tunnels: fix netns vs proto registration ordering
[safe/jmp/linux-2.6] / block / blk-cgroup.c
index 6bc99a3..1fa2654 100644 (file)
  *                   Nauman Rafique <nauman@google.com>
  */
 #include <linux/ioprio.h>
+#include <linux/seq_file.h>
+#include <linux/kdev_t.h>
+#include <linux/module.h>
+#include <linux/err.h>
 #include "blk-cgroup.h"
 
-extern void cfq_unlink_blkio_group(void *, struct blkio_group *);
+static DEFINE_SPINLOCK(blkio_list_lock);
+static LIST_HEAD(blkio_list);
 
 struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT };
+EXPORT_SYMBOL_GPL(blkio_root_cgroup);
+
+bool blkiocg_css_tryget(struct blkio_cgroup *blkcg)
+{
+       if (!css_tryget(&blkcg->css))
+               return false;
+       return true;
+}
+EXPORT_SYMBOL_GPL(blkiocg_css_tryget);
+
+void blkiocg_css_put(struct blkio_cgroup *blkcg)
+{
+       css_put(&blkcg->css);
+}
+EXPORT_SYMBOL_GPL(blkiocg_css_put);
 
 struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
 {
        return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id),
                            struct blkio_cgroup, css);
 }
+EXPORT_SYMBOL_GPL(cgroup_to_blkio_cgroup);
+
+void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
+                       unsigned long time, unsigned long sectors)
+{
+       blkg->time += time;
+       blkg->sectors += sectors;
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_stats);
 
 void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
-                               struct blkio_group *blkg, void *key)
+                       struct blkio_group *blkg, void *key, dev_t dev)
 {
        unsigned long flags;
 
@@ -37,7 +66,9 @@ void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
        /* Need to take css reference ? */
        cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path));
 #endif
+       blkg->dev = dev;
 }
+EXPORT_SYMBOL_GPL(blkiocg_add_blkio_group);
 
 static void __blkiocg_del_blkio_group(struct blkio_group *blkg)
 {
@@ -72,6 +103,7 @@ out:
        rcu_read_unlock();
        return ret;
 }
+EXPORT_SYMBOL_GPL(blkiocg_del_blkio_group);
 
 /* called under rcu_read_lock(). */
 struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key)
@@ -88,6 +120,7 @@ struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key)
 
        return NULL;
 }
+EXPORT_SYMBOL_GPL(blkiocg_lookup_group);
 
 #define SHOW_FUNCTION(__VAR)                                           \
 static u64 blkiocg_##__VAR##_read(struct cgroup *cgroup,               \
@@ -106,21 +139,86 @@ static int
 blkiocg_weight_write(struct cgroup *cgroup, struct cftype *cftype, u64 val)
 {
        struct blkio_cgroup *blkcg;
+       struct blkio_group *blkg;
+       struct hlist_node *n;
+       struct blkio_policy_type *blkiop;
 
        if (val < BLKIO_WEIGHT_MIN || val > BLKIO_WEIGHT_MAX)
                return -EINVAL;
 
        blkcg = cgroup_to_blkio_cgroup(cgroup);
+       spin_lock_irq(&blkcg->lock);
        blkcg->weight = (unsigned int)val;
+       hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
+               spin_lock(&blkio_list_lock);
+               list_for_each_entry(blkiop, &blkio_list, list)
+                       blkiop->ops.blkio_update_group_weight_fn(blkg,
+                                       blkcg->weight);
+               spin_unlock(&blkio_list_lock);
+       }
+       spin_unlock_irq(&blkcg->lock);
        return 0;
 }
 
+#define SHOW_FUNCTION_PER_GROUP(__VAR)                                 \
+static int blkiocg_##__VAR##_read(struct cgroup *cgroup,               \
+                       struct cftype *cftype, struct seq_file *m)      \
+{                                                                      \
+       struct blkio_cgroup *blkcg;                                     \
+       struct blkio_group *blkg;                                       \
+       struct hlist_node *n;                                           \
+                                                                       \
+       if (!cgroup_lock_live_group(cgroup))                            \
+               return -ENODEV;                                         \
+                                                                       \
+       blkcg = cgroup_to_blkio_cgroup(cgroup);                         \
+       rcu_read_lock();                                                \
+       hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {\
+               if (blkg->dev)                                          \
+                       seq_printf(m, "%u:%u %lu\n", MAJOR(blkg->dev),  \
+                                MINOR(blkg->dev), blkg->__VAR);        \
+       }                                                               \
+       rcu_read_unlock();                                              \
+       cgroup_unlock();                                                \
+       return 0;                                                       \
+}
+
+SHOW_FUNCTION_PER_GROUP(time);
+SHOW_FUNCTION_PER_GROUP(sectors);
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+SHOW_FUNCTION_PER_GROUP(dequeue);
+#endif
+#undef SHOW_FUNCTION_PER_GROUP
+
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
+                       unsigned long dequeue)
+{
+       blkg->dequeue += dequeue;
+}
+EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_dequeue_stats);
+#endif
+
 struct cftype blkio_files[] = {
        {
                .name = "weight",
                .read_u64 = blkiocg_weight_read,
                .write_u64 = blkiocg_weight_write,
        },
+       {
+               .name = "time",
+               .read_seq_string = blkiocg_time_read,
+       },
+       {
+               .name = "sectors",
+               .read_seq_string = blkiocg_sectors_read,
+       },
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+       {
+               .name = "dequeue",
+               .read_seq_string = blkiocg_dequeue_read,
+       },
+#endif
 };
 
 static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup)
@@ -135,6 +233,7 @@ static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup)
        unsigned long flags;
        struct blkio_group *blkg;
        void *key;
+       struct blkio_policy_type *blkiop;
 
        rcu_read_lock();
 remove_entry:
@@ -160,7 +259,10 @@ remove_entry:
         * we have more policies in place, we need some dynamic registration
         * of callback function.
         */
-       cfq_unlink_blkio_group(key, blkg);
+       spin_lock(&blkio_list_lock);
+       list_for_each_entry(blkiop, &blkio_list, list)
+               blkiop->ops.blkio_unlink_group_fn(key, blkg);
+       spin_unlock(&blkio_list_lock);
        goto remove_entry;
 done:
        free_css_id(&blkio_subsys, &blkcg->css);
@@ -241,3 +343,19 @@ struct cgroup_subsys blkio_subsys = {
        .subsys_id = blkio_subsys_id,
        .use_id = 1,
 };
+
+void blkio_policy_register(struct blkio_policy_type *blkiop)
+{
+       spin_lock(&blkio_list_lock);
+       list_add_tail(&blkiop->list, &blkio_list);
+       spin_unlock(&blkio_list_lock);
+}
+EXPORT_SYMBOL_GPL(blkio_policy_register);
+
+void blkio_policy_unregister(struct blkio_policy_type *blkiop)
+{
+       spin_lock(&blkio_list_lock);
+       list_del_init(&blkiop->list);
+       spin_unlock(&blkio_list_lock);
+}
+EXPORT_SYMBOL_GPL(blkio_policy_unregister);