Task Control Groups: make cpusets a client of cgroups

Remove the filesystem support logic from the cpusets system and makes cpusets
a cgroup subsystem

The "cpuset" filesystem becomes a dummy filesystem; attempts to mount it get
passed through to the cgroup filesystem with the appropriate options to
emulate the old cpuset filesystem behaviour.

Signed-off-by: Paul Menage <menage@google.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 14 insertions, 19 deletions

diff --git a/include/linux/cgroup_subsys.h b/include/linux/cgroup_subsys.h
index f8eddbbcad9a..b152b51a4367 100644
--- a/include/linux/cgroup_subsys.h
+++ b/include/linux/cgroup_subsys.h
@@ -7,4 +7,10 @@
 
 /* */
 
+#ifdef CONFIG_CPUSETS
+SUBSYS(cpuset)
+#endif
+
+/* */
+
 /* */
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index ea44d2e768a0..31adfde1c95f 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -11,6 +11,7 @@
 #include <linux/sched.h>
 #include <linux/cpumask.h>
 #include <linux/nodemask.h>
+#include <linux/cgroup.h>
 
 #ifdef CONFIG_CPUSETS
 
@@ -19,8 +20,6 @@ extern int number_of_cpusets;	/* How many cpusets are defined in system? */
 extern int cpuset_init_early(void);
 extern int cpuset_init(void);
 extern void cpuset_init_smp(void);
-extern void cpuset_fork(struct task_struct *p);
-extern void cpuset_exit(struct task_struct *p);
 extern cpumask_t cpuset_cpus_allowed(struct task_struct *p);
 extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
 #define cpuset_current_mems_allowed (current->mems_allowed)
@@ -76,13 +75,13 @@ static inline int cpuset_do_slab_mem_spread(void)
 
 extern void cpuset_track_online_nodes(void);
 
+extern int current_cpuset_is_being_rebound(void);
+
 #else /* !CONFIG_CPUSETS */
 
 static inline int cpuset_init_early(void) { return 0; }
 static inline int cpuset_init(void) { return 0; }
 static inline void cpuset_init_smp(void) {}
-static inline void cpuset_fork(struct task_struct *p) {}
-static inline void cpuset_exit(struct task_struct *p) {}
 
 static inline cpumask_t cpuset_cpus_allowed(struct task_struct *p)
 {
@@ -148,6 +147,11 @@ static inline int cpuset_do_slab_mem_spread(void)
 
 static inline void cpuset_track_online_nodes(void) {}
 
+static inline int current_cpuset_is_being_rebound(void)
+{
+        return 0;
+}
+
 #endif /* !CONFIG_CPUSETS */
 
 #endif /* _LINUX_CPUSET_H */
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index 38c04d61ee06..59c4865bc85f 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -148,14 +148,6 @@ extern void mpol_rebind_task(struct task_struct *tsk,
                                         const nodemask_t *new);
 extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new);
 extern void mpol_fix_fork_child_flag(struct task_struct *p);
-#define set_cpuset_being_rebound(x) (cpuset_being_rebound = (x))
-
-#ifdef CONFIG_CPUSETS
-#define current_cpuset_is_being_rebound() \
-                                (cpuset_being_rebound == current->cpuset)
-#else
-#define current_cpuset_is_being_rebound() 0
-#endif
 
 extern struct mempolicy default_policy;
 extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
@@ -173,8 +165,6 @@ static inline void check_highest_zone(enum zone_type k)
 int do_migrate_pages(struct mm_struct *mm,
         const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags);
 
-extern void *cpuset_being_rebound;      /* Trigger mpol_copy vma rebind */
-
 #else
 
 struct mempolicy {};
@@ -248,8 +238,6 @@ static inline void mpol_fix_fork_child_flag(struct task_struct *p)
 {
 }
 
-#define set_cpuset_being_rebound(x) do {} while (0)
-
 static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
                 unsigned long addr, gfp_t gfp_flags, struct mempolicy **mpol)
 {
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 1aa1cfa63b37..93a55f2e5ef6 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -756,8 +756,6 @@ static inline int above_background_load(void)
 }
 
 struct io_context;                      /* See blkdev.h */
-struct cpuset;
-
 #define NGROUPS_SMALL           32
 #define NGROUPS_PER_BLOCK       ((int)(PAGE_SIZE / sizeof(gid_t)))
 struct group_info {
@@ -1125,7 +1123,6 @@ struct task_struct {
         short il_next;
 #endif
 #ifdef CONFIG_CPUSETS
-        struct cpuset *cpuset;
         nodemask_t mems_allowed;
         int cpuset_mems_generation;
         int cpuset_mem_spread_rotor;