diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 2 | ||||
| -rw-r--r-- | fs/proc/base.c | 79 | ||||
| -rw-r--r-- | include/linux/sched.h | 23 | ||||
| -rw-r--r-- | init/Kconfig | 13 | ||||
| -rw-r--r-- | kernel/fork.c | 5 | ||||
| -rw-r--r-- | kernel/sched.c | 13 | ||||
| -rw-r--r-- | kernel/sched_autogroup.c | 229 | ||||
| -rw-r--r-- | kernel/sched_autogroup.h | 32 | ||||
| -rw-r--r-- | kernel/sched_debug.c | 47 | ||||
| -rw-r--r-- | kernel/sys.c | 4 | ||||
| -rw-r--r-- | kernel/sysctl.c | 11 |
11 files changed, 409 insertions, 49 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 92e83e5..86820a72 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1622,6 +1622,8 @@ and is between 256 and 4096 characters. It is defined in the file noapic [SMP,APIC] Tells the kernel to not make use of any IOAPICs that may be present in the system. + noautogroup Disable scheduler automatic task group creation. + nobats [PPC] Do not use BATs for mapping kernel lowmem on "Classic" PPC cores. diff --git a/fs/proc/base.c b/fs/proc/base.c index f3d02ca..2fa0ce2 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1407,6 +1407,82 @@ 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]; + long 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 = strict_strtol(strstrip(buffer), 0, &nice); + if (err) + return -EINVAL; + + p = get_proc_task(inode); + if (!p) + return -ESRCH; + + err = nice; + err = proc_sched_autogroup_set_nice(p, &err); + 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) { @@ -2733,6 +2809,9 @@ 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_IRUSR, proc_pid_syscall), diff --git a/include/linux/sched.h b/include/linux/sched.h index a5b92c7..9c2d46d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -509,6 +509,8 @@ struct thread_group_cputimer { spinlock_t lock; }; +struct autogroup; + /* * NOTE! "signal_struct" does not have it's own * locking, because a shared signal_struct always @@ -576,6 +578,9 @@ struct signal_struct { struct tty_struct *tty; /* NULL if no tty */ +#ifdef CONFIG_SCHED_AUTOGROUP + struct autogroup *autogroup; +#endif /* * Cumulative resource counters for dead threads in the group, * and for reaped dead child processes forked by this group. @@ -1927,6 +1932,24 @@ int sched_rt_handler(struct ctl_table *table, int write, extern unsigned int sysctl_sched_compat_yield; +#ifdef CONFIG_SCHED_AUTOGROUP +extern unsigned int sysctl_sched_autogroup_enabled; + +extern void sched_autogroup_create_attach(struct task_struct *p); +extern void sched_autogroup_detach(struct task_struct *p); +extern void sched_autogroup_fork(struct signal_struct *sig); +extern void sched_autogroup_exit(struct signal_struct *sig); +#ifdef CONFIG_PROC_FS +extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m); +extern int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice); +#endif +#else +static inline void sched_autogroup_create_attach(struct task_struct *p) { } +static inline void sched_autogroup_detach(struct task_struct *p) { } +static inline void sched_autogroup_fork(struct signal_struct *sig) { } +static inline void sched_autogroup_exit(struct signal_struct *sig) { } +#endif + #ifdef CONFIG_RT_MUTEXES extern int rt_mutex_getprio(struct task_struct *p); extern void rt_mutex_setprio(struct task_struct *p, int prio); diff --git a/init/Kconfig b/init/Kconfig index 88c1046..f1bba0a 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -728,6 +728,19 @@ config NET_NS endif # NAMESPACES +config SCHED_AUTOGROUP + bool "Automatic process group scheduling" + select EVENTFD + select CGROUPS + select CGROUP_SCHED + select FAIR_GROUP_SCHED + help + This option optimizes the scheduler for common desktop workloads by + automatically creating and populating task groups. This separation + of workloads isolates aggressive CPU burners (like build jobs) from + desktop applications. Task group autogeneration is currently based + upon task session. + config MM_OWNER bool diff --git a/kernel/fork.c b/kernel/fork.c index 3b159c5..b6f2475 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -174,8 +174,10 @@ static inline void free_signal_struct(struct signal_struct *sig) static inline void put_signal_struct(struct signal_struct *sig) { - if (atomic_dec_and_test(&sig->sigcnt)) + if (atomic_dec_and_test(&sig->sigcnt)) { + sched_autogroup_exit(sig); free_signal_struct(sig); + } } void __put_task_struct(struct task_struct *tsk) @@ -904,6 +906,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) posix_cpu_timers_init_group(sig); tty_audit_fork(sig); + sched_autogroup_fork(sig); sig->oom_adj = current->signal->oom_adj; sig->oom_score_adj = current->signal->oom_score_adj; diff --git a/kernel/sched.c b/kernel/sched.c index 66ef579..b646dad 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -79,6 +79,7 @@ #include "sched_cpupri.h" #include "workqueue_sched.h" +#include "sched_autogroup.h" #define CREATE_TRACE_POINTS #include <trace/events/sched.h> @@ -271,6 +272,10 @@ struct task_group { struct task_group *parent; struct list_head siblings; struct list_head children; + +#ifdef CONFIG_SCHED_AUTOGROUP + struct autogroup *autogroup; +#endif }; #define root_task_group init_task_group @@ -603,11 +608,14 @@ static inline int cpu_of(struct rq *rq) */ static inline struct task_group *task_group(struct task_struct *p) { + struct task_group *tg; struct cgroup_subsys_state *css; css = task_subsys_state_check(p, cpu_cgroup_subsys_id, lockdep_is_held(&task_rq(p)->lock)); - return container_of(css, struct task_group, css); + tg = container_of(css, struct task_group, css); + + return autogroup_task_group(p, tg); } /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ @@ -1869,6 +1877,7 @@ static void sched_irq_time_avg_update(struct rq *rq, u64 curr_irq_time) { } #include "sched_idletask.c" #include "sched_fair.c" #include "sched_rt.c" +#include "sched_autogroup.c" #include "sched_stoptask.c" #ifdef CONFIG_SCHED_DEBUG # include "sched_debug.c" @@ -7750,7 +7759,7 @@ void __init sched_init(void) #ifdef CONFIG_CGROUP_SCHED list_add(&init_task_group.list, &task_groups); INIT_LIST_HEAD(&init_task_group.children); - + autogroup_init(&init_task); #endif /* CONFIG_CGROUP_SCHED */ for_each_possible_cpu(i) { diff --git a/kernel/sched_autogroup.c b/kernel/sched_autogroup.c new file mode 100644 index 0000000..57a7ac28 --- /dev/null +++ b/kernel/sched_autogroup.c @@ -0,0 +1,229 @@ +#ifdef CONFIG_SCHED_AUTOGROUP + +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/kallsyms.h> +#include <linux/utsname.h> + +unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1; +static struct autogroup autogroup_default; +static atomic_t autogroup_seq_nr; + +static void autogroup_init(struct task_struct *init_task) +{ + autogroup_default.tg = &init_task_group; + init_task_group.autogroup = &autogroup_default; + kref_init(&autogroup_default.kref); + init_rwsem(&autogroup_default.lock); + init_task->signal->autogroup = &autogroup_default; +} + +static inline void autogroup_free(struct task_group *tg) +{ + kfree(tg->autogroup); +} + +static inline void autogroup_destroy(struct kref *kref) +{ + struct autogroup *ag = container_of(kref, struct autogroup, kref); + + sched_destroy_group(ag->tg); +} + +static inline void autogroup_kref_put(struct autogroup *ag) +{ + kref_put(&ag->kref, autogroup_destroy); +} + +static inline struct autogroup *autogroup_kref_get(struct autogroup *ag) +{ + kref_get(&ag->kref); + return ag; +} + +static inline struct autogroup *autogroup_create(void) +{ + struct autogroup *ag = kzalloc(sizeof(*ag), GFP_KERNEL); + struct task_group *tg; + + if (!ag) + goto out_fail; + + tg = sched_create_group(&init_task_group); + + if (IS_ERR(tg)) + goto out_free; + + kref_init(&ag->kref); + init_rwsem(&ag->lock); + ag->id = atomic_inc_return(&autogroup_seq_nr); + ag->tg = tg; + tg->autogroup = ag; + + return ag; + +out_free: + kfree(ag); +out_fail: + if (printk_ratelimit()) { + printk(KERN_WARNING "autogroup_create: %s failure.\n", + ag ? "sched_create_group()" : "kmalloc()"); + } + + return autogroup_kref_get(&autogroup_default); +} + +static inline bool +task_wants_autogroup(struct task_struct *p, struct task_group *tg) +{ + if (tg != &root_task_group) + return false; + + if (p->sched_class != &fair_sched_class) + return false; + + /* + * We can only assume the task group can't go away on us if + * autogroup_move_group() can see us on ->thread_group list. + */ + if (p->flags & PF_EXITING) + return false; + + return true; +} + +static inline struct task_group * +autogroup_task_group(struct task_struct *p, struct task_group *tg) +{ + int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled); + + if (enabled && task_wants_autogroup(p, tg)) + return p->signal->autogroup->tg; + + return tg; +} + +static void +autogroup_move_group(struct task_struct *p, struct autogroup *ag) +{ + struct autogroup *prev; + struct task_struct *t; + unsigned long flags; + + BUG_ON(!lock_task_sighand(p, &flags)); + + prev = p->signal->autogroup; + if (prev == ag) { + unlock_task_sighand(p, &flags); + return; + } + + p->signal->autogroup = autogroup_kref_get(ag); + + t = p; + do { + sched_move_task(t); + } while_each_thread(p, t); + + unlock_task_sighand(p, &flags); + autogroup_kref_put(prev); +} + +/* Allocates GFP_KERNEL, cannot be called under any spinlock */ +void sched_autogroup_create_attach(struct task_struct *p) +{ + struct autogroup *ag = autogroup_create(); + + autogroup_move_group(p, ag); + /* drop extra refrence added by autogroup_create() */ + autogroup_kref_put(ag); +} +EXPORT_SYMBOL(sched_autogroup_create_attach); + +/* Cannot be called under siglock. Currently has no users */ +void sched_autogroup_detach(struct task_struct *p) +{ + autogroup_move_group(p, &autogroup_default); +} +EXPORT_SYMBOL(sched_autogroup_detach); + +void sched_autogroup_fork(struct signal_struct *sig) +{ + struct task_struct *p = current; + + spin_lock_irq(&p->sighand->siglock); + sig->autogroup = autogroup_kref_get(p->signal->autogroup); + spin_unlock_irq(&p->sighand->siglock); +} + +void sched_autogroup_exit(struct signal_struct *sig) +{ + autogroup_kref_put(sig->autogroup); +} + +static int __init setup_autogroup(char *str) +{ + sysctl_sched_autogroup_enabled = 0; + + return 1; +} + +__setup("noautogroup", setup_autogroup); + +#ifdef CONFIG_PROC_FS + +/* Called with siglock held. */ +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_kref_get(p->signal->autogroup); + + 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_kref_get(p->signal->autogroup); + + down_read(&ag->lock); + seq_printf(m, "/autogroup-%ld nice %d\n", ag->id, ag->nice); + up_read(&ag->lock); + + autogroup_kref_put(ag); +} +#endif /* CONFIG_PROC_FS */ + +#ifdef CONFIG_SCHED_DEBUG +static inline int autogroup_path(struct task_group *tg, char *buf, int buflen) +{ + return snprintf(buf, buflen, "%s-%ld", "/autogroup", tg->autogroup->id); +} +#endif /* CONFIG_SCHED_DEBUG */ + +#endif /* CONFIG_SCHED_AUTOGROUP */ diff --git a/kernel/sched_autogroup.h b/kernel/sched_autogroup.h new file mode 100644 index 0000000..5358e24 --- /dev/null +++ b/kernel/sched_autogroup.h @@ -0,0 +1,32 @@ +#ifdef CONFIG_SCHED_AUTOGROUP + +struct autogroup { + struct kref kref; + struct task_group *tg; + struct rw_semaphore lock; + unsigned long id; + int nice; +}; + +static inline struct task_group * +autogroup_task_group(struct task_struct *p, struct task_group *tg); + +#else /* !CONFIG_SCHED_AUTOGROUP */ + +static inline void autogroup_init(struct task_struct *init_task) { } +static inline void autogroup_free(struct task_group *tg) { } + +static inline struct task_group * +autogroup_task_group(struct task_struct *p, struct task_group *tg) +{ + return tg; +} + +#ifdef CONFIG_SCHED_DEBUG +static inline int autogroup_path(struct task_group *tg, char *buf, int buflen) +{ + return 0; +} +#endif + +#endif /* CONFIG_SCHED_AUTOGROUP */ diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c index e95b774..1dfae3d 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched_debug.c @@ -54,8 +54,7 @@ static unsigned long nsec_low(unsigned long long nsec) #define SPLIT_NS(x) nsec_high(x), nsec_low(x) #ifdef CONFIG_FAIR_GROUP_SCHED -static void print_cfs_group_stats(struct seq_file *m, int cpu, - struct task_group *tg) +static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg) { struct sched_entity *se = tg->se[cpu]; if (!se) @@ -110,16 +109,6 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p) 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L); #endif -#ifdef CONFIG_CGROUP_SCHED - { - char path[64]; - - rcu_read_lock(); - cgroup_path(task_group(p)->css.cgroup, path, sizeof(path)); - rcu_read_unlock(); - SEQ_printf(m, " %s", path); - } -#endif SEQ_printf(m, "\n"); } @@ -147,19 +136,6 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu) read_unlock_irqrestore(&tasklist_lock, flags); } -#if defined(CONFIG_CGROUP_SCHED) && \ - (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)) -static void task_group_path(struct task_group *tg, char *buf, int buflen) -{ - /* may be NULL if the underlying cgroup isn't fully-created yet */ - if (!tg->css.cgroup) { - buf[0] = '\0'; - return; - } - cgroup_path(tg->css.cgroup, buf, buflen); -} -#endif - void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) { s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1, @@ -168,16 +144,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) struct sched_entity *last; unsigned long flags; -#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED) - char path[128]; - struct task_group *tg = cfs_rq->tg; - - task_group_path(tg, path, sizeof(path)); - - SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path); -#else SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu); -#endif SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock", SPLIT_NS(cfs_rq->exec_clock)); @@ -215,7 +182,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) SEQ_printf(m, " .%-30s: %ld\n", "load_contrib", cfs_rq->load_contribution); SEQ_printf(m, " .%-30s: %d\n", "load_tg", - atomic_read(&tg->load_weight)); + atomic_read(&cfs_rq->tg->load_weight)); #endif print_cfs_group_stats(m, cpu, cfs_rq->tg); @@ -224,17 +191,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq) { -#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED) - char path[128]; - struct task_group *tg = rt_rq->tg; - - task_group_path(tg, path, sizeof(path)); - - SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path); -#else SEQ_printf(m, "\nrt_rq[%d]:\n", cpu); -#endif - #define P(x) \ SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x)) diff --git a/kernel/sys.c b/kernel/sys.c index 7f5a0cd..2745dcd 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1080,8 +1080,10 @@ SYSCALL_DEFINE0(setsid) err = session; out: write_unlock_irq(&tasklist_lock); - if (err > 0) + if (err > 0) { proc_sid_connector(group_leader); + sched_autogroup_create_attach(group_leader); + } return err; } diff --git a/kernel/sysctl.c b/kernel/sysctl.c index a00fdef..121e4ff 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -370,6 +370,17 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, +#ifdef CONFIG_SCHED_AUTOGROUP + { + .procname = "sched_autogroup_enabled", + .data = &sysctl_sched_autogroup_enabled, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_dointvec, + .extra1 = &zero, + .extra2 = &one, + }, +#endif #ifdef CONFIG_PROVE_LOCKING { .procname = "prove_locking", |
