sched debug: add name to sched_domain sysctl entries

add /proc/sys/kernel/sched_domain/cpu0/domain0/name, to make
it easier to see which specific scheduler domain remained at
that entry.

Since we process the scheduler domain tree and
simplify it, it's not always immediately clear during debugging
which domain came from where.

depends on CONFIG_SCHED_DEBUG=y.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/include/linux/sched.h b/include/linux/sched.h
index d8e699b558586ac0ee0f3f46e6304e6ac2d5057f..5d0819ee442a471e840b37a5ea1c35ee13030d25 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -824,6 +824,9 @@ struct sched_domain {
        unsigned int ttwu_move_affine;
        unsigned int ttwu_move_balance;
 #endif
+#ifdef CONFIG_SCHED_DEBUG
+       char *name;
+#endif
 };
 
 extern void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,

diff --git a/kernel/sched.c b/kernel/sched.c
index 9715f4ce6cfe4141bf4d06d9714ac05aa8cfe8f1..6f230596bd0c1d21a2c68ffbff8207e93dcd65b5 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6351,7 +6351,7 @@ set_table_entry(struct ctl_table *entry,
 static struct ctl_table *
 sd_alloc_ctl_domain_table(struct sched_domain *sd)
 {
-       struct ctl_table *table = sd_alloc_ctl_entry(12);
+       struct ctl_table *table = sd_alloc_ctl_entry(13);
 
        if (table == NULL)
                return NULL;
@@ -6379,7 +6379,9 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd)
                sizeof(int), 0644, proc_dointvec_minmax);
        set_table_entry(&table[10], "flags", &sd->flags,
                sizeof(int), 0644, proc_dointvec_minmax);
-       /* &table[11] is terminator */
+       set_table_entry(&table[11], "name", sd->name,
+               CORENAME_MAX_SIZE, 0444, proc_dostring);
+       /* &table[12] is terminator */
 
        return table;
 }
@@ -7263,13 +7265,21 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
  * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
  */
 
+#ifdef CONFIG_SCHED_DEBUG
+# define SD_INIT_NAME(sd, type)                sd->name = #type
+#else
+# define SD_INIT_NAME(sd, type)                do { } while (0)
+#endif
+
 #define        SD_INIT(sd, type)       sd_init_##type(sd)
+
 #define SD_INIT_FUNC(type)     \
 static noinline void sd_init_##type(struct sched_domain *sd)   \
 {                                                              \
        memset(sd, 0, sizeof(*sd));                             \
        *sd = SD_##type##_INIT;                                 \
        sd->level = SD_LV_##type;                               \
+       SD_INIT_NAME(sd, type);                                 \
 }
 
 SD_INIT_FUNC(CPU)