blkio: Export some symbols from blkio as its user CFQ can be a module

o blkio controller is inside the kernel and cfq makes use of interfaces
  exported by blkio. CFQ can be a module too, hence export symbols used
  by CFQ.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Vivek Goyal 2009-12-04 10:36:41 -05:00 committed by Jens Axboe
parent b69f229206
commit 9d6a986c0b
3 changed files with 27 additions and 2 deletions

View File

@ -13,16 +13,33 @@
#include <linux/ioprio.h>
#include <linux/seq_file.h>
#include <linux/kdev_t.h>
#include <linux/module.h>
#include "blk-cgroup.h"
#include "cfq-iosched.h"
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)
@ -30,6 +47,7 @@ void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
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, dev_t dev)
@ -47,6 +65,7 @@ void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
#endif
blkg->dev = dev;
}
EXPORT_SYMBOL_GPL(blkiocg_add_blkio_group);
static void __blkiocg_del_blkio_group(struct blkio_group *blkg)
{
@ -81,6 +100,7 @@ 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)
@ -97,6 +117,7 @@ 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, \
@ -166,6 +187,7 @@ void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
{
blkg->dequeue += dequeue;
}
EXPORT_SYMBOL_GPL(blkiocg_update_blkio_group_dequeue_stats);
#endif
struct cftype blkio_files[] = {

View File

@ -43,6 +43,9 @@ struct blkio_group {
unsigned long sectors;
};
extern bool blkiocg_css_tryget(struct blkio_cgroup *blkcg);
extern void blkiocg_css_put(struct blkio_cgroup *blkcg);
#else
struct blkio_group {

View File

@ -961,7 +961,7 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
unsigned int major, minor;
/* Do we need to take this reference */
if (!css_tryget(&blkcg->css))
if (!blkiocg_css_tryget(blkcg))
return NULL;;
cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key));
@ -994,7 +994,7 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list);
done:
css_put(&blkcg->css);
blkiocg_css_put(blkcg);
return cfqg;
}