu_ids < CONFIG_NR_CPUS.
+ *
+ * ( See the the comments in include/linux/sched.h:struct sched_group
+ *   and struct sched_domain. )
  */
 struct static_sched_group {
 	struct sched_group sg;