aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorBen Blum <bblum@andrew.cmu.edu>2010-03-10 18:22:11 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2010-03-12 18:52:36 -0500
commit67523c48aa74d5637848edeccf285af1c60bf14a (patch)
treeebd14992e210c8dfb503ae5fdffc1f5392ad52df
parent8ca712ea84728531d36841ca8f98f9e8680bcf4e (diff)
cgroups: blkio subsystem as module
Modify the Block I/O cgroup subsystem to be able to be built as a module. As the CFQ disk scheduler optionally depends on blk-cgroup, config options in block/Kconfig, block/Kconfig.iosched, and block/blk-cgroup.h are enhanced to support the new module dependency. Signed-off-by: Ben Blum <bblum@andrew.cmu.edu> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--block/Kconfig2
-rw-r--r--block/Kconfig.iosched2
-rw-r--r--block/blk-cgroup.c53
-rw-r--r--block/blk-cgroup.h10
-rw-r--r--include/linux/iocontext.h2
-rw-r--r--kernel/cgroup.c9
6 files changed, 61 insertions, 17 deletions
diff --git a/block/Kconfig b/block/Kconfig
index e20fbde0875c..62a5921321cd 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -78,7 +78,7 @@ config BLK_DEV_INTEGRITY
78 Protection. If in doubt, say N. 78 Protection. If in doubt, say N.
79 79
80config BLK_CGROUP 80config BLK_CGROUP
81 bool 81 tristate
82 depends on CGROUPS 82 depends on CGROUPS
83 default n 83 default n
84 ---help--- 84 ---help---
diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched
index b71abfb0d726..fc71cf071fb2 100644
--- a/block/Kconfig.iosched
+++ b/block/Kconfig.iosched
@@ -23,6 +23,7 @@ config IOSCHED_DEADLINE
23 23
24config IOSCHED_CFQ 24config IOSCHED_CFQ
25 tristate "CFQ I/O scheduler" 25 tristate "CFQ I/O scheduler"
26 select BLK_CGROUP if CFQ_GROUP_IOSCHED
26 default y 27 default y
27 ---help--- 28 ---help---
28 The CFQ I/O scheduler tries to distribute bandwidth equally 29 The CFQ I/O scheduler tries to distribute bandwidth equally
@@ -35,7 +36,6 @@ config IOSCHED_CFQ
35config CFQ_GROUP_IOSCHED 36config CFQ_GROUP_IOSCHED
36 bool "CFQ Group Scheduling support" 37 bool "CFQ Group Scheduling support"
37 depends on IOSCHED_CFQ && CGROUPS 38 depends on IOSCHED_CFQ && CGROUPS
38 select BLK_CGROUP
39 default n 39 default n
40 ---help--- 40 ---help---
41 Enable group IO scheduling in CFQ. 41 Enable group IO scheduling in CFQ.
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index c85d74cae200..4b686ad08eaa 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -23,6 +23,31 @@ static LIST_HEAD(blkio_list);
23struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT }; 23struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT };
24EXPORT_SYMBOL_GPL(blkio_root_cgroup); 24EXPORT_SYMBOL_GPL(blkio_root_cgroup);
25 25
26static struct cgroup_subsys_state *blkiocg_create(struct cgroup_subsys *,
27 struct cgroup *);
28static int blkiocg_can_attach(struct cgroup_subsys *, struct cgroup *,
29 struct task_struct *, bool);
30static void blkiocg_attach(struct cgroup_subsys *, struct cgroup *,
31 struct cgroup *, struct task_struct *, bool);
32static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *);
33static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *);
34
35struct cgroup_subsys blkio_subsys = {
36 .name = "blkio",
37 .create = blkiocg_create,
38 .can_attach = blkiocg_can_attach,
39 .attach = blkiocg_attach,
40 .destroy = blkiocg_destroy,
41 .populate = blkiocg_populate,
42#ifdef CONFIG_BLK_CGROUP
43 /* note: blkio_subsys_id is otherwise defined in blk-cgroup.h */
44 .subsys_id = blkio_subsys_id,
45#endif
46 .use_id = 1,
47 .module = THIS_MODULE,
48};
49EXPORT_SYMBOL_GPL(blkio_subsys);
50
26struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup) 51struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
27{ 52{
28 return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id), 53 return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id),
@@ -253,7 +278,8 @@ remove_entry:
253done: 278done:
254 free_css_id(&blkio_subsys, &blkcg->css); 279 free_css_id(&blkio_subsys, &blkcg->css);
255 rcu_read_unlock(); 280 rcu_read_unlock();
256 kfree(blkcg); 281 if (blkcg != &blkio_root_cgroup)
282 kfree(blkcg);
257} 283}
258 284
259static struct cgroup_subsys_state * 285static struct cgroup_subsys_state *
@@ -319,17 +345,6 @@ static void blkiocg_attach(struct cgroup_subsys *subsys, struct cgroup *cgroup,
319 task_unlock(tsk); 345 task_unlock(tsk);
320} 346}
321 347
322struct cgroup_subsys blkio_subsys = {
323 .name = "blkio",
324 .create = blkiocg_create,
325 .can_attach = blkiocg_can_attach,
326 .attach = blkiocg_attach,
327 .destroy = blkiocg_destroy,
328 .populate = blkiocg_populate,
329 .subsys_id = blkio_subsys_id,
330 .use_id = 1,
331};
332
333void blkio_policy_register(struct blkio_policy_type *blkiop) 348void blkio_policy_register(struct blkio_policy_type *blkiop)
334{ 349{
335 spin_lock(&blkio_list_lock); 350 spin_lock(&blkio_list_lock);
@@ -345,3 +360,17 @@ void blkio_policy_unregister(struct blkio_policy_type *blkiop)
345 spin_unlock(&blkio_list_lock); 360 spin_unlock(&blkio_list_lock);
346} 361}
347EXPORT_SYMBOL_GPL(blkio_policy_unregister); 362EXPORT_SYMBOL_GPL(blkio_policy_unregister);
363
364static int __init init_cgroup_blkio(void)
365{
366 return cgroup_load_subsys(&blkio_subsys);
367}
368
369static void __exit exit_cgroup_blkio(void)
370{
371 cgroup_unload_subsys(&blkio_subsys);
372}
373
374module_init(init_cgroup_blkio);
375module_exit(exit_cgroup_blkio);
376MODULE_LICENSE("GPL");
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 84bf745fa775..8ccc20464dae 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -15,7 +15,13 @@
15 15
16#include <linux/cgroup.h> 16#include <linux/cgroup.h>
17 17
18#ifdef CONFIG_BLK_CGROUP 18#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
19
20#ifndef CONFIG_BLK_CGROUP
21/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */
22extern struct cgroup_subsys blkio_subsys;
23#define blkio_subsys_id blkio_subsys.subsys_id
24#endif
19 25
20struct blkio_cgroup { 26struct blkio_cgroup {
21 struct cgroup_subsys_state css; 27 struct cgroup_subsys_state css;
@@ -91,7 +97,7 @@ static inline void blkiocg_update_blkio_group_dequeue_stats(
91 struct blkio_group *blkg, unsigned long dequeue) {} 97 struct blkio_group *blkg, unsigned long dequeue) {}
92#endif 98#endif
93 99
94#ifdef CONFIG_BLK_CGROUP 100#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
95extern struct blkio_cgroup blkio_root_cgroup; 101extern struct blkio_cgroup blkio_root_cgroup;
96extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup); 102extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
97extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg, 103extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
diff --git a/include/linux/iocontext.h b/include/linux/iocontext.h
index 1195a806fe0c..a0bb301afac0 100644
--- a/include/linux/iocontext.h
+++ b/include/linux/iocontext.h
@@ -42,7 +42,7 @@ struct io_context {
42 unsigned short ioprio; 42 unsigned short ioprio;
43 unsigned short ioprio_changed; 43 unsigned short ioprio_changed;
44 44
45#ifdef CONFIG_BLK_CGROUP 45#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
46 unsigned short cgroup_changed; 46 unsigned short cgroup_changed;
47#endif 47#endif
48 48
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index aa889c96cc74..521591dbab2f 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -705,6 +705,7 @@ void cgroup_lock(void)
705{ 705{
706 mutex_lock(&cgroup_mutex); 706 mutex_lock(&cgroup_mutex);
707} 707}
708EXPORT_SYMBOL_GPL(cgroup_lock);
708 709
709/** 710/**
710 * cgroup_unlock - release lock on cgroup changes 711 * cgroup_unlock - release lock on cgroup changes
@@ -715,6 +716,7 @@ void cgroup_unlock(void)
715{ 716{
716 mutex_unlock(&cgroup_mutex); 717 mutex_unlock(&cgroup_mutex);
717} 718}
719EXPORT_SYMBOL_GPL(cgroup_unlock);
718 720
719/* 721/*
720 * A couple of forward declarations required, due to cyclic reference loop: 722 * A couple of forward declarations required, due to cyclic reference loop:
@@ -1639,6 +1641,7 @@ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
1639 memmove(buf, start, buf + buflen - start); 1641 memmove(buf, start, buf + buflen - start);
1640 return 0; 1642 return 0;
1641} 1643}
1644EXPORT_SYMBOL_GPL(cgroup_path);
1642 1645
1643/** 1646/**
1644 * cgroup_attach_task - attach task 'tsk' to cgroup 'cgrp' 1647 * cgroup_attach_task - attach task 'tsk' to cgroup 'cgrp'
@@ -1805,6 +1808,7 @@ bool cgroup_lock_live_group(struct cgroup *cgrp)
1805 } 1808 }
1806 return true; 1809 return true;
1807} 1810}
1811EXPORT_SYMBOL_GPL(cgroup_lock_live_group);
1808 1812
1809static int cgroup_release_agent_write(struct cgroup *cgrp, struct cftype *cft, 1813static int cgroup_release_agent_write(struct cgroup *cgrp, struct cftype *cft,
1810 const char *buffer) 1814 const char *buffer)
@@ -4082,6 +4086,7 @@ void __css_put(struct cgroup_subsys_state *css, int count)
4082 rcu_read_unlock(); 4086 rcu_read_unlock();
4083 WARN_ON_ONCE(val < 1); 4087 WARN_ON_ONCE(val < 1);
4084} 4088}
4089EXPORT_SYMBOL_GPL(__css_put);
4085 4090
4086/* 4091/*
4087 * Notify userspace when a cgroup is released, by running the 4092 * Notify userspace when a cgroup is released, by running the
@@ -4197,6 +4202,7 @@ unsigned short css_id(struct cgroup_subsys_state *css)
4197 return cssid->id; 4202 return cssid->id;
4198 return 0; 4203 return 0;
4199} 4204}
4205EXPORT_SYMBOL_GPL(css_id);
4200 4206
4201unsigned short css_depth(struct cgroup_subsys_state *css) 4207unsigned short css_depth(struct cgroup_subsys_state *css)
4202{ 4208{
@@ -4206,6 +4212,7 @@ unsigned short css_depth(struct cgroup_subsys_state *css)
4206 return cssid->depth; 4212 return cssid->depth;
4207 return 0; 4213 return 0;
4208} 4214}
4215EXPORT_SYMBOL_GPL(css_depth);
4209 4216
4210bool css_is_ancestor(struct cgroup_subsys_state *child, 4217bool css_is_ancestor(struct cgroup_subsys_state *child,
4211 const struct cgroup_subsys_state *root) 4218 const struct cgroup_subsys_state *root)
@@ -4242,6 +4249,7 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
4242 spin_unlock(&ss->id_lock); 4249 spin_unlock(&ss->id_lock);
4243 call_rcu(&id->rcu_head, __free_css_id_cb); 4250 call_rcu(&id->rcu_head, __free_css_id_cb);
4244} 4251}
4252EXPORT_SYMBOL_GPL(free_css_id);
4245 4253
4246/* 4254/*
4247 * This is called by init or create(). Then, calls to this function are 4255 * This is called by init or create(). Then, calls to this function are
@@ -4358,6 +4366,7 @@ struct cgroup_subsys_state *css_lookup(struct cgroup_subsys *ss, int id)
4358 4366
4359 return rcu_dereference(cssid->css); 4367 return rcu_dereference(cssid->css);
4360} 4368}
4369EXPORT_SYMBOL_GPL(css_lookup);
4361 4370
4362/** 4371/**
4363 * css_get_next - lookup next cgroup under specified hierarchy. 4372 * css_get_next - lookup next cgroup under specified hierarchy.