cgroup: Move debug cgroup to its own file

The debug cgroup currently resides within cgroup-v1.c and is enabled
only for v1 cgroup. To enable the debug cgroup also for v2, it makes
sense to put the code into its own file as it will no longer be v1
specific. There is no change to the debug cgroup specific code.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile
index 387348a40c647ba8f9ee4e34ba1f363a9449a458..ce693ccb8c58fa4f5be8532790ab8b0ca50a3b9a 100644 (file)
--- a/kernel/cgroup/Makefile
+++ b/kernel/cgroup/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_CGROUP_FREEZER) += freezer.o
 obj-$(CONFIG_CGROUP_PIDS) += pids.o
 obj-$(CONFIG_CGROUP_RDMA) += rdma.o
 obj-$(CONFIG_CPUSETS) += cpuset.o
+obj-$(CONFIG_CGROUP_DEBUG) += debug.o

diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index 00f4d6bf048fab1d25068842859075a3e3b952dd..793565c057426656312ab7b31471f6c523b7ae59 100644 (file)
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -192,6 +192,8 @@ int cgroup_rmdir(struct kernfs_node *kn);
 int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node,
                     struct kernfs_root *kf_root);
 
+int cgroup_task_count(const struct cgroup *cgrp);
+
 /*
  * namespace.c
  */

diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index e9ea5f201fac9539ad9f4eae1511b5fd991f434d..7bf4b1533f3466411fecaaab4e761f12323a3810 100644 (file)
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -335,7 +335,7 @@ static struct cgroup_pidlist *cgroup_pidlist_find_create(struct cgroup *cgrp,
  * cgroup_task_count - count the number of tasks in a cgroup.
  * @cgrp: the cgroup in question
  */
-static int cgroup_task_count(const struct cgroup *cgrp)
+int cgroup_task_count(const struct cgroup *cgrp)
 {
        int count = 0;
        struct cgrp_cset_link *link;
@@ -1259,150 +1259,3 @@ static int __init cgroup_no_v1(char *str)
        return 1;
 }
 __setup("cgroup_no_v1=", cgroup_no_v1);
-
-
-#ifdef CONFIG_CGROUP_DEBUG
-static struct cgroup_subsys_state *
-debug_css_alloc(struct cgroup_subsys_state *parent_css)
-{
-       struct cgroup_subsys_state *css = kzalloc(sizeof(*css), GFP_KERNEL);
-
-       if (!css)
-               return ERR_PTR(-ENOMEM);
-
-       return css;
-}
-
-static void debug_css_free(struct cgroup_subsys_state *css)
-{
-       kfree(css);
-}
-
-static u64 debug_taskcount_read(struct cgroup_subsys_state *css,
-                               struct cftype *cft)
-{
-       return cgroup_task_count(css->cgroup);
-}
-
-static u64 current_css_set_read(struct cgroup_subsys_state *css,
-                               struct cftype *cft)
-{
-       return (u64)(unsigned long)current->cgroups;
-}
-
-static u64 current_css_set_refcount_read(struct cgroup_subsys_state *css,
-                                        struct cftype *cft)
-{
-       u64 count;
-
-       rcu_read_lock();
-       count = refcount_read(&task_css_set(current)->refcount);
-       rcu_read_unlock();
-       return count;
-}
-
-static int current_css_set_cg_links_read(struct seq_file *seq, void *v)
-{
-       struct cgrp_cset_link *link;
-       struct css_set *cset;
-       char *name_buf;
-
-       name_buf = kmalloc(NAME_MAX + 1, GFP_KERNEL);
-       if (!name_buf)
-               return -ENOMEM;
-
-       spin_lock_irq(&css_set_lock);
-       rcu_read_lock();
-       cset = rcu_dereference(current->cgroups);
-       list_for_each_entry(link, &cset->cgrp_links, cgrp_link) {
-               struct cgroup *c = link->cgrp;
-
-               cgroup_name(c, name_buf, NAME_MAX + 1);
-               seq_printf(seq, "Root %d group %s\n",
-                          c->root->hierarchy_id, name_buf);
-       }
-       rcu_read_unlock();
-       spin_unlock_irq(&css_set_lock);
-       kfree(name_buf);
-       return 0;
-}
-
-#define MAX_TASKS_SHOWN_PER_CSS 25
-static int cgroup_css_links_read(struct seq_file *seq, void *v)
-{
-       struct cgroup_subsys_state *css = seq_css(seq);
-       struct cgrp_cset_link *link;
-
-       spin_lock_irq(&css_set_lock);
-       list_for_each_entry(link, &css->cgroup->cset_links, cset_link) {
-               struct css_set *cset = link->cset;
-               struct task_struct *task;
-               int count = 0;
-
-               seq_printf(seq, "css_set %pK\n", cset);
-
-               list_for_each_entry(task, &cset->tasks, cg_list) {
-                       if (count++ > MAX_TASKS_SHOWN_PER_CSS)
-                               goto overflow;
-                       seq_printf(seq, "  task %d\n", task_pid_vnr(task));
-               }
-
-               list_for_each_entry(task, &cset->mg_tasks, cg_list) {
-                       if (count++ > MAX_TASKS_SHOWN_PER_CSS)
-                               goto overflow;
-                       seq_printf(seq, "  task %d\n", task_pid_vnr(task));
-               }
-               continue;
-       overflow:
-               seq_puts(seq, "  ...\n");
-       }
-       spin_unlock_irq(&css_set_lock);
-       return 0;
-}
-
-static u64 releasable_read(struct cgroup_subsys_state *css, struct cftype *cft)
-{
-       return (!cgroup_is_populated(css->cgroup) &&
-               !css_has_online_children(&css->cgroup->self));
-}
-
-static struct cftype debug_files[] =  {
-       {
-               .name = "taskcount",
-               .read_u64 = debug_taskcount_read,
-       },
-
-       {
-               .name = "current_css_set",
-               .read_u64 = current_css_set_read,
-       },
-
-       {
-               .name = "current_css_set_refcount",
-               .read_u64 = current_css_set_refcount_read,
-       },
-
-       {
-               .name = "current_css_set_cg_links",
-               .seq_show = current_css_set_cg_links_read,
-       },
-
-       {
-               .name = "cgroup_css_links",
-               .seq_show = cgroup_css_links_read,
-       },
-
-       {
-               .name = "releasable",
-               .read_u64 = releasable_read,
-       },
-
-       { }     /* terminate */
-};
-
-struct cgroup_subsys debug_cgrp_subsys = {
-       .css_alloc = debug_css_alloc,
-       .css_free = debug_css_free,
-       .legacy_cftypes = debug_files,
-};
-#endif /* CONFIG_CGROUP_DEBUG */

diff --git a/kernel/cgroup/debug.c b/kernel/cgroup/debug.c
new file mode 100644 (file)
index 0000000..1c209aa
--- /dev/null
+++ b/kernel/cgroup/debug.c
@@ -0,0 +1,153 @@
+#include <linux/ctype.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+
+#include "cgroup-internal.h"
+
+static struct cgroup_subsys_state *
+debug_css_alloc(struct cgroup_subsys_state *parent_css)
+{
+       struct cgroup_subsys_state *css = kzalloc(sizeof(*css), GFP_KERNEL);
+
+       if (!css)
+               return ERR_PTR(-ENOMEM);
+
+       return css;
+}
+
+static void debug_css_free(struct cgroup_subsys_state *css)
+{
+       kfree(css);
+}
+
+/*
+ * debug_taskcount_read - return the number of tasks in a cgroup.
+ * @cgrp: the cgroup in question
+ */
+static u64 debug_taskcount_read(struct cgroup_subsys_state *css,
+                               struct cftype *cft)
+{
+       return cgroup_task_count(css->cgroup);
+}
+
+static u64 current_css_set_read(struct cgroup_subsys_state *css,
+                               struct cftype *cft)
+{
+       return (u64)(unsigned long)current->cgroups;
+}
+
+static u64 current_css_set_refcount_read(struct cgroup_subsys_state *css,
+                                        struct cftype *cft)
+{
+       u64 count;
+
+       rcu_read_lock();
+       count = refcount_read(&task_css_set(current)->refcount);
+       rcu_read_unlock();
+       return count;
+}
+
+static int current_css_set_cg_links_read(struct seq_file *seq, void *v)
+{
+       struct cgrp_cset_link *link;
+       struct css_set *cset;
+       char *name_buf;
+
+       name_buf = kmalloc(NAME_MAX + 1, GFP_KERNEL);
+       if (!name_buf)
+               return -ENOMEM;
+
+       spin_lock_irq(&css_set_lock);
+       rcu_read_lock();
+       cset = rcu_dereference(current->cgroups);
+       list_for_each_entry(link, &cset->cgrp_links, cgrp_link) {
+               struct cgroup *c = link->cgrp;
+
+               cgroup_name(c, name_buf, NAME_MAX + 1);
+               seq_printf(seq, "Root %d group %s\n",
+                          c->root->hierarchy_id, name_buf);
+       }
+       rcu_read_unlock();
+       spin_unlock_irq(&css_set_lock);
+       kfree(name_buf);
+       return 0;
+}
+
+#define MAX_TASKS_SHOWN_PER_CSS 25
+static int cgroup_css_links_read(struct seq_file *seq, void *v)
+{
+       struct cgroup_subsys_state *css = seq_css(seq);
+       struct cgrp_cset_link *link;
+
+       spin_lock_irq(&css_set_lock);
+       list_for_each_entry(link, &css->cgroup->cset_links, cset_link) {
+               struct css_set *cset = link->cset;
+               struct task_struct *task;
+               int count = 0;
+
+               seq_printf(seq, "css_set %pK\n", cset);
+
+               list_for_each_entry(task, &cset->tasks, cg_list) {
+                       if (count++ > MAX_TASKS_SHOWN_PER_CSS)
+                               goto overflow;
+                       seq_printf(seq, "  task %d\n", task_pid_vnr(task));
+               }
+
+               list_for_each_entry(task, &cset->mg_tasks, cg_list) {
+                       if (count++ > MAX_TASKS_SHOWN_PER_CSS)
+                               goto overflow;
+                       seq_printf(seq, "  task %d\n", task_pid_vnr(task));
+               }
+               continue;
+       overflow:
+               seq_puts(seq, "  ...\n");
+       }
+       spin_unlock_irq(&css_set_lock);
+       return 0;
+}
+
+static u64 releasable_read(struct cgroup_subsys_state *css, struct cftype *cft)
+{
+       return (!cgroup_is_populated(css->cgroup) &&
+               !css_has_online_children(&css->cgroup->self));
+}
+
+static struct cftype debug_files[] =  {
+       {
+               .name = "taskcount",
+               .read_u64 = debug_taskcount_read,
+       },
+
+       {
+               .name = "current_css_set",
+               .read_u64 = current_css_set_read,
+       },
+
+       {
+               .name = "current_css_set_refcount",
+               .read_u64 = current_css_set_refcount_read,
+       },
+
+       {
+               .name = "current_css_set_cg_links",
+               .seq_show = current_css_set_cg_links_read,
+       },
+
+       {
+               .name = "cgroup_css_links",
+               .seq_show = cgroup_css_links_read,
+       },
+
+       {
+               .name = "releasable",
+               .read_u64 = releasable_read,
+       },
+
+       { }     /* terminate */
+};
+
+struct cgroup_subsys debug_cgrp_subsys = {
+       .css_alloc = debug_css_alloc,
+       .css_free = debug_css_free,
+       .legacy_cftypes = debug_files,
+};