Merge branch 'sched/urgent' into sched/core

Merge in fixes before we queue up dependent bits, to avoid conflicts.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 144a96732dd7d602df0d5f8a504e435cfdb07229..5c1ad58c802827a90fbf8f98c36e596de5e6bda8 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1165,81 +1165,6 @@ 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)
 {
@@ -2549,9 +2474,6 @@ static const struct pid_entry tgid_base_stuff[] = {
        INF("limits",     S_IRUGO, proc_pid_limits),
 #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

diff --git a/kernel/sched/auto_group.c b/kernel/sched/auto_group.c
index 0984a21076a3ed8a37e56d5381bff6320d8fa5f2..0f1bacb005a4f5f2761b032dfec8a32e913fab54 100644 (file)
--- a/kernel/sched/auto_group.c
+++ b/kernel/sched/auto_group.c
@@ -110,6 +110,9 @@ 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;
 
@@ -143,15 +146,11 @@ 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);
 }
@@ -159,8 +158,11 @@ out:
 /* Allocates GFP_KERNEL, cannot be called under any spinlock */
 void sched_autogroup_create_attach(struct task_struct *p)
 {
-       struct autogroup *ag = autogroup_create();
+       struct autogroup *ag;
 
+       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);
@@ -176,11 +178,15 @@ 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);
 }
 
@@ -193,58 +199,6 @@ 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 8bd047142816dea81894bb27ccc3c78a38ac3d61..4552c6bf79d2e1720054d2f5abe417ea22a9f49a 100644 (file)
--- a/kernel/sched/auto_group.h
+++ b/kernel/sched/auto_group.h
@@ -4,11 +4,6 @@
 #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;
@@ -29,9 +24,7 @@ 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)
 {
-       int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled);
-
-       if (enabled && task_wants_autogroup(p, tg))
+       if (task_wants_autogroup(p, tg))
                return p->signal->autogroup->tg;
 
        return tg;

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index a319d56c760507ec8477c3e7662d11a16fec12b1..59e072b2db970b80eb2eac7b435d297305640e2a 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3330,7 +3330,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
         * Batch and idle tasks do not preempt non-idle tasks (their preemption
         * is driven by the tick):
         */
-       if (unlikely(p->policy != SCHED_NORMAL))
+       if (unlikely(p->policy != SCHED_NORMAL) || !sched_feat(WAKEUP_PREEMPTION))
                return;
 
        find_matching_se(&se, &pse);

diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index eebefcad7027a0587977fb1cecaeb0d13cac79a0..e68e69ab917dcc244577504027e1b357230c55fe 100644 (file)
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -31,6 +31,11 @@ SCHED_FEAT(LAST_BUDDY, true)
  */
 SCHED_FEAT(CACHE_HOT_BUDDY, true)
 
+/*
+ * Allow wakeup-time preemption of the current task:
+ */
+SCHED_FEAT(WAKEUP_PREEMPTION, true)
+
 /*
  * Use arch dependent cpu power functions
  */

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 26f65eaa01f9c94366aa5156f9c304bbc589808f..b0fa5ad09873f874775cc72ffd534bfec825f639 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -367,10 +367,8 @@ static struct ctl_table kern_table[] = {
                .procname       = "sched_autogroup_enabled",
                .data           = &sysctl_sched_autogroup_enabled,
                .maxlen         = sizeof(unsigned int),
-               .mode           = 0644,
-               .proc_handler   = proc_dointvec_minmax,
-               .extra1         = &zero,
-               .extra2         = &one,
+               .mode           = 0444,
+               .proc_handler   = proc_dointvec,
        },
 #endif
 #ifdef CONFIG_CFS_BANDWIDTH