Merge branch 'for-3.5' of ../cgroup into block/for-3.5/core-merged

cgroup/for-3.5 contains the following changes which blk-cgroup needs
to proceed with the on-going cleanup.

* Dynamic addition and removal of cftypes to make config/stat file
  handling modular for policies.

* cgroup removal update to not wait for css references to drain to fix
  blkcg removal hang caused by cfq caching cfqgs.

Pull in cgroup/for-3.5 into block/for-3.5/core.  This causes the
following conflicts in block/blk-cgroup.c.

* 761b3ef50e "cgroup: remove cgroup_subsys argument from callbacks"
  conflicts with blkiocg_pre_destroy() addition and blkiocg_attach()
  removal.  Resolved by removing @subsys from all subsys methods.

* 676f7c8f84 "cgroup: relocate cftype and cgroup_subsys definitions in
  controllers" conflicts with ->pre_destroy() and ->attach() updates
  and removal of modular config.  Resolved by dropping forward
  declarations of the methods and applying updates to the relocated
  blkio_subsys.

* 4baf6e3325 "cgroup: convert all non-memcg controllers to the new
  cftype interface" builds upon the previous item.  Resolved by adding
  ->base_cftypes to the relocated blkio_subsys.

Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 17 insertions, 34 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index aa54c4110f54..4fdeb46b4436 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -43,32 +43,12 @@ EXPORT_SYMBOL_GPL(blkio_root_cgroup);
 
 static struct blkio_policy_type *blkio_policy[BLKIO_NR_POLICIES];
 
-static struct cgroup_subsys_state *blkiocg_create(struct cgroup_subsys *,
-                                                  struct cgroup *);
-static int blkiocg_can_attach(struct cgroup_subsys *, struct cgroup *,
-                              struct cgroup_taskset *);
-static int blkiocg_pre_destroy(struct cgroup_subsys *, struct cgroup *);
-static void blkiocg_destroy(struct cgroup_subsys *, struct cgroup *);
-static int blkiocg_populate(struct cgroup_subsys *, struct cgroup *);
-
 /* for encoding cft->private value on file */
 #define BLKIOFILE_PRIVATE(x, val)       (((x) << 16) | (val))
 /* What policy owns the file, proportional or throttle */
 #define BLKIOFILE_POLICY(val)           (((val) >> 16) & 0xffff)
 #define BLKIOFILE_ATTR(val)             ((val) & 0xffff)
 
-struct cgroup_subsys blkio_subsys = {
-        .name = "blkio",
-        .create = blkiocg_create,
-        .can_attach = blkiocg_can_attach,
-        .pre_destroy = blkiocg_pre_destroy,
-        .destroy = blkiocg_destroy,
-        .populate = blkiocg_populate,
-        .subsys_id = blkio_subsys_id,
-        .module = THIS_MODULE,
-};
-EXPORT_SYMBOL_GPL(blkio_subsys);
-
 struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup)
 {
         return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id),
@@ -1563,17 +1543,11 @@ struct cftype blkio_files[] = {
                 .read_map = blkiocg_file_read_map,
         },
 #endif
+        { }     /* terminate */
 };
 
-static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup)
-{
-        return cgroup_add_files(cgroup, subsys, blkio_files,
-                                ARRAY_SIZE(blkio_files));
-}
-
 /**
  * blkiocg_pre_destroy - cgroup pre_destroy callback
- * @subsys: cgroup subsys
  * @cgroup: cgroup of interest
  *
  * This function is called when @cgroup is about to go away and responsible
@@ -1583,8 +1557,7 @@ static int blkiocg_populate(struct cgroup_subsys *subsys, struct cgroup *cgroup)
  *
  * This is the blkcg counterpart of ioc_release_fn().
  */
-static int blkiocg_pre_destroy(struct cgroup_subsys *subsys,
-                               struct cgroup *cgroup)
+static int blkiocg_pre_destroy(struct cgroup *cgroup)
 {
         struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
 
@@ -1609,7 +1582,7 @@ static int blkiocg_pre_destroy(struct cgroup_subsys *subsys,
         return 0;
 }
 
-static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup)
+static void blkiocg_destroy(struct cgroup *cgroup)
 {
         struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
 
@@ -1617,8 +1590,7 @@ static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup)
                 kfree(blkcg);
 }
 
-static struct cgroup_subsys_state *
-blkiocg_create(struct cgroup_subsys *subsys, struct cgroup *cgroup)
+static struct cgroup_subsys_state *blkiocg_create(struct cgroup *cgroup)
 {
         static atomic64_t id_seq = ATOMIC64_INIT(0);
         struct blkio_cgroup *blkcg;
@@ -1706,8 +1678,7 @@ void blkcg_exit_queue(struct request_queue *q)
  * of the main cic data structures.  For now we allow a task to change
  * its cgroup only if it's the only owner of its ioc.
  */
-static int blkiocg_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
-                              struct cgroup_taskset *tset)
+static int blkiocg_can_attach(struct cgroup *cgrp, struct cgroup_taskset *tset)
 {
         struct task_struct *task;
         struct io_context *ioc;
@@ -1750,6 +1721,18 @@ static void blkcg_bypass_end(void)
         mutex_unlock(&all_q_mutex);
 }
 
+struct cgroup_subsys blkio_subsys = {
+        .name = "blkio",
+        .create = blkiocg_create,
+        .can_attach = blkiocg_can_attach,
+        .pre_destroy = blkiocg_pre_destroy,
+        .destroy = blkiocg_destroy,
+        .subsys_id = blkio_subsys_id,
+        .base_cftypes = blkio_files,
+        .module = THIS_MODULE,
+};
+EXPORT_SYMBOL_GPL(blkio_subsys);
+
 void blkio_policy_register(struct blkio_policy_type *blkiop)
 {
         struct request_queue *q;