summaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Kconfig.preempt15
-rw-r--r--kernel/audit.c19
-rw-r--r--kernel/auditsc.c2
-rw-r--r--kernel/cgroup.c4
-rw-r--r--kernel/cpuset.c4
-rw-r--r--kernel/exit.c98
-rw-r--r--kernel/kprobes.c52
-rw-r--r--kernel/lockdep.c8
-rw-r--r--kernel/marker.c9
-rw-r--r--kernel/module.c24
-rw-r--r--kernel/power/process.c29
-rw-r--r--kernel/printk.c2
-rw-r--r--kernel/rcupreempt.c233
-rw-r--r--kernel/res_counter.c1
-rw-r--r--kernel/sched.c338
-rw-r--r--kernel/sched_fair.c142
-rw-r--r--kernel/sched_rt.c10
-rw-r--r--kernel/signal.c16
-rw-r--r--kernel/softirq.c1
-rw-r--r--kernel/softlockup.c13
-rw-r--r--kernel/sysctl.c18
-rw-r--r--kernel/time/ntp.c23
-rw-r--r--kernel/time/tick-sched.c5
-rw-r--r--kernel/time/timekeeping.c6
24 files changed, 555 insertions, 517 deletions
diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index 0669b70fa6a3..9fdba03dc1fc 100644
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -52,8 +52,23 @@ config PREEMPT
endchoice
+config PREEMPT_RCU
+ bool "Preemptible RCU"
+ depends on PREEMPT
+ default n
+ help
+ This option reduces the latency of the kernel by making certain
+ RCU sections preemptible. Normally RCU code is non-preemptible, if
+ this option is selected then read-only RCU sections become
+ preemptible. This helps latency, but may expose bugs due to
+ now-naive assumptions about each RCU read-side critical section
+ remaining on a given CPU through its execution.
+
+ Say N if you are unsure.
+
config RCU_TRACE
bool "Enable tracing for RCU - currently stats in debugfs"
+ depends on PREEMPT_RCU
select DEBUG_FS
default y
help
diff --git a/kernel/audit.c b/kernel/audit.c
index 2eeea9a14240..10c4930c2bbf 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -170,7 +170,9 @@ void audit_panic(const char *message)
printk(KERN_ERR "audit: %s\n", message);
break;
case AUDIT_FAIL_PANIC:
- panic("audit: %s\n", message);
+ /* test audit_pid since printk is always losey, why bother? */
+ if (audit_pid)
+ panic("audit: %s\n", message);
break;
}
}
@@ -352,6 +354,7 @@ static int kauditd_thread(void *dummy)
if (err < 0) {
BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */
printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
+ audit_log_lost("auditd dissapeared\n");
audit_pid = 0;
}
} else {
@@ -1350,17 +1353,19 @@ void audit_log_end(struct audit_buffer *ab)
if (!audit_rate_check()) {
audit_log_lost("rate limit exceeded");
} else {
+ struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
if (audit_pid) {
- struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
skb_queue_tail(&audit_skb_queue, ab->skb);
ab->skb = NULL;
wake_up_interruptible(&kauditd_wait);
- } else if (printk_ratelimit()) {
- struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
- printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, ab->skb->data + NLMSG_SPACE(0));
- } else {
- audit_log_lost("printk limit exceeded\n");
+ } else if (nlh->nlmsg_type != AUDIT_EOE) {
+ if (printk_ratelimit()) {
+ printk(KERN_NOTICE "type=%d %s\n",
+ nlh->nlmsg_type,
+ ab->skb->data + NLMSG_SPACE(0));
+ } else
+ audit_log_lost("printk limit exceeded\n");
}
}
audit_buffer_free(ab);
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 2087d6de67ea..782262e4107d 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1070,7 +1070,7 @@ static int audit_log_single_execve_arg(struct audit_context *context,
* so we can be sure nothing was lost.
*/
if ((i == 0) && (too_long))
- audit_log_format(*ab, "a%d_len=%ld ", arg_num,
+ audit_log_format(*ab, "a%d_len=%zu ", arg_num,
has_cntl ? 2*len : len);
/*
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index d8abe996e009..e9c2fb01e89b 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2232,7 +2232,6 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
mutex_lock(&cgroup_mutex);
- cgrp->flags = 0;
INIT_LIST_HEAD(&cgrp->sibling);
INIT_LIST_HEAD(&cgrp->children);
INIT_LIST_HEAD(&cgrp->css_sets);
@@ -2242,6 +2241,9 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
cgrp->root = parent->root;
cgrp->top_cgroup = parent->top_cgroup;
+ if (notify_on_release(parent))
+ set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
+
for_each_subsys(root, ss) {
struct cgroup_subsys_state *css = ss->create(ss, cgrp);
if (IS_ERR(css)) {
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3e296ed81d4d..a1b61f414228 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -322,8 +322,8 @@ static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask)
* Call without callback_mutex or task_lock() held. May be
* called with or without cgroup_mutex held. Thanks in part to
* 'the_top_cpuset_hack', the task's cpuset pointer will never
- * be NULL. This routine also might acquire callback_mutex and
- * current->mm->mmap_sem during call.
+ * be NULL. This routine also might acquire callback_mutex during
+ * call.
*
* Reading current->cpuset->mems_generation doesn't need task_lock
* to guard the current->cpuset derefence, because it is guarded
diff --git a/kernel/exit.c b/kernel/exit.c
index 506a957b665a..53872bf993fa 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -214,20 +214,19 @@ struct pid *session_of_pgrp(struct pid *pgrp)
static int will_become_orphaned_pgrp(struct pid *pgrp, struct task_struct *ignored_task)
{
struct task_struct *p;
- int ret = 1;
do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
- if (p == ignored_task
- || p->exit_state
- || is_global_init(p->real_parent))
+ if ((p == ignored_task) ||
+ (p->exit_state && thread_group_empty(p)) ||
+ is_global_init(p->real_parent))
continue;
+
if (task_pgrp(p->real_parent) != pgrp &&
- task_session(p->real_parent) == task_session(p)) {
- ret = 0;
- break;
- }
+ task_session(p->real_parent) == task_session(p))
+ return 0;
} while_each_pid_task(pgrp, PIDTYPE_PGID, p);
- return ret; /* (sighing) "Often!" */
+
+ return 1;
}
int is_current_pgrp_orphaned(void)
@@ -255,6 +254,37 @@ static int has_stopped_jobs(struct pid *pgrp)
return retval;
}
+/*
+ * Check to see if any process groups have become orphaned as
+ * a result of our exiting, and if they have any stopped jobs,
+ * send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
+ */
+static void
+kill_orphaned_pgrp(struct task_struct *tsk, struct task_struct *parent)
+{
+ struct pid *pgrp = task_pgrp(tsk);
+ struct task_struct *ignored_task = tsk;
+
+ if (!parent)
+ /* exit: our father is in a different pgrp than
+ * we are and we were the only connection outside.
+ */
+ parent = tsk->real_parent;
+ else
+ /* reparent: our child is in a different pgrp than
+ * we are, and it was the only connection outside.
+ */
+ ignored_task = NULL;
+
+ if (task_pgrp(parent) != pgrp &&
+ task_session(parent) == task_session(tsk) &&
+ will_become_orphaned_pgrp(pgrp, ignored_task) &&
+ has_stopped_jobs(pgrp)) {
+ __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp);
+ __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp);
+ }
+}
+
/**
* reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd
*
@@ -635,22 +665,7 @@ reparent_thread(struct task_struct *p, struct task_struct *father, int traced)
p->exit_signal != -1 && thread_group_empty(p))
do_notify_parent(p, p->exit_signal);
- /*
- * process group orphan check
- * Case ii: Our child is in a different pgrp
- * than we are, and it was the only connection
- * outside, so the child pgrp is now orphaned.
- */
- if ((task_pgrp(p) != task_pgrp(father)) &&
- (task_session(p) == task_session(father))) {
- struct pid *pgrp = task_pgrp(p);
-
- if (will_become_orphaned_pgrp(pgrp, NULL) &&
- has_stopped_jobs(pgrp)) {
- __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp);
- __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp);
- }
- }
+ kill_orphaned_pgrp(p, father);
}
/*
@@ -735,11 +750,9 @@ static void forget_original_parent(struct task_struct *father)
* Send signals to all our closest relatives so that they know
* to properly mourn us..
*/
-static void exit_notify(struct task_struct *tsk)
+static void exit_notify(struct task_struct *tsk, int group_dead)
{
int state;
- struct task_struct *t;
- struct pid *pgrp;
/*
* This does two things:
@@ -753,25 +766,8 @@ static void exit_notify(struct task_struct *tsk)
exit_task_namespaces(tsk);
write_lock_irq(&tasklist_lock);
- /*
- * Check to see if any process groups have become orphaned
- * as a result of our exiting, and if they have any stopped
- * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
- *
- * Case i: Our father is in a different pgrp than we are
- * and we were the only connection outside, so our pgrp
- * is about to become orphaned.
- */
- t = tsk->real_parent;
-
- pgrp = task_pgrp(tsk);
- if ((task_pgrp(t) != pgrp) &&
- (task_session(t) == task_session(tsk)) &&
- will_become_orphaned_pgrp(pgrp, tsk) &&
- has_stopped_jobs(pgrp)) {
- __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp);
- __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp);
- }
+ if (group_dead)
+ kill_orphaned_pgrp(tsk->group_leader, NULL);
/* Let father know we died
*
@@ -788,8 +784,8 @@ static void exit_notify(struct task_struct *tsk)
* the same after a fork.
*/
if (tsk->exit_signal != SIGCHLD && tsk->exit_signal != -1 &&
- ( tsk->parent_exec_id != t->self_exec_id ||
- tsk->self_exec_id != tsk->parent_exec_id)
+ (tsk->parent_exec_id != tsk->real_parent->self_exec_id ||
+ tsk->self_exec_id != tsk->parent_exec_id)
&& !capable(CAP_KILL))
tsk->exit_signal = SIGCHLD;
@@ -986,7 +982,7 @@ NORET_TYPE void do_exit(long code)
module_put(tsk->binfmt->module);
proc_exit_connector(tsk);
- exit_notify(tsk);
+ exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA
mpol_free(tsk->mempolicy);
tsk->mempolicy = NULL;
@@ -1382,7 +1378,7 @@ unlock_sig:
if (!retval && infop)
retval = put_user(0, &infop->si_errno);
if (!retval && infop)
- retval = put_user(why, &infop->si_code);
+ retval = put_user((short)why, &infop->si_code);
if (!retval && infop)
retval = put_user(exit_code, &infop->si_status);
if (!retval && infop)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 7a86e6432338..fcfb580c3afc 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -498,27 +498,36 @@ static int __kprobes in_kprobes_functions(unsigned long addr)
return 0;
}
+/*
+ * If we have a symbol_name argument, look it up and add the offset field
+ * to it. This way, we can specify a relative address to a symbol.
+ */
+static kprobe_opcode_t __kprobes *kprobe_addr(struct kprobe *p)
+{
+ kprobe_opcode_t *addr = p->addr;
+ if (p->symbol_name) {
+ if (addr)
+ return NULL;
+ kprobe_lookup_name(p->symbol_name, addr);
+ }
+
+ if (!addr)
+ return NULL;
+ return (kprobe_opcode_t *)(((char *)addr) + p->offset);
+}
+
static int __kprobes __register_kprobe(struct kprobe *p,
unsigned long called_from)
{
int ret = 0;
struct kprobe *old_p;
struct module *probed_mod;
+ kprobe_opcode_t *addr;
- /*
- * If we have a symbol_name argument look it up,
- * and add it to the address. That way the addr
- * field can either be global or relative to a symbol.
- */
- if (p->symbol_name) {
- if (p->addr)
- return -EINVAL;
- kprobe_lookup_name(p->symbol_name, p->addr);
- }
-
- if (!p->addr)
+ addr = kprobe_addr(p);
+ if (!addr)
return -EINVAL;
- p->addr = (kprobe_opcode_t *)(((char *)p->addr)+ p->offset);
+ p->addr = addr;
if (!kernel_text_address((unsigned long) p->addr) ||
in_kprobes_functions((unsigned long) p->addr))
@@ -678,8 +687,7 @@ void __kprobes unregister_jprobe(struct jprobe *jp)
unregister_kprobe(&jp->kp);
}
-#ifdef ARCH_SUPPORTS_KRETPROBES
-
+#ifdef CONFIG_KRETPROBES
/*
* This kprobe pre_handler is registered with every kretprobe. When probe
* hits it will set up the return probe.
@@ -722,12 +730,12 @@ int __kprobes register_kretprobe(struct kretprobe *rp)
int ret = 0;
struct kretprobe_instance *inst;
int i;
- void *addr = rp->kp.addr;
+ void *addr;
if (kretprobe_blacklist_size) {
- if (addr == NULL)
- kprobe_lookup_name(rp->kp.symbol_name, addr);
- addr += rp->kp.offset;
+ addr = kprobe_addr(&rp->kp);
+ if (!addr)
+ return -EINVAL;
for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
if (kretprobe_blacklist[i].addr == addr)
@@ -769,8 +777,7 @@ int __kprobes register_kretprobe(struct kretprobe *rp)
return ret;
}
-#else /* ARCH_SUPPORTS_KRETPROBES */
-
+#else /* CONFIG_KRETPROBES */
int __kprobes register_kretprobe(struct kretprobe *rp)
{
return -ENOSYS;
@@ -781,8 +788,7 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p,
{
return 0;
}
-
-#endif /* ARCH_SUPPORTS_KRETPROBES */
+#endif /* CONFIG_KRETPROBES */
void __kprobes unregister_kretprobe(struct kretprobe *rp)
{
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 3574379f4d62..81a4e4a3f087 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -779,6 +779,10 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
* parallel walking of the hash-list safe:
*/
list_add_tail_rcu(&class->hash_entry, hash_head);
+ /*
+ * Add it to the global list of classes:
+ */
+ list_add_tail_rcu(&class->lock_entry, &all_lock_classes);
if (verbose(class)) {
graph_unlock();
@@ -2282,10 +2286,6 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this,
return 0;
break;
case LOCK_USED:
- /*
- * Add it to the global list of classes:
- */
- list_add_tail_rcu(&this->class->lock_entry, &all_lock_classes);
debug_atomic_dec(&nr_unused_locks);
break;
default:
diff --git a/kernel/marker.c b/kernel/marker.c
index 50effc01d9a2..48a4ea5afffd 100644
--- a/kernel/marker.c
+++ b/kernel/marker.c
@@ -698,14 +698,12 @@ int marker_probe_unregister(const char *name,
{
struct marker_entry *entry;
struct marker_probe_closure *old;
- int ret = 0;
+ int ret = -ENOENT;
mutex_lock(&markers_mutex);
entry = get_marker(name);
- if (!entry) {
- ret = -ENOENT;
+ if (!entry)
goto end;
- }
if (entry->rcu_pending)
rcu_barrier();
old = marker_entry_remove_probe(entry, probe, probe_private);
@@ -713,12 +711,15 @@ int marker_probe_unregister(const char *name,
marker_update_probes(); /* may update entry */
mutex_lock(&markers_mutex);
entry = get_marker(name);
+ if (!entry)
+ goto end;
entry->oldptr = old;
entry->rcu_pending = 1;
/* write rcu_pending before calling the RCU callback */
smp_wmb();
call_rcu(&entry->rcu, free_old_closure);
remove_marker(name); /* Ignore busy error message */
+ ret = 0;
end:
mutex_unlock(&markers_mutex);
return ret;
diff --git a/kernel/module.c b/kernel/module.c
index 901cd6ac2f11..5d437bffd8dc 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1933,8 +1933,15 @@ static struct module *load_module(void __user *umod,
/* Set up license info based on the info section */
set_license(mod, get_modinfo(sechdrs, infoindex, "license"));
+ /*
+ * ndiswrapper is under GPL by itself, but loads proprietary modules.
+ * Don't use add_taint_module(), as it would prevent ndiswrapper from
+ * using GPL-only symbols it needs.
+ */
if (strcmp(mod->name, "ndiswrapper") == 0)
- add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
+ add_taint(TAINT_PROPRIETARY_MODULE);
+
+ /* driverloader was caught wrongly pretending to be under GPL */
if (strcmp(mod->name, "driverloader") == 0)
add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
@@ -2171,10 +2178,20 @@ sys_init_module(void __user *umod,
wake_up(&module_wq);
return ret;
}
+ if (ret > 0) {
+ printk(KERN_WARNING "%s: '%s'->init suspiciously returned %d, "
+ "it should follow 0/-E convention\n"
+ KERN_WARNING "%s: loading module anyway...\n",
+ __func__, mod->name, ret,
+ __func__);
+ dump_stack();
+ }
- /* Now it's a first class citizen! */
- mutex_lock(&module_mutex);
+ /* Now it's a first class citizen! Wake up anyone waiting for it. */
mod->state = MODULE_STATE_LIVE;
+ wake_up(&module_wq);
+
+ mutex_lock(&module_mutex);
/* Drop initial reference. */
module_put(mod);
unwind_remove_table(mod->unwind_info, 1);
@@ -2183,7 +2200,6 @@ sys_init_module(void __user *umod,
mod->init_size = 0;
mod->init_text_size = 0;
mutex_unlock(&module_mutex);
- wake_up(&module_wq);
return 0;
}
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 7c2118f9597f..f1d0b345c9ba 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -75,22 +75,15 @@ void refrigerator(void)
__set_current_state(save);
}
-static void fake_signal_wake_up(struct task_struct *p, int resume)
+static void fake_signal_wake_up(struct task_struct *p)
{
unsigned long flags;
spin_lock_irqsave(&p->sighand->siglock, flags);
- signal_wake_up(p, resume);
+ signal_wake_up(p, 0);
spin_unlock_irqrestore(&p->sighand->siglock, flags);
}
-static void send_fake_signal(struct task_struct *p)
-{
- if (task_is_stopped(p))
- force_sig_specific(SIGSTOP, p);
- fake_signal_wake_up(p, task_is_stopped(p));
-}
-
static int has_mm(struct task_struct *p)
{
return (p->mm && !(p->flags & PF_BORROWED_MM));
@@ -121,7 +114,7 @@ static int freeze_task(struct task_struct *p, int with_mm_only)
if (freezing(p)) {
if (has_mm(p)) {
if (!signal_pending(p))
- fake_signal_wake_up(p, 0);
+ fake_signal_wake_up(p);
} else {
if (with_mm_only)
ret = 0;
@@ -135,7 +128,7 @@ static int freeze_task(struct task_struct *p, int with_mm_only)
} else {
if (has_mm(p)) {
set_freeze_flag(p);
- send_fake_signal(p);
+ fake_signal_wake_up(p);
} else {
if (with_mm_only) {
ret = 0;
@@ -182,15 +175,17 @@ static int try_to_freeze_tasks(int freeze_user_space)
if (frozen(p) || !freezeable(p))
continue;
- if (task_is_traced(p) && frozen(p->parent)) {
- cancel_freezing(p);
- continue;
- }
-
if (!freeze_task(p, freeze_user_space))
continue;
- if (!freezer_should_skip(p))
+ /*
+ * Now that we've done set_freeze_flag, don't
+ * perturb a task in TASK_STOPPED or TASK_TRACED.
+ * It is "frozen enough". If the task does wake
+ * up, it will immediately call try_to_freeze.
+ */
+ if (!task_is_stopped_or_traced(p) &&
+ !freezer_should_skip(p))
todo++;
} while_each_thread(g, p);
read_unlock(&tasklist_lock);
diff --git a/kernel/printk.c b/kernel/printk.c
index bee36100f110..9adc2a473e6e 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -666,7 +666,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
}
/* Emit the output into the temporary buffer */
printed_len += vscnprintf(printk_buf + printed_len,
- sizeof(printk_buf), fmt, args);
+ sizeof(printk_buf) - printed_len, fmt, args);
/*
* Copy the output into log_buf. If the caller didn't provide
diff --git a/kernel/rcupreempt.c b/kernel/rcupreempt.c
index 987cfb7ade89..e9517014b57c 100644
--- a/kernel/rcupreempt.c
+++ b/kernel/rcupreempt.c
@@ -23,6 +23,10 @@
* to Suparna Bhattacharya for pushing me completely away
* from atomic instructions on the read side.
*
+ * - Added handling of Dynamic Ticks
+ * Copyright 2007 - Paul E. Mckenney <paulmck@us.ibm.com>
+ * - Steven Rostedt <srostedt@redhat.com>
+ *
* Papers: http://www.rdrop.com/users/paulmck/RCU
*
* Design Document: http://lwn.net/Articles/253651/
@@ -409,6 +413,212 @@ static void __rcu_advance_callbacks(struct rcu_data *rdp)
}
}
+#ifdef CONFIG_NO_HZ
+
+DEFINE_PER_CPU(long, dynticks_progress_counter) = 1;
+static DEFINE_PER_CPU(long, rcu_dyntick_snapshot);
+static DEFINE_PER_CPU(int, rcu_update_flag);
+
+/**
+ * rcu_irq_enter - Called from Hard irq handlers and NMI/SMI.
+ *
+ * If the CPU was idle with dynamic ticks active, this updates the
+ * dynticks_progress_counter to let the RCU handling know that the
+ * CPU is active.
+ */
+void rcu_irq_enter(void)
+{
+ int cpu = smp_processor_id();
+
+ if (per_cpu(rcu_update_flag, cpu))
+ per_cpu(rcu_update_flag, cpu)++;
+
+ /*
+ * Only update if we are coming from a stopped ticks mode
+ * (dynticks_progress_counter is even).
+ */
+ if (!in_interrupt() &&
+ (per_cpu(dynticks_progress_counter, cpu) & 0x1) == 0) {
+ /*
+ * The following might seem like we could have a race
+ * with NMI/SMIs. But this really isn't a problem.
+ * Here we do a read/modify/write, and the race happens
+ * when an NMI/SMI comes in after the read and before
+ * the write. But NMI/SMIs will increment this counter
+ * twice before returning, so the zero bit will not
+ * be corrupted by the NMI/SMI which is the most important
+ * part.
+ *
+ * The only thing is that we would bring back the counter
+ * to a postion that it was in during the NMI/SMI.
+ * But the zero bit would be set, so the rest of the
+ * counter would again be ignored.
+ *
+ * On return from the IRQ, the counter may have the zero
+ * bit be 0 and the counter the same as the return from
+ * the NMI/SMI. If the state machine was so unlucky to
+ * see that, it still doesn't matter, since all
+ * RCU read-side critical sections on this CPU would
+ * have already completed.
+ */
+ per_cpu(dynticks_progress_counter, cpu)++;
+ /*
+ * The following memory barrier ensures that any
+ * rcu_read_lock() primitives in the irq handler
+ * are seen by other CPUs to follow the above
+ * increment to dynticks_progress_counter. This is
+ * required in order for other CPUs to correctly
+ * determine when it is safe to advance the RCU
+ * grace-period state machine.
+ */
+ smp_mb(); /* see above block comment. */
+ /*
+ * Since we can't determine the dynamic tick mode from
+ * the dynticks_progress_counter after this routine,
+ * we use a second flag to acknowledge that we came
+ * from an idle state with ticks stopped.
+ */
+ per_cpu(rcu_update_flag, cpu)++;
+ /*
+ * If we take an NMI/SMI now, they will also increment
+ * the rcu_update_flag, and will not update the
+ * dynticks_progress_counter on exit. That is for
+ * this IRQ to do.
+ */
+ }
+}
+
+/**
+ * rcu_irq_exit - Called from exiting Hard irq context.
+ *
+ * If the CPU was idle with dynamic ticks active, update the
+ * dynticks_progress_counter to put let the RCU handling be
+ * aware that the CPU is going back to idle with no ticks.
+ */
+void rcu_irq_exit(void)
+{
+ int cpu = smp_processor_id();
+
+ /*
+ * rcu_update_flag is set if we interrupted the CPU
+ * when it was idle with ticks stopped.
+ * Once this occurs, we keep track of interrupt nesting
+ * because a NMI/SMI could also come in, and we still
+ * only want the IRQ that started the increment of the
+ * dynticks_progress_counter to be the one that modifies
+ * it on exit.
+ */
+ if (per_cpu(rcu_update_flag, cpu)) {
+ if (--per_cpu(rcu_update_flag, cpu))
+ return;
+
+ /* This must match the interrupt nesting */
+ WARN_ON(in_interrupt());
+
+ /*
+ * If an NMI/SMI happens now we are still
+ * protected by the dynticks_progress_counter being odd.
+ */
+
+ /*
+ * The following memory barrier ensures that any
+ * rcu_read_unlock() primitives in the irq handler
+ * are seen by other CPUs to preceed the following
+ * increment to dynticks_progress_counter. This
+ * is required in order for other CPUs to determine
+ * when it is safe to advance the RCU grace-period
+ * state machine.
+ */
+ smp_mb(); /* see above block comment. */
+ per_cpu(dynticks_progress_counter, cpu)++;
+ WARN_ON(per_cpu(dynticks_progress_counter, cpu) & 0x1);
+ }
+}
+
+static void dyntick_save_progress_counter(int cpu)
+{
+ per_cpu(rcu_dyntick_snapshot, cpu) =
+ per_cpu(dynticks_progress_counter, cpu);
+}
+
+static inline int
+rcu_try_flip_waitack_needed(int cpu)
+{
+ long curr;
+ long snap;
+
+ curr = per_cpu(dynticks_progress_counter, cpu);
+ snap = per_cpu(rcu_dyntick_snapshot, cpu);
+ smp_mb(); /* force ordering with cpu entering/leaving dynticks. */
+
+ /*
+ * If the CPU remained in dynticks mode for the entire time
+ * and didn't take any interrupts, NMIs, SMIs, or whatever,
+ * then it cannot be in the middle of an rcu_read_lock(), so
+ * the next rcu_read_lock() it executes must use the new value
+ * of the counter. So we can safely pretend that this CPU
+ * already acknowledged the counter.
+ */
+
+ if ((curr == snap) && ((curr & 0x1) == 0))
+ return 0;
+
+ /*
+ * If the CPU passed through or entered a dynticks idle phase with
+ * no active irq handlers, then, as above, we can safely pretend
+ * that this CPU already acknowledged the counter.
+ */
+
+ if ((curr - snap) > 2 || (snap & 0x1) == 0)
+ return 0;
+
+ /* We need this CPU to explicitly acknowledge the counter flip. */
+
+ return 1;
+}
+
+static inline int
+rcu_try_flip_waitmb_needed(int cpu)
+{
+ long curr;
+ long snap;
+
+ curr = per_cpu(dynticks_progress_counter, cpu);
+ snap = per_cpu(rcu_dyntick_snapshot, cpu);
+ smp_mb(); /* force ordering with cpu entering/leaving dynticks. */
+
+ /*
+ * If the CPU remained in dynticks mode for the entire time
+ * and didn't take any interrupts, NMIs, SMIs, or whatever,
+ * then it cannot have executed an RCU read-side critical section
+ * during that time, so there is no need for it to execute a
+ * memory barrier.
+ */
+
+ if ((curr == snap) && ((curr & 0x1) == 0))
+ return 0;
+
+ /*
+ * If the CPU either entered or exited an outermost interrupt,
+ * SMI, NMI, or whatever handler, then we know that it executed
+ * a memory barrier when doing so. So we don't need another one.
+ */
+ if (curr != snap)
+ return 0;
+
+ /* We need the CPU to execute a memory barrier. */
+
+ return 1;
+}
+
+#else /* !CONFIG_NO_HZ */
+
+# define dyntick_save_progress_counter(cpu) do { } while (0)
+# define rcu_try_flip_waitack_needed(cpu) (1)
+# define rcu_try_flip_waitmb_needed(cpu) (1)
+
+#endif /* CONFIG_NO_HZ */
+
/*
* Get here when RCU is idle. Decide whether we need to
* move out of idle state, and return non-zero if so.
@@ -447,8 +657,10 @@ rcu_try_flip_idle(void)
/* Now ask each CPU for acknowledgement of the flip. */
- for_each_cpu_mask(cpu, rcu_cpu_online_map)
+ for_each_cpu_mask(cpu, rcu_cpu_online_map) {
per_cpu(rcu_flip_flag, cpu) = rcu_flipped;
+ dyntick_save_progress_counter(cpu);
+ }
return 1;
}
@@ -464,7 +676,8 @@ rcu_try_flip_waitack(void)
RCU_TRACE_ME(rcupreempt_trace_try_flip_a1);
for_each_cpu_mask(cpu, rcu_cpu_online_map)
- if (per_cpu(rcu_flip_flag, cpu) != rcu_flip_seen) {
+ if (rcu_try_flip_waitack_needed(cpu) &&
+ per_cpu(rcu_flip_flag, cpu) != rcu_flip_seen) {
RCU_TRACE_ME(rcupreempt_trace_try_flip_ae1);
return 0;
}
@@ -509,8 +722,10 @@ rcu_try_flip_waitzero(void)
smp_mb(); /* ^^^^^^^^^^^^ */
/* Call for a memory barrier from each CPU. */
- for_each_cpu_mask(cpu, rcu_cpu_online_map)
+ for_each_cpu_mask(cpu, rcu_cpu_online_map) {
per_cpu(rcu_mb_flag, cpu) = rcu_mb_needed;
+ dyntick_save_progress_counter(cpu);
+ }
RCU_TRACE_ME(rcupreempt_trace_try_flip_z2);
return 1;
@@ -528,7 +743,8 @@ rcu_try_flip_waitmb(void)
RCU_TRACE_ME(rcupreempt_trace_try_flip_m1);
for_each_cpu_mask(cpu, rcu_cpu_online_map)
- if (per_cpu(rcu_mb_flag, cpu) != rcu_mb_done) {
+ if (rcu_try_flip_waitmb_needed(cpu) &&
+ per_cpu(rcu_mb_flag, cpu) != rcu_mb_done) {
RCU_TRACE_ME(rcupreempt_trace_try_flip_me1);
return 0;
}
@@ -702,8 +918,9 @@ void rcu_offline_cpu(int cpu)
* fix.
*/
+ local_irq_save(flags);
rdp = RCU_DATA_ME();
- spin_lock_irqsave(&rdp->lock, flags);
+ spin_lock(&rdp->lock);
*rdp->nexttail = list;
if (list)
rdp->nexttail = tail;
@@ -735,9 +952,11 @@ static void rcu_process_callbacks(struct softirq_action *unused)
{
unsigned long flags;
struct rcu_head *next, *list;
- struct rcu_data *rdp = RCU_DATA_ME();
+ struct rcu_data *rdp;
- spin_lock_irqsave(&rdp->lock, flags);
+ local_irq_save(flags);
+ rdp = RCU_DATA_ME();
+ spin_lock(&rdp->lock);
list = rdp->donelist;
if (list == NULL) {
spin_unlock_irqrestore(&rdp->lock, flags);
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index 16cbec2d5d60..efbfc0fc232f 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -113,6 +113,7 @@ ssize_t res_counter_write(struct res_counter *counter, int member,
ret = -EINVAL;
+ strstrip(buf);
if (write_strategy) {
if (write_strategy(buf, &tmp)) {
goto out_free;
diff --git a/kernel/sched.c b/kernel/sched.c
index b387a8de26a5..1cb53fb1fe3d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -174,41 +174,6 @@ struct task_group {
struct sched_entity **se;
/* runqueue "owned" by this group on each cpu */
struct cfs_rq **cfs_rq;
-
- /*
- * shares assigned to a task group governs how much of cpu bandwidth
- * is allocated to the group. The more shares a group has, the more is
- * the cpu bandwidth allocated to it.
- *
- * For ex, lets say that there are three task groups, A, B and C which
- * have been assigned shares 1000, 2000 and 3000 respectively. Then,
- * cpu bandwidth allocated by the scheduler to task groups A, B and C
- * should be:
- *
- * Bw(A) = 1000/(1000+2000+3000) * 100 = 16.66%
- * Bw(B) = 2000/(1000+2000+3000) * 100 = 33.33%
- * Bw(C) = 3000/(1000+2000+3000) * 100 = 50%
- *
- * The weight assigned to a task group's schedulable entities on every
- * cpu (task_group.se[a_cpu]->load.weight) is derived from the task
- * group's shares. For ex: lets say that task group A has been
- * assigned shares of 1000 and there are two CPUs in a system. Then,
- *
- * tg_A->se[0]->load.weight = tg_A->se[1]->load.weight = 1000;
- *
- * Note: It's not necessary that each of a task's group schedulable
- * entity have the same weight on all CPUs. If the group
- * has 2 of its tasks on CPU0 and 1 task on CPU1, then a
- * better distribution of weight could be:
- *
- * tg_A->se[0]->load.weight = 2/3 * 2000 = 1333
- * tg_A->se[1]->load.weight = 1/2 * 2000 = 667
- *
- * rebalance_shares() is responsible for distributing the shares of a
- * task groups like this among the group's schedulable entities across
- * cpus.
- *
- */
unsigned long shares;
#endif
@@ -250,22 +215,12 @@ static DEFINE_SPINLOCK(task_group_lock);
static DEFINE_MUTEX(doms_cur_mutex);
#ifdef CONFIG_FAIR_GROUP_SCHED
-#ifdef CONFIG_SMP
-/* kernel thread that runs rebalance_shares() periodically */
-static struct task_struct *lb_monitor_task;
-static int load_balance_monitor(void *unused);
-#endif
-
-static void set_se_shares(struct sched_entity *se, unsigned long shares);
-
#ifdef CONFIG_USER_SCHED
# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
#else
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
#endif
-#define MIN_GROUP_SHARES 2
-
static int init_task_group_load = INIT_TASK_GROUP_LOAD;
#endif
@@ -668,6 +623,8 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32;
*/
unsigned int sysctl_sched_rt_period = 1000000;
+static __read_mostly int scheduler_running;
+
/*
* part of the period that we allow rt tasks to run in us.
* default: 0.95s
@@ -689,14 +646,16 @@ unsigned long long cpu_clock(int cpu)
unsigned long flags;
struct rq *rq;
- local_irq_save(flags);
- rq = cpu_rq(cpu);
/*
* Only call sched_clock() if the scheduler has already been
* initialized (some code might call cpu_clock() very early):
*/
- if (rq->idle)
- update_rq_clock(rq);
+ if (unlikely(!scheduler_running))
+ return 0;
+
+ local_irq_save(flags);
+ rq = cpu_rq(cpu);
+ update_rq_clock(rq);
now = rq->clock;
local_irq_restore(flags);
@@ -1241,16 +1200,6 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime);
static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
#endif
-static inline void inc_cpu_load(struct rq *rq, unsigned long load)
-{
- update_load_add(&rq->load, load);
-}
-
-static inline void dec_cpu_load(struct rq *rq, unsigned long load)
-{
- update_load_sub(&rq->load, load);
-}
-
#ifdef CONFIG_SMP
static unsigned long source_load(int cpu, int type);
static unsigned long target_load(int cpu, int type);
@@ -1268,14 +1217,26 @@ static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
#define sched_class_highest (&rt_sched_class)
-static void inc_nr_running(struct rq *rq)
+static inline void inc_load(struct rq *rq, const struct task_struct *p)
+{
+ update_load_add(&rq->load, p->se.load.weight);
+}
+
+static inline void dec_load(struct rq *rq, const struct task_struct *p)
+{
+ update_load_sub(&rq->load, p->se.load.weight);
+}
+
+static void inc_nr_running(struct task_struct *p, struct rq *rq)
{
rq->nr_running++;
+ inc_load(rq, p);
}
-static void dec_nr_running(struct rq *rq)
+static void dec_nr_running(struct task_struct *p, struct rq *rq)
{
rq->nr_running--;
+ dec_load(rq, p);
}
static void set_load_weight(struct task_struct *p)
@@ -1367,7 +1328,7 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
rq->nr_uninterruptible--;
enqueue_task(rq, p, wakeup);
- inc_nr_running(rq);
+ inc_nr_running(p, rq);
}
/*
@@ -1379,7 +1340,7 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
rq->nr_uninterruptible++;
dequeue_task(rq, p, sleep);
- dec_nr_running(rq);
+ dec_nr_running(p, rq);
}
/**
@@ -2019,7 +1980,7 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
* management (if any):
*/
p->sched_class->task_new(rq, p);
- inc_nr_running(rq);
+ inc_nr_running(p, rq);
}
check_preempt_curr(rq, p);
#ifdef CONFIG_SMP
@@ -3885,7 +3846,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev)
asmlinkage void __sched schedule(void)
{
struct task_struct *prev, *next;
- long *switch_count;
+ unsigned long *switch_count;
struct rq *rq;
int cpu;
@@ -4358,8 +4319,10 @@ void set_user_nice(struct task_struct *p, long nice)
goto out_unlock;
}
on_rq = p->se.on_rq;
- if (on_rq)
+ if (on_rq) {
dequeue_task(rq, p, 0);
+ dec_load(rq, p);
+ }
p->static_prio = NICE_TO_PRIO(nice);
set_load_weight(p);
@@ -4369,6 +4332,7 @@ void set_user_nice(struct task_struct *p, long nice)
if (on_rq) {
enqueue_task(rq, p, 0);
+ inc_load(rq, p);
/*
* If the task increased its priority or is running and
* lowered its priority, then reschedule its CPU:
@@ -4458,7 +4422,7 @@ int task_nice(const struct task_struct *p)
{
return TASK_NICE(p);
}
-EXPORT_SYMBOL_GPL(task_nice);
+EXPORT_SYMBOL(task_nice);
/**
* idle_cpu - is a given cpu idle currently?
@@ -5136,7 +5100,7 @@ long sys_sched_rr_get_interval(pid_t pid, struct timespec __user *interval)
time_slice = 0;
if (p->policy == SCHED_RR) {
time_slice = DEF_TIMESLICE;
- } else {
+ } else if (p->policy != SCHED_FIFO) {
struct sched_entity *se = &p->se;
unsigned long flags;
struct rq *rq;
@@ -5917,7 +5881,8 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
spin_unlock_irq(&rq->lock);
break;
- case CPU_DOWN_PREPARE:
+ case CPU_DYING:
+ case CPU_DYING_FROZEN:
/* Update our root-domain */
rq = cpu_rq(cpu);
spin_lock_irqsave(&rq->lock, flags);
@@ -7083,21 +7048,6 @@ void __init sched_init_smp(void)
if (set_cpus_allowed(current, non_isolated_cpus) < 0)
BUG();
sched_init_granularity();
-
-#ifdef CONFIG_FAIR_GROUP_SCHED
- if (nr_cpu_ids == 1)
- return;
-
- lb_monitor_task = kthread_create(load_balance_monitor, NULL,
- "group_balance");
- if (!IS_ERR(lb_monitor_task)) {
- lb_monitor_task->flags |= PF_NOFREEZE;
- wake_up_process(lb_monitor_task);
- } else {
- printk(KERN_ERR "Could not create load balance monitor thread"
- "(error = %ld) \n", PTR_ERR(lb_monitor_task));
- }
-#endif
}
#else
void __init sched_init_smp(void)
@@ -7284,6 +7234,8 @@ void __init sched_init(void)
* During early bootup we pretend to be a normal task:
*/
current->sched_class = &fair_sched_class;
+
+ scheduler_running = 1;
}
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
@@ -7418,157 +7370,6 @@ void set_curr_task(int cpu, struct task_struct *p)
#ifdef CONFIG_GROUP_SCHED
-#if defined CONFIG_FAIR_GROUP_SCHED && defined CONFIG_SMP
-/*
- * distribute shares of all task groups among their schedulable entities,
- * to reflect load distribution across cpus.
- */
-static int rebalance_shares(struct sched_domain *sd, int this_cpu)
-{
- struct cfs_rq *cfs_rq;
- struct rq *rq = cpu_rq(this_cpu);
- cpumask_t sdspan = sd->span;
- int balanced = 1;
-
- /* Walk thr' all the task groups that we have */
- for_each_leaf_cfs_rq(rq, cfs_rq) {
- int i;
- unsigned long total_load = 0, total_shares;
- struct task_group *tg = cfs_rq->tg;
-
- /* Gather total task load of this group across cpus */
- for_each_cpu_mask(i, sdspan)
- total_load += tg->cfs_rq[i]->load.weight;
-
- /* Nothing to do if this group has no load */
- if (!total_load)
- continue;
-
- /*
- * tg->shares represents the number of cpu shares the task group
- * is eligible to hold on a single cpu. On N cpus, it is
- * eligible to hold (N * tg->shares) number of cpu shares.
- */
- total_shares = tg->shares * cpus_weight(sdspan);
-
- /*
- * redistribute total_shares across cpus as per the task load
- * distribution.
- */
- for_each_cpu_mask(i, sdspan) {
- unsigned long local_load, local_shares;
-
- local_load = tg->cfs_rq[i]->load.weight;
- local_shares = (local_load * total_shares) / total_load;
- if (!local_shares)
- local_shares = MIN_GROUP_SHARES;
- if (local_shares == tg->se[i]->load.weight)
- continue;
-
- spin_lock_irq(&cpu_rq(i)->lock);
- set_se_shares(tg->se[i], local_shares);
- spin_unlock_irq(&cpu_rq(i)->lock);
- balanced = 0;
- }
- }
-
- return balanced;
-}
-
-/*
- * How frequently should we rebalance_shares() across cpus?
- *
- * The more frequently we rebalance shares, the more accurate is the fairness
- * of cpu bandwidth distribution between task groups. However higher frequency
- * also implies increased scheduling overhead.
- *
- * sysctl_sched_min_bal_int_shares represents the minimum interval between
- * consecutive calls to rebalance_shares() in the same sched domain.
- *
- * sysctl_sched_max_bal_int_shares represents the maximum interval between
- * consecutive calls to rebalance_shares() in the same sched domain.
- *
- * These settings allows for the appropriate trade-off between accuracy of
- * fairness and the associated overhead.
- *
- */
-
-/* default: 8ms, units: milliseconds */
-const_debug unsigned int sysctl_sched_min_bal_int_shares = 8;
-
-/* default: 128ms, units: milliseconds */
-const_debug unsigned int sysctl_sched_max_bal_int_shares = 128;
-
-/* kernel thread that runs rebalance_shares() periodically */
-static int load_balance_monitor(void *unused)
-{
- unsigned int timeout = sysctl_sched_min_bal_int_shares;
- struct sched_param schedparm;
- int ret;
-
- /*
- * We don't want this thread's execution to be limited by the shares
- * assigned to default group (init_task_group). Hence make it run
- * as a SCHED_RR RT task at the lowest priority.
- */
- schedparm.sched_priority = 1;
- ret = sched_setscheduler(current, SCHED_RR, &schedparm);
- if (ret)
- printk(KERN_ERR "Couldn't set SCHED_RR policy for load balance"
- " monitor thread (error = %d) \n", ret);
-
- while (!kthread_should_stop()) {
- int i, cpu, balanced = 1;
-
- /* Prevent cpus going down or coming up */
- get_online_cpus();
- /* lockout changes to doms_cur[] array */
- lock_doms_cur();
- /*
- * Enter a rcu read-side critical section to safely walk rq->sd
- * chain on various cpus and to walk task group list
- * (rq->leaf_cfs_rq_list) in rebalance_shares().
- */
- rcu_read_lock();
-
- for (i = 0; i < ndoms_cur; i++) {
- cpumask_t cpumap = doms_cur[i];
- struct sched_domain *sd = NULL, *sd_prev = NULL;
-
- cpu = first_cpu(cpumap);
-
- /* Find the highest domain at which to balance shares */
- for_each_domain(cpu, sd) {
- if (!(sd->flags & SD_LOAD_BALANCE))
- continue;
- sd_prev = sd;
- }
-
- sd = sd_prev;
- /* sd == NULL? No load balance reqd in this domain */
- if (!sd)
- continue;
-
- balanced &= rebalance_shares(sd, cpu);
- }
-
- rcu_read_unlock();
-
- unlock_doms_cur();
- put_online_cpus();
-
- if (!balanced)
- timeout = sysctl_sched_min_bal_int_shares;
- else if (timeout < sysctl_sched_max_bal_int_shares)
- timeout *= 2;
-
- msleep_interruptible(timeout);
- }
-
- return 0;
-}
-#endif /* CONFIG_SMP */
-
#ifdef CONFIG_FAIR_GROUP_SCHED
static void free_fair_sched_group(struct task_group *tg)
{
@@ -7825,6 +7626,11 @@ void sched_move_task(struct task_struct *tsk)
set_task_rq(tsk, task_cpu(tsk));
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ if (tsk->sched_class->moved_group)
+ tsk->sched_class->moved_group(tsk);
+#endif
+
if (on_rq) {
if (unlikely(running))
tsk->sched_class->set_curr_task(rq);
@@ -7835,29 +7641,25 @@ void sched_move_task(struct task_struct *tsk)
}
#ifdef CONFIG_FAIR_GROUP_SCHED
-/* rq->lock to be locked by caller */
static void set_se_shares(struct sched_entity *se, unsigned long shares)
{
struct cfs_rq *cfs_rq = se->cfs_rq;
struct rq *rq = cfs_rq->rq;
int on_rq;
- if (!shares)
- shares = MIN_GROUP_SHARES;
+ spin_lock_irq(&rq->lock);
on_rq = se->on_rq;
- if (on_rq) {
+ if (on_rq)
dequeue_entity(cfs_rq, se, 0);
- dec_cpu_load(rq, se->load.weight);
- }
se->load.weight = shares;
se->load.inv_weight = div64_64((1ULL<<32), shares);
- if (on_rq) {
+ if (on_rq)
enqueue_entity(cfs_rq, se, 0);
- inc_cpu_load(rq, se->load.weight);
- }
+
+ spin_unlock_irq(&rq->lock);
}
static DEFINE_MUTEX(shares_mutex);
@@ -7867,18 +7669,18 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
int i;
unsigned long flags;
+ /*
+ * A weight of 0 or 1 can cause arithmetics problems.
+ * (The default weight is 1024 - so there's no practical
+ * limitation from this.)
+ */
+ if (shares < 2)
+ shares = 2;
+
mutex_lock(&shares_mutex);
if (tg->shares == shares)
goto done;
- if (shares < MIN_GROUP_SHARES)
- shares = MIN_GROUP_SHARES;
-
- /*
- * Prevent any load balance activity (rebalance_shares,
- * load_balance_fair) from referring to this group first,
- * by taking it off the rq->leaf_cfs_rq_list on each cpu.
- */
spin_lock_irqsave(&task_group_lock, flags);
for_each_possible_cpu(i)
unregister_fair_sched_group(tg, i);
@@ -7892,11 +7694,8 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
* w/o tripping rebalance_share or load_balance_fair.
*/
tg->shares = shares;
- for_each_possible_cpu(i) {
- spin_lock_irq(&cpu_rq(i)->lock);
+ for_each_possible_cpu(i)
set_se_shares(tg->se[i], shares);
- spin_unlock_irq(&cpu_rq(i)->lock);
- }
/*
* Enable load balance activity on this group, by inserting it back on
@@ -7928,9 +7727,7 @@ static unsigned long to_ratio(u64 period, u64 runtime)
if (runtime == RUNTIME_INF)
return 1ULL << 16;
- runtime *= (1ULL << 16);
- div64_64(runtime, period);
- return runtime;
+ return div64_64(runtime << 16, period);
}
static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
@@ -7954,25 +7751,40 @@ static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
return total + to_ratio(period, runtime) < global_ratio;
}
+/* Must be called with tasklist_lock held */
+static inline int tg_has_rt_tasks(struct task_group *tg)
+{
+ struct task_struct *g, *p;
+ do_each_thread(g, p) {
+ if (rt_task(p) && rt_rq_of_se(&p->rt)->tg == tg)
+ return 1;
+ } while_each_thread(g, p);
+ return 0;
+}
+
int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us)
{
u64 rt_runtime, rt_period;
int err = 0;
- rt_period = sysctl_sched_rt_period * NSEC_PER_USEC;
+ rt_period = (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
rt_runtime = (u64)rt_runtime_us * NSEC_PER_USEC;
if (rt_runtime_us == -1)
- rt_runtime = rt_period;
+ rt_runtime = RUNTIME_INF;
mutex_lock(&rt_constraints_mutex);
+ read_lock(&tasklist_lock);
+ if (rt_runtime_us == 0 && tg_has_rt_tasks(tg)) {
+ err = -EBUSY;
+ goto unlock;
+ }
if (!__rt_schedulable(tg, rt_period, rt_runtime)) {
err = -EINVAL;
goto unlock;
}
- if (rt_runtime_us == -1)
- rt_runtime = RUNTIME_INF;
tg->rt_runtime = rt_runtime;
unlock:
+ read_unlock(&tasklist_lock);
mutex_unlock(&rt_constraints_mutex);
return err;
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 6c091d6e159d..e2a530515619 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -202,17 +202,12 @@ static struct sched_entity *__pick_next_entity(struct cfs_rq *cfs_rq)
static inline struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
{
- struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
- struct sched_entity *se = NULL;
- struct rb_node *parent;
+ struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
- while (*link) {
- parent = *link;
- se = rb_entry(parent, struct sched_entity, run_node);
- link = &parent->rb_right;
- }
+ if (!last)
+ return NULL;
- return se;
+ return rb_entry(last, struct sched_entity, run_node);
}
/**************************************************************
@@ -732,8 +727,6 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se)
return se->parent;
}
-#define GROUP_IMBALANCE_PCT 20
-
#else /* CONFIG_FAIR_GROUP_SCHED */
#define for_each_sched_entity(se) \
@@ -824,26 +817,15 @@ hrtick_start_fair(struct rq *rq, struct task_struct *p)
static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup)
{
struct cfs_rq *cfs_rq;
- struct sched_entity *se = &p->se,
- *topse = NULL; /* Highest schedulable entity */
- int incload = 1;
+ struct sched_entity *se = &p->se;
for_each_sched_entity(se) {
- topse = se;
- if (se->on_rq) {
- incload = 0;
+ if (se->on_rq)
break;
- }
cfs_rq = cfs_rq_of(se);
enqueue_entity(cfs_rq, se, wakeup);
wakeup = 1;
}
- /* Increment cpu load if we just enqueued the first task of a group on
- * 'rq->cpu'. 'topse' represents the group to which task 'p' belongs
- * at the highest grouping level.
- */
- if (incload)
- inc_cpu_load(rq, topse->load.weight);
hrtick_start_fair(rq, rq->curr);
}
@@ -856,28 +838,16 @@ static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup)
static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int sleep)
{
struct cfs_rq *cfs_rq;
- struct sched_entity *se = &p->se,
- *topse = NULL; /* Highest schedulable entity */
- int decload = 1;
+ struct sched_entity *se = &p->se;
for_each_sched_entity(se) {
- topse = se;
cfs_rq = cfs_rq_of(se);
dequeue_entity(cfs_rq, se, sleep);
/* Don't dequeue parent if it has other entities besides us */
- if (cfs_rq->load.weight) {
- if (parent_entity(se))
- decload = 0;
+ if (cfs_rq->load.weight)
break;
- }
sleep = 1;
}
- /* Decrement cpu load if we just dequeued the last task of a group on
- * 'rq->cpu'. 'topse' represents the group to which task 'p' belongs
- * at the highest grouping level.
- */
- if (decload)
- dec_cpu_load(rq, topse->load.weight);
hrtick_start_fair(rq, rq->curr);
}
@@ -1191,6 +1161,25 @@ static struct task_struct *load_balance_next_fair(void *arg)
return __load_balance_iterator(cfs_rq, cfs_rq->rb_load_balance_curr);
}
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static int cfs_rq_best_prio(struct cfs_rq *cfs_rq)
+{
+ struct sched_entity *curr;
+ struct task_struct *p;
+
+ if (!cfs_rq->nr_running || !first_fair(cfs_rq))
+ return MAX_PRIO;
+
+ curr = cfs_rq->curr;
+ if (!curr)
+ curr = __pick_next_entity(cfs_rq);
+
+ p = task_of(curr);
+
+ return p->prio;
+}
+#endif
+
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
@@ -1200,45 +1189,28 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
struct cfs_rq *busy_cfs_rq;
long rem_load_move = max_load_move;
struct rq_iterator cfs_rq_iterator;
- unsigned long load_moved;
cfs_rq_iterator.start = load_balance_start_fair;
cfs_rq_iterator.next = load_balance_next_fair;
for_each_leaf_cfs_rq(busiest, busy_cfs_rq) {
#ifdef CONFIG_FAIR_GROUP_SCHED
- struct cfs_rq *this_cfs_rq = busy_cfs_rq->tg->cfs_rq[this_cpu];
- unsigned long maxload, task_load, group_weight;
- unsigned long thisload, per_task_load;
- struct sched_entity *se = busy_cfs_rq->tg->se[busiest->cpu];
-
- task_load = busy_cfs_rq->load.weight;
- group_weight = se->load.weight;
+ struct cfs_rq *this_cfs_rq;
+ long imbalance;
+ unsigned long maxload;
- /*
- * 'group_weight' is contributed by tasks of total weight
- * 'task_load'. To move 'rem_load_move' worth of weight only,
- * we need to move a maximum task load of:
- *
- * maxload = (remload / group_weight) * task_load;
- */
- maxload = (rem_load_move * task_load) / group_weight;
+ this_cfs_rq = cpu_cfs_rq(busy_cfs_rq, this_cpu);
- if (!maxload || !task_load)
+ imbalance = busy_cfs_rq->load.weight - this_cfs_rq->load.weight;
+ /* Don't pull if this_cfs_rq has more load than busy_cfs_rq */
+ if (imbalance <= 0)
continue;
- per_task_load = task_load / busy_cfs_rq->nr_running;
- /*
- * balance_tasks will try to forcibly move atleast one task if
- * possible (because of SCHED_LOAD_SCALE_FUZZ). Avoid that if
- * maxload is less than GROUP_IMBALANCE_FUZZ% the per_task_load.
- */
- if (100 * maxload < GROUP_IMBALANCE_PCT * per_task_load)
- continue;
+ /* Don't pull more than imbalance/2 */
+ imbalance /= 2;
+ maxload = min(rem_load_move, imbalance);
- /* Disable priority-based load balance */
- *this_best_prio = 0;
- thisload = this_cfs_rq->load.weight;
+ *this_best_prio = cfs_rq_best_prio(this_cfs_rq);
#else
# define maxload rem_load_move
#endif
@@ -1247,33 +1219,11 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
* load_balance_[start|next]_fair iterators
*/
cfs_rq_iterator.arg = busy_cfs_rq;
- load_moved = balance_tasks(this_rq, this_cpu, busiest,
+ rem_load_move -= balance_tasks(this_rq, this_cpu, busiest,
maxload, sd, idle, all_pinned,
this_best_prio,
&cfs_rq_iterator);
-#ifdef CONFIG_FAIR_GROUP_SCHED
- /*
- * load_moved holds the task load that was moved. The
- * effective (group) weight moved would be:
- * load_moved_eff = load_moved/task_load * group_weight;
- */
- load_moved = (group_weight * load_moved) / task_load;
-
- /* Adjust shares on both cpus to reflect load_moved */
- group_weight -= load_moved;
- set_se_shares(se, group_weight);
-
- se = busy_cfs_rq->tg->se[this_cpu];
- if (!thisload)
- group_weight = load_moved;
- else
- group_weight = se->load.weight + load_moved;
- set_se_shares(se, group_weight);
-#endif
-
- rem_load_move -= load_moved;
-
if (rem_load_move <= 0)
break;
}
@@ -1403,6 +1353,16 @@ static void set_curr_task_fair(struct rq *rq)
set_next_entity(cfs_rq_of(se), se);
}
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void moved_group_fair(struct task_struct *p)
+{
+ struct cfs_rq *cfs_rq = task_cfs_rq(p);
+
+ update_curr(cfs_rq);
+ place_entity(cfs_rq, &p->se, 1);
+}
+#endif
+
/*
* All the scheduling class methods:
*/
@@ -1431,6 +1391,10 @@ static const struct sched_class fair_sched_class = {
.prio_changed = prio_changed_fair,
.switched_to = switched_to_fair,
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ .moved_group = moved_group_fair,
+#endif
};
#ifdef CONFIG_SCHED_DEBUG
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index f54792b175b2..0a6d2e516420 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -393,8 +393,6 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
*/
for_each_sched_rt_entity(rt_se)
enqueue_rt_entity(rt_se);
-
- inc_cpu_load(rq, p->se.load.weight);
}
static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
@@ -414,8 +412,6 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
if (rt_rq && rt_rq->rt_nr_running)
enqueue_rt_entity(rt_se);
}
-
- dec_cpu_load(rq, p->se.load.weight);
}
/*
@@ -1111,9 +1107,11 @@ static void prio_changed_rt(struct rq *rq, struct task_struct *p,
pull_rt_task(rq);
/*
* If there's a higher priority task waiting to run
- * then reschedule.
+ * then reschedule. Note, the above pull_rt_task
+ * can release the rq lock and p could migrate.
+ * Only reschedule if p is still on the same runqueue.
*/
- if (p->prio > rq->rt.highest_prio)
+ if (p->prio > rq->rt.highest_prio && rq->curr == p)
resched_task(p);
#else
/* For UP simply resched on drop of prio */
diff --git a/kernel/signal.c b/kernel/signal.c
index 84917fe507f7..6af1210092c3 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1623,7 +1623,6 @@ static void ptrace_stop(int exit_code, int clear_code, siginfo_t *info)
/* Let the debugger run. */
__set_current_state(TASK_TRACED);
spin_unlock_irq(&current->sighand->siglock);
- try_to_freeze();
read_lock(&tasklist_lock);
if (!unlikely(killed) && may_ptrace_stop()) {
do_notify_parent_cldstop(current, CLD_TRAPPED);
@@ -1641,6 +1640,13 @@ static void ptrace_stop(int exit_code, int clear_code, siginfo_t *info)
}
/*
+ * While in TASK_TRACED, we were considered "frozen enough".
+ * Now that we woke up, it's crucial if we're supposed to be
+ * frozen that we freeze now before running anything substantial.
+ */
+ try_to_freeze();
+
+ /*
* We are back. Now reacquire the siglock before touching
* last_siginfo, so that we are sure to have synchronized with
* any signal-sending on another CPU that wants to examine it.
@@ -1757,9 +1763,15 @@ int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka,
sigset_t *mask = &current->blocked;
int signr = 0;
+relock:
+ /*
+ * We'll jump back here after any time we were stopped in TASK_STOPPED.
+ * While in TASK_STOPPED, we were considered "frozen enough".
+ * Now that we woke up, it's crucial if we're supposed to be
+ * frozen that we freeze now before running anything substantial.
+ */
try_to_freeze();
-relock:
spin_lock_irq(&current->sighand->siglock);
for (;;) {
struct k_sigaction *ka;
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 5b3aea5f471e..31e9f2a47928 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -313,6 +313,7 @@ void irq_exit(void)
/* Make sure that timer wheel updates are propagated */
if (!in_interrupt() && idle_cpu(smp_processor_id()) && !need_resched())
tick_nohz_stop_sched_tick();
+ rcu_irq_exit();
#endif
preempt_enable_no_resched();
}
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 7c2da88db4ed..01b6522fd92b 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -216,26 +216,27 @@ static int watchdog(void *__bind_cpu)
/* initialize timestamp */
touch_softlockup_watchdog();
+ set_current_state(TASK_INTERRUPTIBLE);
/*
* Run briefly once per second to reset the softlockup timestamp.
* If this gets delayed for more than 60 seconds then the
* debug-printout triggers in softlockup_tick().
*/
while (!kthread_should_stop()) {
- set_current_state(TASK_INTERRUPTIBLE);
touch_softlockup_watchdog();
schedule();
if (kthread_should_stop())
break;
- if (this_cpu != check_cpu)
- continue;
-
- if (sysctl_hung_task_timeout_secs)
- check_hung_uninterruptible_tasks(this_cpu);
+ if (this_cpu == check_cpu) {
+ if (sysctl_hung_task_timeout_secs)
+ check_hung_uninterruptible_tasks(this_cpu);
+ }
+ set_current_state(TASK_INTERRUPTIBLE);
}
+ __set_current_state(TASK_RUNNING);
return 0;
}
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 8b7e95411795..b2a2d6889bab 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -311,24 +311,6 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
-#if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP)
- {
- .ctl_name = CTL_UNNUMBERED,
- .procname = "sched_min_bal_int_shares",
- .data = &sysctl_sched_min_bal_int_shares,
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = &proc_dointvec,
- },
- {
- .ctl_name = CTL_UNNUMBERED,
- .procname = "sched_max_bal_int_shares",
- .data = &sysctl_sched_max_bal_int_shares,
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = &proc_dointvec,
- },
-#endif
#endif
{
.ctl_name = CTL_UNNUMBERED,
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index c88b5910e7ab..5fd9b9469770 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -42,12 +42,13 @@ long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */
long time_freq; /* frequency offset (scaled ppm)*/
static long time_reftime; /* time at last adjustment (s) */
long time_adjust;
+static long ntp_tick_adj;
static void ntp_update_frequency(void)
{
u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
<< TICK_LENGTH_SHIFT;
- second_length += (s64)CLOCK_TICK_ADJUST << TICK_LENGTH_SHIFT;
+ second_length += (s64)ntp_tick_adj << TICK_LENGTH_SHIFT;
second_length += (s64)time_freq << (TICK_LENGTH_SHIFT - SHIFT_NSEC);
tick_length_base = second_length;
@@ -342,14 +343,16 @@ int do_adjtimex(struct timex *txc)
freq_adj = shift_right(freq_adj, time_constant * 2 +
(SHIFT_PLL + 2) * 2 - SHIFT_NSEC);
if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) {
+ u64 utemp64;
temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL);
if (time_offset < 0) {
- temp64 = -temp64;
- do_div(temp64, mtemp);
- freq_adj -= temp64;
+ utemp64 = -temp64;
+ do_div(utemp64, mtemp);
+ freq_adj -= utemp64;
} else {
- do_div(temp64, mtemp);
- freq_adj += temp64;
+ utemp64 = temp64;
+ do_div(utemp64, mtemp);
+ freq_adj += utemp64;
}
}
freq_adj += time_freq;
@@ -400,3 +403,11 @@ leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0)
notify_cmos_timer();
return(result);
}
+
+static int __init ntp_tick_adj_setup(char *str)
+{
+ ntp_tick_adj = simple_strtol(str, NULL, 0);
+ return 1;
+}
+
+__setup("ntp_tick_adj=", ntp_tick_adj_setup);
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index fa9bb73dbdb4..686da821d376 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -282,6 +282,7 @@ void tick_nohz_stop_sched_tick(void)
ts->idle_tick = ts->sched_timer.expires;
ts->tick_stopped = 1;
ts->idle_jiffies = last_jiffies;
+ rcu_enter_nohz();
}
/*
@@ -375,6 +376,8 @@ void tick_nohz_restart_sched_tick(void)
return;
}
+ rcu_exit_nohz();
+
/* Update jiffies first */
select_nohz_load_balancer(0);
now = ktime_get();
@@ -637,7 +640,7 @@ void tick_cancel_sched_timer(int cpu)
if (ts->sched_timer.base)
hrtimer_cancel(&ts->sched_timer);
- ts->tick_stopped = 0;
+
ts->nohz_mode = NOHZ_MODE_INACTIVE;
}
#endif /* HIGH_RES_TIMERS */
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 1af9fb050fe2..671af612b768 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -187,8 +187,7 @@ static void change_clocksource(void)
clock->error = 0;
clock->xtime_nsec = 0;
- clocksource_calculate_interval(clock,
- (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT));
+ clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
tick_clock_notify();
@@ -245,8 +244,7 @@ void __init timekeeping_init(void)
ntp_clear();
clock = clocksource_get_next();
- clocksource_calculate_interval(clock,
- (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT));
+ clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
clock->cycle_last = clocksource_read(clock);
xtime.tv_sec = sec;
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-18 22:35:14 +0000