diff options
Diffstat (limited to 'kernel/cpuset.c')
| -rw-r--r-- | kernel/cpuset.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 39c1a4c1c5a9..345ace5117de 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -240,6 +240,17 @@ static struct cpuset top_cpuset = { static DEFINE_MUTEX(callback_mutex); /* + * cpuset_buffer_lock protects both the cpuset_name and cpuset_nodelist + * buffers. They are statically allocated to prevent using excess stack + * when calling cpuset_print_task_mems_allowed(). + */ +#define CPUSET_NAME_LEN (128) +#define CPUSET_NODELIST_LEN (256) +static char cpuset_name[CPUSET_NAME_LEN]; +static char cpuset_nodelist[CPUSET_NODELIST_LEN]; +static DEFINE_SPINLOCK(cpuset_buffer_lock); + +/* * This is ugly, but preserves the userspace API for existing cpuset * users. If someone tries to mount the "cpuset" filesystem, we * silently switch it to mount "cgroup" instead @@ -2356,6 +2367,29 @@ int cpuset_mems_allowed_intersects(const struct task_struct *tsk1, return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed); } +/** + * cpuset_print_task_mems_allowed - prints task's cpuset and mems_allowed + * @task: pointer to task_struct of some task. + * + * Description: Prints @task's name, cpuset name, and cached copy of its + * mems_allowed to the kernel log. Must hold task_lock(task) to allow + * dereferencing task_cs(task). + */ +void cpuset_print_task_mems_allowed(struct task_struct *tsk) +{ + struct dentry *dentry; + + dentry = task_cs(tsk)->css.cgroup->dentry; + spin_lock(&cpuset_buffer_lock); + snprintf(cpuset_name, CPUSET_NAME_LEN, + dentry ? (const char *)dentry->d_name.name : "/"); + nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN, + tsk->mems_allowed); + printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n", + tsk->comm, cpuset_name, cpuset_nodelist); + spin_unlock(&cpuset_buffer_lock); +} + /* * Collection of memory_pressure is suppressed unless * this flag is enabled by writing "1" to the special |