cpu_relax();
else {
local_irq_disable();
- if (!need_resched()) {
- timer_dyn_reprogram();
+ if (!need_resched())
arch_idle();
- }
local_irq_enable();
}
}
if (!idle)
idle = default_idle;
leds_event(led_idle_start);
- tick_nohz_stop_sched_tick();
+ tick_nohz_stop_sched_tick(1);
while (!need_resched())
idle();
leds_event(led_idle_end);
{
/* endless idle loop with no priority at all */
while (1) {
- tick_nohz_stop_sched_tick();
+ tick_nohz_stop_sched_tick(1);
while (!need_resched()) {
#ifdef CONFIG_SMTC_IDLE_HOOK_DEBUG
extern void smtc_idle_loop_hook(void);
*childregs = *regs;
childregs->regs[7] = 0; /* Clear error flag */
- #if defined(CONFIG_BINFMT_IRIX)
- if (current->personality != PER_LINUX) {
- /* Under IRIX things are a little different. */
- childregs->regs[3] = 1;
- regs->regs[3] = 0;
- }
- #endif
childregs->regs[2] = 0; /* Child gets zero as return value */
regs->regs[2] = p->pid;
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
- static int hlt_counter;
-
- unsigned long boot_option_idle_override = 0;
- EXPORT_SYMBOL(boot_option_idle_override);
-
DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
EXPORT_PER_CPU_SYMBOL(current_task);
return ((unsigned long *)tsk->thread.sp)[3];
}
- /*
- * Powermanagement idle function, if any..
- */
- void (*pm_idle)(void);
- EXPORT_SYMBOL(pm_idle);
+ #ifdef CONFIG_HOTPLUG_CPU
+ #include <asm/nmi.h>
- void disable_hlt(void)
+ static void cpu_exit_clear(void)
{
- hlt_counter++;
- }
+ int cpu = raw_smp_processor_id();
- EXPORT_SYMBOL(disable_hlt);
+ idle_task_exit();
- void enable_hlt(void)
- {
- hlt_counter--;
- }
+ cpu_uninit();
+ irq_ctx_exit(cpu);
- EXPORT_SYMBOL(enable_hlt);
+ cpu_clear(cpu, cpu_callout_map);
+ cpu_clear(cpu, cpu_callin_map);
- /*
- * We use this if we don't have any better
- * idle routine..
- */
- void default_idle(void)
- {
- if (!hlt_counter && boot_cpu_data.hlt_works_ok) {
- current_thread_info()->status &= ~TS_POLLING;
- /*
- * TS_POLLING-cleared state must be visible before we
- * test NEED_RESCHED:
- */
- smp_mb();
-
- if (!need_resched())
- safe_halt(); /* enables interrupts racelessly */
- else
- local_irq_enable();
- current_thread_info()->status |= TS_POLLING;
- } else {
- local_irq_enable();
- /* loop is done by the caller */
- cpu_relax();
- }
+ numa_remove_cpu(cpu);
}
- #ifdef CONFIG_APM_MODULE
- EXPORT_SYMBOL(default_idle);
- #endif
- #ifdef CONFIG_HOTPLUG_CPU
- #include <asm/nmi.h>
/* We don't actually take CPU down, just spin without interrupts. */
static inline void play_dead(void)
{
/* endless idle loop with no priority at all */
while (1) {
- tick_nohz_stop_sched_tick();
+ tick_nohz_stop_sched_tick(1);
while (!need_resched()) {
- void (*idle)(void);
check_pgt_cache();
rmb();
- idle = pm_idle;
if (rcu_pending(cpu))
rcu_check_callbacks(cpu, 0);
- if (!idle)
- idle = default_idle;
-
if (cpu_is_offline(cpu))
play_dead();
local_irq_disable();
__get_cpu_var(irq_stat).idle_timestamp = jiffies;
- idle();
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
+ pm_idle();
+ start_critical_timings();
}
tick_nohz_restart_sched_tick();
preempt_enable_no_resched();
/*
* Forget coprocessor state..
*/
+ tsk->fpu_counter = 0;
clear_fpu(tsk);
clear_used_math();
}
/* If the task has used fpu the last 5 timeslices, just do a full
* restore of the math state immediately to avoid the trap; the
* chances of needing FPU soon are obviously high now
+ *
+ * tsk_used_math() checks prevent calling math_state_restore(),
+ * which can sleep in the case of !tsk_used_math()
*/
- if (next_p->fpu_counter > 5)
+ if (tsk_used_math(next_p) && next_p->fpu_counter > 5)
math_state_restore();
/*
unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED;
- unsigned long boot_option_idle_override = 0;
- EXPORT_SYMBOL(boot_option_idle_override);
-
- /*
- * Powermanagement idle function, if any..
- */
- void (*pm_idle)(void);
- EXPORT_SYMBOL(pm_idle);
-
static ATOMIC_NOTIFIER_HEAD(idle_notifier);
void idle_notifier_register(struct notifier_block *n)
__exit_idle();
}
- /*
- * We use this if we don't have any better
- * idle routine..
- */
- void default_idle(void)
- {
- current_thread_info()->status &= ~TS_POLLING;
- /*
- * TS_POLLING-cleared state must be visible before we
- * test NEED_RESCHED:
- */
- smp_mb();
- if (!need_resched())
- safe_halt(); /* enables interrupts racelessly */
- else
- local_irq_enable();
- current_thread_info()->status |= TS_POLLING;
- }
-
#ifdef CONFIG_HOTPLUG_CPU
DECLARE_PER_CPU(int, cpu_state);
current_thread_info()->status |= TS_POLLING;
/* endless idle loop with no priority at all */
while (1) {
- tick_nohz_stop_sched_tick();
+ tick_nohz_stop_sched_tick(1);
while (!need_resched()) {
- void (*idle)(void);
rmb();
- idle = pm_idle;
- if (!idle)
- idle = default_idle;
+
if (cpu_is_offline(smp_processor_id()))
play_dead();
/*
*/
local_irq_disable();
enter_idle();
- idle();
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
+ pm_idle();
+ start_critical_timings();
/* In many cases the interrupt that ended idle
has already called exit_idle. But some idle
loops can be woken up without interrupt. */
/*
* Forget coprocessor state..
*/
+ tsk->fpu_counter = 0;
clear_fpu(tsk);
clear_used_math();
}
p->thread.fs = me->thread.fs;
p->thread.gs = me->thread.gs;
- asm("mov %%gs,%0" : "=m" (p->thread.gsindex));
- asm("mov %%fs,%0" : "=m" (p->thread.fsindex));
- asm("mov %%es,%0" : "=m" (p->thread.es));
- asm("mov %%ds,%0" : "=m" (p->thread.ds));
+ savesegment(gs, p->thread.gsindex);
+ savesegment(fs, p->thread.fsindex);
+ savesegment(es, p->thread.es);
+ savesegment(ds, p->thread.ds);
if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) {
p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
void
start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
{
- asm volatile("movl %0, %%fs; movl %0, %%es; movl %0, %%ds" :: "r"(0));
+ loadsegment(fs, 0);
+ loadsegment(es, 0);
+ loadsegment(ds, 0);
load_gs_index(0);
regs->ip = new_ip;
regs->sp = new_sp;
*next = &next_p->thread;
int cpu = smp_processor_id();
struct tss_struct *tss = &per_cpu(init_tss, cpu);
+ unsigned fsindex, gsindex;
/* we're going to use this soon, after a few expensive things */
if (next_p->fpu_counter>5)
* Switch DS and ES.
* This won't pick up thread selector changes, but I guess that is ok.
*/
- asm volatile("mov %%es,%0" : "=m" (prev->es));
+ savesegment(es, prev->es);
if (unlikely(next->es | prev->es))
loadsegment(es, next->es);
-
- asm volatile ("mov %%ds,%0" : "=m" (prev->ds));
+
+ savesegment(ds, prev->ds);
if (unlikely(next->ds | prev->ds))
loadsegment(ds, next->ds);
+
+ /* We must save %fs and %gs before load_TLS() because
+ * %fs and %gs may be cleared by load_TLS().
+ *
+ * (e.g. xen_load_tls())
+ */
+ savesegment(fs, fsindex);
+ savesegment(gs, gsindex);
+
load_TLS(next, cpu);
+ /*
+ * Leave lazy mode, flushing any hypercalls made here.
+ * This must be done before restoring TLS segments so
+ * the GDT and LDT are properly updated, and must be
+ * done before math_state_restore, so the TS bit is up
+ * to date.
+ */
+ arch_leave_lazy_cpu_mode();
+
/*
* Switch FS and GS.
*/
{
- unsigned fsindex;
- asm volatile("movl %%fs,%0" : "=r" (fsindex));
/* segment register != 0 always requires a reload.
also reload when it has changed.
when prev process used 64bit base always reload
if (next->fs)
wrmsrl(MSR_FS_BASE, next->fs);
prev->fsindex = fsindex;
- }
- {
- unsigned gsindex;
- asm volatile("movl %%gs,%0" : "=r" (gsindex));
+
if (unlikely(gsindex | next->gsindex | prev->gs)) {
load_gs_index(next->gsindex);
if (gsindex)
/* If the task has used fpu the last 5 timeslices, just do a full
* restore of the math state immediately to avoid the trap; the
* chances of needing FPU soon are obviously high now
+ *
+ * tsk_used_math() checks prevent calling math_state_restore(),
+ * which can sleep in the case of !tsk_used_math()
*/
- if (next_p->fpu_counter>5)
+ if (tsk_used_math(next_p) && next_p->fpu_counter > 5)
math_state_restore();
return prev_p;
}
set_32bit_tls(task, FS_TLS, addr);
if (doit) {
load_TLS(&task->thread, cpu);
- asm volatile("movl %0,%%fs" :: "r"(FS_TLS_SEL));
+ loadsegment(fs, FS_TLS_SEL);
}
task->thread.fsindex = FS_TLS_SEL;
task->thread.fs = 0;
if (doit) {
/* set the selector to 0 to not confuse
__switch_to */
- asm volatile("movl %0,%%fs" :: "r" (0));
+ loadsegment(fs, 0);
ret = checking_wrmsrl(MSR_FS_BASE, addr);
}
}
if (task->thread.gsindex == GS_TLS_SEL)
base = read_32bit_tls(task, GS_TLS);
else if (doit) {
- asm("movl %%gs,%0" : "=r" (gsindex));
+ savesegment(gs, gsindex);
if (gsindex)
rdmsrl(MSR_KERNEL_GS_BASE, base);
else
EXPORT_SYMBOL(_local_bh_enable);
- void local_bh_enable(void)
+ static inline void _local_bh_enable_ip(unsigned long ip)
{
+ WARN_ON_ONCE(in_irq() || irqs_disabled());
#ifdef CONFIG_TRACE_IRQFLAGS
- unsigned long flags;
-
- WARN_ON_ONCE(in_irq());
- #endif
- WARN_ON_ONCE(irqs_disabled());
-
- #ifdef CONFIG_TRACE_IRQFLAGS
- local_irq_save(flags);
+ local_irq_disable();
#endif
/*
* Are softirqs going to be turned on now:
*/
if (softirq_count() == SOFTIRQ_OFFSET)
- trace_softirqs_on((unsigned long)__builtin_return_address(0));
+ trace_softirqs_on(ip);
/*
* Keep preemption disabled until we are done with
* softirq processing:
dec_preempt_count();
#ifdef CONFIG_TRACE_IRQFLAGS
- local_irq_restore(flags);
+ local_irq_enable();
#endif
preempt_check_resched();
}
+
+ void local_bh_enable(void)
+ {
+ _local_bh_enable_ip((unsigned long)__builtin_return_address(0));
+ }
EXPORT_SYMBOL(local_bh_enable);
void local_bh_enable_ip(unsigned long ip)
{
- #ifdef CONFIG_TRACE_IRQFLAGS
- unsigned long flags;
-
- WARN_ON_ONCE(in_irq());
-
- local_irq_save(flags);
- #endif
- /*
- * Are softirqs going to be turned on now:
- */
- if (softirq_count() == SOFTIRQ_OFFSET)
- trace_softirqs_on(ip);
- /*
- * Keep preemption disabled until we are done with
- * softirq processing:
- */
- sub_preempt_count(SOFTIRQ_OFFSET - 1);
-
- if (unlikely(!in_interrupt() && local_softirq_pending()))
- do_softirq();
-
- dec_preempt_count();
- #ifdef CONFIG_TRACE_IRQFLAGS
- local_irq_restore(flags);
- #endif
- preempt_check_resched();
+ _local_bh_enable_ip(ip);
}
EXPORT_SYMBOL(local_bh_enable_ip);
#ifdef CONFIG_NO_HZ
/* Make sure that timer wheel updates are propagated */
if (!in_interrupt() && idle_cpu(smp_processor_id()) && !need_resched())
- tick_nohz_stop_sched_tick();
+ tick_nohz_stop_sched_tick(0);
rcu_irq_exit();
#endif
preempt_enable_no_resched();
local_irq_restore(flags);
}
- void open_softirq(int nr, void (*action)(struct softirq_action*), void *data)
+ void open_softirq(int nr, void (*action)(struct softirq_action *))
{
- softirq_vec[nr].data = data;
softirq_vec[nr].action = action;
}
struct tasklet_struct **tail;
};
- /* Some compilers disobey section attribute on statics when not
- initialized -- RR */
- static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec) = { NULL };
- static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec) = { NULL };
+ static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec);
+ static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec);
void __tasklet_schedule(struct tasklet_struct *t)
{
&per_cpu(tasklet_hi_vec, cpu).head;
}
- open_softirq(TASKLET_SOFTIRQ, tasklet_action, NULL);
- open_softirq(HI_SOFTIRQ, tasklet_hi_action, NULL);
+ open_softirq(TASKLET_SOFTIRQ, tasklet_action);
+ open_softirq(HI_SOFTIRQ, tasklet_hi_action);
}
static int ksoftirqd(void * __bind_cpu)
p = per_cpu(ksoftirqd, hotcpu);
per_cpu(ksoftirqd, hotcpu) = NULL;
- sched_setscheduler(p, SCHED_FIFO, ¶m);
+ sched_setscheduler_nocheck(p, SCHED_FIFO, ¶m);
kthread_stop(p);
takeover_tasklets(hotcpu);
break;
/*
* Call a function on all processors
*/
- int on_each_cpu(void (*func) (void *info), void *info, int retry, int wait)
+ int on_each_cpu(void (*func) (void *info), void *info, int wait)
{
int ret = 0;
preempt_disable();
- ret = smp_call_function(func, info, retry, wait);
+ ret = smp_call_function(func, info, wait);
local_irq_disable();
func(info);
local_irq_enable();
* Called either from the idle loop or from irq_exit() when an idle period was
* just interrupted by an interrupt which did not cause a reschedule.
*/
-void tick_nohz_stop_sched_tick(void)
+void tick_nohz_stop_sched_tick(int inidle)
{
unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
struct tick_sched *ts;
if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
goto end;
+ if (!inidle && !ts->inidle)
+ goto end;
+
+ ts->inidle = 1;
+
if (need_resched())
goto end;
ts->tick_stopped = 1;
ts->idle_jiffies = last_jiffies;
rcu_enter_nohz();
+ sched_clock_tick_stop(cpu);
}
/*
local_irq_disable();
tick_nohz_stop_idle(cpu);
- if (!ts->tick_stopped) {
+ if (!ts->inidle || !ts->tick_stopped) {
+ ts->inidle = 0;
local_irq_enable();
return;
}
+ ts->inidle = 0;
+
rcu_exit_nohz();
/* Update jiffies first */
select_nohz_load_balancer(0);
now = ktime_get();
tick_do_update_jiffies64(now);
+ sched_clock_tick_start(cpu);
cpu_clear(cpu, nohz_cpu_mask);
/*