Release 4.17 kernel/cgroup/debug.c
// SPDX-License-Identifier: GPL-2.0
/*
* Debug controller
*
* WARNING: This controller is for cgroup core debugging only.
* Its interfaces are unstable and subject to changes at any time.
*/
#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;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 44 | 100.00% | 1 | 100.00% |
| Total | 44 | 100.00% | 1 | 100.00% |
static void debug_css_free(struct cgroup_subsys_state *css)
{
kfree(css);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 16 | 100.00% | 1 | 100.00% |
| Total | 16 | 100.00% | 1 | 100.00% |
/*
* 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);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 24 | 100.00% | 1 | 100.00% |
| Total | 24 | 100.00% | 1 | 100.00% |
static int current_css_set_read(struct seq_file *seq, void *v)
{
struct kernfs_open_file *of = seq->private;
struct css_set *cset;
struct cgroup_subsys *ss;
struct cgroup_subsys_state *css;
int i, refcnt;
if (!cgroup_kn_lock_live(of->kn, false))
return -ENODEV;
spin_lock_irq(&css_set_lock);
rcu_read_lock();
cset = task_css_set(current);
refcnt = refcount_read(&cset->refcount);
seq_printf(seq, "css_set %pK %d", cset, refcnt);
if (refcnt > cset->nr_tasks)
seq_printf(seq, " +%d", refcnt - cset->nr_tasks);
seq_puts(seq, "\n");
/*
* Print the css'es stored in the current css_set.
*/
for_each_subsys(ss, i) {
css = cset->subsys[ss->id];
if (!css)
continue;
seq_printf(seq, "%2d: %-4s\t- %lx[%d]\n", ss->id, ss->name,
(unsigned long)css, css->id);
}
rcu_read_unlock();
spin_unlock_irq(&css_set_lock);
cgroup_kn_unlock(of->kn);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 167 | 85.64% | 2 | 50.00% |
| Tejun Heo | 27 | 13.85% | 1 | 25.00% |
| Wang Long | 1 | 0.51% | 1 | 25.00% |
| Total | 195 | 100.00% | 4 | 100.00% |
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;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 41 | 100.00% | 1 | 100.00% |
| Total | 41 | 100.00% | 1 | 100.00% |
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 = task_css_set(current);
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;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 126 | 99.21% | 1 | 50.00% |
| Wang Long | 1 | 0.79% | 1 | 50.00% |
| Total | 127 | 100.00% | 2 | 100.00% |
#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;
int dead_cnt = 0, extra_refs = 0, threaded_csets = 0;
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;
int refcnt = refcount_read(&cset->refcount);
/*
* Print out the proc_cset and threaded_cset relationship
* and highlight difference between refcount and task_count.
*/
seq_printf(seq, "css_set %pK", cset);
if (rcu_dereference_protected(cset->dom_cset, 1) != cset) {
threaded_csets++;
seq_printf(seq, "=>%pK", cset->dom_cset);
}
if (!list_empty(&cset->threaded_csets)) {
struct css_set *tcset;
int idx = 0;
list_for_each_entry(tcset, &cset->threaded_csets,
threaded_csets_node) {
seq_puts(seq, idx ? "," : "<=");
seq_printf(seq, "%pK", tcset);
idx++;
}
} else {
seq_printf(seq, " %d", refcnt);
if (refcnt - cset->nr_tasks > 0) {
int extra = refcnt - cset->nr_tasks;
seq_printf(seq, " +%d", extra);
/*
* Take out the one additional reference in
* init_css_set.
*/
if (cset == &init_css_set)
extra--;
extra_refs += extra;
}
}
seq_puts(seq, "\n");
list_for_each_entry(task, &cset->tasks, cg_list) {
if (count++ <= MAX_TASKS_SHOWN_PER_CSS)
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)
seq_printf(seq, " task %d\n",
task_pid_vnr(task));
}
/* show # of overflowed tasks */
if (count > MAX_TASKS_SHOWN_PER_CSS)
seq_printf(seq, " ... (%d)\n",
count - MAX_TASKS_SHOWN_PER_CSS);
if (cset->dead) {
seq_puts(seq, " [dead]\n");
dead_cnt++;
}
WARN_ON(count != cset->nr_tasks);
}
spin_unlock_irq(&css_set_lock);
if (!dead_cnt && !extra_refs && !threaded_csets)
return 0;
seq_puts(seq, "\n");
if (threaded_csets)
seq_printf(seq, "threaded css_sets = %d\n", threaded_csets);
if (extra_refs)
seq_printf(seq, "extra references = %d\n", extra_refs);
if (dead_cnt)
seq_printf(seq, "dead css_sets = %d\n", dead_cnt);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 420 | 100.00% | 3 | 100.00% |
| Total | 420 | 100.00% | 3 | 100.00% |
static int cgroup_subsys_states_read(struct seq_file *seq, void *v)
{
struct kernfs_open_file *of = seq->private;
struct cgroup *cgrp;
struct cgroup_subsys *ss;
struct cgroup_subsys_state *css;
char pbuf[16];
int i;
cgrp = cgroup_kn_lock_live(of->kn, false);
if (!cgrp)
return -ENODEV;
for_each_subsys(ss, i) {
css = rcu_dereference_check(cgrp->subsys[ss->id], true);
if (!css)
continue;
pbuf[0] = '\0';
/* Show the parent CSS if applicable*/
if (css->parent)
snprintf(pbuf, sizeof(pbuf) - 1, " P=%d",
css->parent->id);
seq_printf(seq, "%2d: %-4s\t- %lx[%d] %d%s\n", ss->id, ss->name,
(unsigned long)css, css->id,
atomic_read(&css->online_cnt), pbuf);
}
cgroup_kn_unlock(of->kn);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 149 | 84.18% | 1 | 50.00% |
| Tejun Heo | 28 | 15.82% | 1 | 50.00% |
| Total | 177 | 100.00% | 2 | 100.00% |
static void cgroup_masks_read_one(struct seq_file *seq, const char *name,
u16 mask)
{
struct cgroup_subsys *ss;
int ssid;
bool first = true;
seq_printf(seq, "%-17s: ", name);
for_each_subsys(ss, ssid) {
if (!(mask & (1 << ssid)))
continue;
if (!first)
seq_puts(seq, ", ");
seq_puts(seq, ss->name);
first = false;
}
seq_putc(seq, '\n');
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 84 | 88.42% | 1 | 50.00% |
| Tejun Heo | 11 | 11.58% | 1 | 50.00% |
| Total | 95 | 100.00% | 2 | 100.00% |
static int cgroup_masks_read(struct seq_file *seq, void *v)
{
struct kernfs_open_file *of = seq->private;
struct cgroup *cgrp;
cgrp = cgroup_kn_lock_live(of->kn, false);
if (!cgrp)
return -ENODEV;
cgroup_masks_read_one(seq, "subtree_control", cgrp->subtree_control);
cgroup_masks_read_one(seq, "subtree_ss_mask", cgrp->subtree_ss_mask);
cgroup_kn_unlock(of->kn);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Tejun Heo | 74 | 91.36% | 2 | 66.67% |
| Waiman Long | 7 | 8.64% | 1 | 33.33% |
| Total | 81 | 100.00% | 3 | 100.00% |
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));
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 38 | 100.00% | 2 | 100.00% |
| Total | 38 | 100.00% | 2 | 100.00% |
static struct cftype debug_legacy_files[] = {
{
.name = "taskcount",
.read_u64 = debug_taskcount_read,
},
{
.name = "current_css_set",
.seq_show = current_css_set_read,
.flags = CFTYPE_ONLY_ON_ROOT,
},
{
.name = "current_css_set_refcount",
.read_u64 = current_css_set_refcount_read,
.flags = CFTYPE_ONLY_ON_ROOT,
},
{
.name = "current_css_set_cg_links",
.seq_show = current_css_set_cg_links_read,
.flags = CFTYPE_ONLY_ON_ROOT,
},
{
.name = "cgroup_css_links",
.seq_show = cgroup_css_links_read,
},
{
.name = "cgroup_subsys_states",
.seq_show = cgroup_subsys_states_read,
},
{
.name = "cgroup_masks",
.seq_show = cgroup_masks_read,
},
{
.name = "releasable",
.read_u64 = releasable_read,
},
{ } /* terminate */
};
static struct cftype debug_files[] = {
{
.name = "taskcount",
.read_u64 = debug_taskcount_read,
},
{
.name = "current_css_set",
.seq_show = current_css_set_read,
.flags = CFTYPE_ONLY_ON_ROOT,
},
{
.name = "current_css_set_refcount",
.read_u64 = current_css_set_refcount_read,
.flags = CFTYPE_ONLY_ON_ROOT,
},
{
.name = "current_css_set_cg_links",
.seq_show = current_css_set_cg_links_read,
.flags = CFTYPE_ONLY_ON_ROOT,
},
{
.name = "css_links",
.seq_show = cgroup_css_links_read,
},
{
.name = "csses",
.seq_show = cgroup_subsys_states_read,
},
{
.name = "masks",
.seq_show = cgroup_masks_read,
},
{ } /* terminate */
};
struct cgroup_subsys debug_cgrp_subsys = {
.css_alloc = debug_css_alloc,
.css_free = debug_css_free,
.legacy_cftypes = debug_legacy_files,
};
/*
* On v2, debug is an implicit controller enabled by "cgroup_debug" boot
* parameter.
*/
static int __init enable_cgroup_debug(char *str)
{
debug_cgrp_subsys.dfl_cftypes = debug_files;
debug_cgrp_subsys.implicit_on_dfl = true;
debug_cgrp_subsys.threaded = true;
return 1;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Tejun Heo | 28 | 87.50% | 2 | 66.67% |
| Waiman Long | 4 | 12.50% | 1 | 33.33% |
| Total | 32 | 100.00% | 3 | 100.00% |
__setup("cgroup_debug", enable_cgroup_debug);
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Waiman Long | 1277 | 81.34% | 4 | 40.00% |
| Tejun Heo | 290 | 18.47% | 4 | 40.00% |
| Wang Long | 2 | 0.13% | 1 | 10.00% |
| Greg Kroah-Hartman | 1 | 0.06% | 1 | 10.00% |
| Total | 1570 | 100.00% | 10 | 100.00% |
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.