Commit 9d6a986c authored by Vivek Goyal's avatar Vivek Goyal Committed by Jens Axboe
Browse files

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: default avatarVivek Goyal <vgoyal@redhat.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent b69f2292

block/blk-cgroup.c

+22 −0
Original line number Diff line number Diff line
@@ -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 @@ int blkiocg_del_blkio_group(struct blkio_group *blkg) 
	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[] = {

block/blk-cgroup.h

+3 −0
Original line number Diff line number Diff line
@@ -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 {

block/cfq-iosched.c

+2 −2
Original line number Diff line number Diff line
@@ -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;

}