diff options
| -rw-r--r-- | fs/proc/base.c | 78 | ||||
| -rw-r--r-- | kernel/sched/auto_group.c | 68 | ||||
| -rw-r--r-- | kernel/sched/auto_group.h | 9 | ||||
| -rw-r--r-- | kernel/sysctl.c | 6 |
4 files changed, 147 insertions, 14 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index 587631e1cd0..9e28356a959 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1272,6 +1272,81 @@ static const struct file_operations proc_pid_sched_operations = { #endif +#ifdef CONFIG_SCHED_AUTOGROUP +/* + * Print out autogroup related information: + */ +static int sched_autogroup_show(struct seq_file *m, void *v) +{ + struct inode *inode = m->private; + struct task_struct *p; + + p = get_proc_task(inode); + if (!p) + return -ESRCH; + proc_sched_autogroup_show_task(p, m); + + put_task_struct(p); + + return 0; +} + +static ssize_t +sched_autogroup_write(struct file *file, const char __user *buf, + size_t count, loff_t *offset) +{ + struct inode *inode = file->f_path.dentry->d_inode; + struct task_struct *p; + char buffer[PROC_NUMBUF]; + int nice; + int err; + + memset(buffer, 0, sizeof(buffer)); + if (count > sizeof(buffer) - 1) + count = sizeof(buffer) - 1; + if (copy_from_user(buffer, buf, count)) + return -EFAULT; + + err = kstrtoint(strstrip(buffer), 0, &nice); + if (err < 0) + return err; + + p = get_proc_task(inode); + if (!p) + return -ESRCH; + + err = proc_sched_autogroup_set_nice(p, nice); + if (err) + count = err; + + put_task_struct(p); + + return count; +} + +static int sched_autogroup_open(struct inode *inode, struct file *filp) +{ + int ret; + + ret = single_open(filp, sched_autogroup_show, NULL); + if (!ret) { + struct seq_file *m = filp->private_data; + + m->private = inode; + } + return ret; +} + +static const struct file_operations proc_pid_sched_autogroup_operations = { + .open = sched_autogroup_open, + .read = seq_read, + .write = sched_autogroup_write, + .llseek = seq_lseek, + .release = single_release, +}; + +#endif /* CONFIG_SCHED_AUTOGROUP */ + static ssize_t comm_write(struct file *file, const char __user *buf, size_t count, loff_t *offset) { @@ -2583,6 +2658,9 @@ static const struct pid_entry tgid_base_stuff[] = { #ifdef CONFIG_SCHED_DEBUG REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), #endif +#ifdef CONFIG_SCHED_AUTOGROUP + REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations), +#endif REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations), #ifdef CONFIG_HAVE_ARCH_TRACEHOOK INF("syscall", S_IRUGO, proc_pid_syscall), diff --git a/kernel/sched/auto_group.c b/kernel/sched/auto_group.c index 0f1bacb005a..0984a21076a 100644 --- a/kernel/sched/auto_group.c +++ b/kernel/sched/auto_group.c @@ -110,9 +110,6 @@ out_fail: bool task_wants_autogroup(struct task_struct *p, struct task_group *tg) { - if (!sysctl_sched_autogroup_enabled) - return false; - if (tg != &root_task_group) return false; @@ -146,11 +143,15 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag) p->signal->autogroup = autogroup_kref_get(ag); + if (!ACCESS_ONCE(sysctl_sched_autogroup_enabled)) + goto out; + t = p; do { sched_move_task(t); } while_each_thread(p, t); +out: unlock_task_sighand(p, &flags); autogroup_kref_put(prev); } @@ -158,11 +159,8 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag) /* Allocates GFP_KERNEL, cannot be called under any spinlock */ void sched_autogroup_create_attach(struct task_struct *p) { - struct autogroup *ag; + struct autogroup *ag = autogroup_create(); - if (!sysctl_sched_autogroup_enabled) - return; - ag = autogroup_create(); autogroup_move_group(p, ag); /* drop extra reference added by autogroup_create() */ autogroup_kref_put(ag); @@ -178,15 +176,11 @@ EXPORT_SYMBOL(sched_autogroup_detach); void sched_autogroup_fork(struct signal_struct *sig) { - if (!sysctl_sched_autogroup_enabled) - return; sig->autogroup = autogroup_task_get(current); } void sched_autogroup_exit(struct signal_struct *sig) { - if (!sysctl_sched_autogroup_enabled) - return; autogroup_kref_put(sig->autogroup); } @@ -199,6 +193,58 @@ static int __init setup_autogroup(char *str) __setup("noautogroup", setup_autogroup); +#ifdef CONFIG_PROC_FS + +int proc_sched_autogroup_set_nice(struct task_struct *p, int nice) +{ + static unsigned long next = INITIAL_JIFFIES; + struct autogroup *ag; + int err; + + if (nice < -20 || nice > 19) + return -EINVAL; + + err = security_task_setnice(current, nice); + if (err) + return err; + + if (nice < 0 && !can_nice(current, nice)) + return -EPERM; + + /* this is a heavy operation taking global locks.. */ + if (!capable(CAP_SYS_ADMIN) && time_before(jiffies, next)) + return -EAGAIN; + + next = HZ / 10 + jiffies; + ag = autogroup_task_get(p); + + down_write(&ag->lock); + err = sched_group_set_shares(ag->tg, prio_to_weight[nice + 20]); + if (!err) + ag->nice = nice; + up_write(&ag->lock); + + autogroup_kref_put(ag); + + return err; +} + +void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m) +{ + struct autogroup *ag = autogroup_task_get(p); + + if (!task_group_is_autogroup(ag->tg)) + goto out; + + down_read(&ag->lock); + seq_printf(m, "/autogroup-%ld nice %d\n", ag->id, ag->nice); + up_read(&ag->lock); + +out: + autogroup_kref_put(ag); +} +#endif /* CONFIG_PROC_FS */ + #ifdef CONFIG_SCHED_DEBUG int autogroup_path(struct task_group *tg, char *buf, int buflen) { diff --git a/kernel/sched/auto_group.h b/kernel/sched/auto_group.h index 4552c6bf79d..8bd04714281 100644 --- a/kernel/sched/auto_group.h +++ b/kernel/sched/auto_group.h @@ -4,6 +4,11 @@ #include <linux/rwsem.h> struct autogroup { + /* + * reference doesn't mean how many thread attach to this + * autogroup now. It just stands for the number of task + * could use this autogroup. + */ struct kref kref; struct task_group *tg; struct rw_semaphore lock; @@ -24,7 +29,9 @@ extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg); static inline struct task_group * autogroup_task_group(struct task_struct *p, struct task_group *tg) { - if (task_wants_autogroup(p, tg)) + int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled); + + if (enabled && task_wants_autogroup(p, tg)) return p->signal->autogroup->tg; return tg; diff --git a/kernel/sysctl.c b/kernel/sysctl.c index b0fa5ad0987..26f65eaa01f 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -367,8 +367,10 @@ static struct ctl_table kern_table[] = { .procname = "sched_autogroup_enabled", .data = &sysctl_sched_autogroup_enabled, .maxlen = sizeof(unsigned int), - .mode = 0444, - .proc_handler = proc_dointvec, + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, #endif #ifdef CONFIG_CFS_BANDWIDTH |