[PATCH 05/12] Init and clear resource group info in task

Chandra Seetharaman
2006-04-28T01:44:11Z

05/12 - tasksupport_fork_exit_init

Initializes and clears Resource Group specific information in a task at
fork() and exit().
Inititalizes Resource Groups (called from start_kernel)
--

Signed-Off-By: Chandra Seetharaman <sekharan@us.ibm.com>

include/linux/res_group.h | 7 +++++
init/main.c | 2 +
kernel/exit.c | 2 +
kernel/fork.c | 2 +
kernel/res_group/local.h | 1
kernel/res_group/res_group.c | 11 +++++++++
kernel/res_group/task.c | 52 +++++++++++++++++++++++++++++++++++++++++++
7 files changed, 77 insertions(+)

Index: linux-2617-rc3/kernel/exit.c
===================================================================
--- linux-2617-rc3.orig/kernel/exit.c 2006-04-27 09:18:03.000000000 -0700
+++ linux-2617-rc3/kernel/exit.c 2006-04-27 09:22:20.000000000 -0700
@@ -35,6 +35,7 @@
#include <linux/futex.h>
#include <linux/compat.h>
#include <linux/pipe_fs_i.h>
+#include <linux/res_group.h>

#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -731,6 +732,7 @@ static void exit_notify(struct task_stru
struct task_struct *t;
struct list_head ptrace_dead, *_p, *_n;

+ clear_task_res_group(tsk);
if (signal_pending(tsk) && !(tsk->signal->flags & SIGNAL_GROUP_EXIT)
&& !thread_group_empty(tsk)) {
/*
Index: linux-2617-rc3/kernel/fork.c
===================================================================
--- linux-2617-rc3.orig/kernel/fork.c 2006-04-27 09:18:03.000000000 -0700
+++ linux-2617-rc3/kernel/fork.c 2006-04-27 09:22:20.000000000 -0700
@@ -44,6 +44,7 @@
#include <linux/rmap.h>
#include <linux/acct.h>
#include <linux/cn_proc.h>
+#include <linux/res_group.h>

#include <asm/pgtable.h>
#include <asm/pgalloc.h>
@@ -1215,6 +1216,7 @@ static task_t *copy_process(unsigned lon
total_forks++;
spin_unlock(&current->sighand->siglock);
write_unlock_irq(&tasklist_lock);
+ init_task_res_group(p);
proc_fork_connector(p);
return p;

Index: linux-2617-rc3/init/main.c
===================================================================
--- linux-2617-rc3.orig/init/main.c 2006-04-27 09:18:03.000000000 -0700
+++ linux-2617-rc3/init/main.c 2006-04-27 09:22:20.000000000 -0700
@@ -47,6 +47,7 @@
#include <linux/rmap.h>
#include <linux/mempolicy.h>
#include <linux/key.h>
+#include <linux/res_group.h>

#include <asm/io.h>
#include <asm/bugs.h>
@@ -541,6 +542,7 @@ asmlinkage void __init start_kernel(void
proc_root_init();
#endif
cpuset_init();
+ res_group_init();

check_bugs();

Index: linux-2617-rc3/kernel/res_group/res_group.c
===================================================================
--- linux-2617-rc3.orig/kernel/res_group/res_group.c 2006-04-27 09:22:16.000000000 -0700
+++ linux-2617-rc3/kernel/res_group/res_group.c 2006-04-27 09:22:20.000000000 -0700
@@ -231,6 +231,7 @@ int free_res_group(struct resource_group
return -EBUSY;
}
spin_unlock(&rgroup->group_lock);
+ move_tasks_to_parent(rgroup);
kref_put(&rgroup->ref, release_res_group);
return 0;
}
@@ -392,6 +393,16 @@ void res_group_teardown(void)
}
}

+void res_group_init(void)
+{
+ write_lock(&res_group_lock);
+ list_add_tail(&default_res_group.group_list, &res_groups);
+ write_unlock(&res_group_lock);
+ kref_init(&default_res_group.ref);
+ init_task.res_group = &default_res_group;
+ init_task_res_group(&init_task);
+}
+
EXPORT_SYMBOL_GPL(register_controller);
EXPORT_SYMBOL_GPL(unregister_controller);
EXPORT_SYMBOL_GPL(get_controller_by_name);
Index: linux-2617-rc3/kernel/res_group/task.c
===================================================================
--- linux-2617-rc3.orig/kernel/res_group/task.c 2006-04-27 09:22:16.000000000 -0700
+++ linux-2617-rc3/kernel/res_group/task.c 2006-04-27 09:22:20.000000000 -0700
@@ -142,4 +142,56 @@ int set_res_group(pid_t pid, struct reso
put_task_struct(tsk);
return rc;
}
+
+void init_task_res_group(struct task_struct *tsk)
+{
+ struct resource_group *rgroup;
+
+ /*
+ * processes inherit their resource group from their real parent and
+ * threads inherit resource group from their process.
+ */
+ if (thread_group_leader(tsk))
+ rgroup = tsk->real_parent->res_group;
+ else
+ rgroup = tsk->group_leader->res_group;
+
+ tsk->res_group = NO_RES_GROUP;
+ INIT_LIST_HEAD(&tsk->member_list);
+
+ BUG_ON(rgroup == NULL);
+ kref_get(&rgroup->ref);
+ move_to_new_rgroup(tsk, rgroup);
+ notify_res_ctlrs(tsk, NO_RES_GROUP, rgroup);
+}
+
+void clear_task_res_group(struct task_struct *tsk)
+{
+ __set_res_group(tsk, NO_RES_GROUP);
+}
+
+/*
+ * Move all tasks in the given resource group to its parent.
+ */
+void move_tasks_to_parent(struct resource_group *rgroup)
+{
+ kref_get(&rgroup->ref);
+
+next_task:
+ spin_lock(&rgroup->group_lock);
+ if (!list_empty(&rgroup->task_list)) {
+ struct task_struct *tsk =
+ list_entry(rgroup->task_list.next,
+ struct task_struct, member_list);
+ get_task_struct(tsk);
+ spin_unlock(&rgroup->group_lock);
+ kref_get(&rgroup->parent->ref);
+ __set_res_group(tsk, rgroup->parent);
+ put_task_struct(tsk);
+ goto next_task;
+ }
+ spin_unlock(&rgroup->group_lock);
+ kref_put(&rgroup->ref, release_res_group);
+}
+
EXPORT_SYMBOL_GPL(set_res_group);
Index: linux-2617-rc3/include/linux/res_group.h
===================================================================
--- linux-2617-rc3.orig/include/linux/res_group.h 2006-04-27 09:22:07.000000000 -0700
+++ linux-2617-rc3/include/linux/res_group.h 2006-04-27 09:22:20.000000000 -0700
@@ -94,5 +94,12 @@ struct resource_group {
struct list_head children; /* head of children */
};

+extern void init_task_res_group(struct task_struct *);
+extern void clear_task_res_group(struct task_struct *);
+extern void res_group_init(void);
+#else /* CONFIG_RES_GROUPS */
+static inline void init_task_res_group(struct task_struct *tsk) { }
+static inline void clear_task_res_group(struct task_struct *tsk) { }
+static inline void res_group_init(void) { }
#endif /* CONFIG_RES_GROUPS */
#endif /* _LINUX_RES_GROUP_H */
Index: linux-2617-rc3/kernel/res_group/local.h
===================================================================
--- linux-2617-rc3.orig/kernel/res_group/local.h 2006-04-27 09:22:16.000000000 -0700
+++ linux-2617-rc3/kernel/res_group/local.h 2006-04-27 09:22:20.000000000 -0700
@@ -19,3 +19,4 @@ extern void set_shares_to_default(struct
struct res_controller *);
extern void res_group_teardown(void);
extern int set_res_group(pid_t, struct resource_group *);
+extern void move_tasks_to_parent(struct resource_group *);