Merge branch 'audit.b37' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit...

[sfrench/cifs-2.6.git] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 8a0afb97af71c99f14a01f7974a88886fd7d8f08..0dc757246d89b02c96593df44ff8d75acb93e711 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -56,6 +56,16 @@
 
 #include <asm/unistd.h>
 
+/*
+ * Scheduler clock - returns current time in nanosec units.
+ * This is default implementation.
+ * Architectures and sub-architectures can override this.
+ */
+unsigned long long __attribute__((weak)) sched_clock(void)
+{
+       return (unsigned long long)jiffies * (1000000000 / HZ);
+}
+
 /*
  * Convert user-nice values [ -20 ... 0 ... 19 ]
  * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
@@ -1567,6 +1577,7 @@ int fastcall wake_up_state(struct task_struct *p, unsigned int state)
        return try_to_wake_up(p, state, 0);
 }
 
+static void task_running_tick(struct rq *rq, struct task_struct *p);
 /*
  * Perform scheduler related setup for a newly forked process p.
  * p is forked by current.
@@ -1627,7 +1638,7 @@ void fastcall sched_fork(struct task_struct *p, int clone_flags)
                 * runqueue lock is not a problem.
                 */
                current->time_slice = 1;
-               scheduler_tick();
+               task_running_tick(cpu_rq(cpu), current);
        }
        local_irq_enable();
        put_cpu();
@@ -1842,6 +1853,13 @@ context_switch(struct rq *rq, struct task_struct *prev,
        struct mm_struct *mm = next->mm;
        struct mm_struct *oldmm = prev->active_mm;
 
+       /*
+        * For paravirt, this is coupled with an exit in switch_to to
+        * combine the page table reload and the switch backend into
+        * one hypercall.
+        */
+       arch_enter_lazy_cpu_mode();
+
        if (!mm) {
                next->active_mm = oldmm;
                atomic_inc(&oldmm->mm_count);
@@ -2886,14 +2904,16 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu)
 static void update_load(struct rq *this_rq)
 {
        unsigned long this_load;
-       int i, scale;
+       unsigned int i, scale;
 
        this_load = this_rq->raw_weighted_load;
 
        /* Update our load: */
-       for (i = 0, scale = 1; i < 3; i++, scale <<= 1) {
+       for (i = 0, scale = 1; i < 3; i++, scale += scale) {
                unsigned long old_load, new_load;
 
+               /* scale is effectively 1 << i now, and >> i divides by scale */
+
                old_load = this_rq->cpu_load[i];
                new_load = this_load;
                /*
@@ -2903,7 +2923,7 @@ static void update_load(struct rq *this_rq)
                 */
                if (new_load > old_load)
                        new_load += scale-1;
-               this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) / scale;
+               this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i;
        }
 }
 
@@ -3429,6 +3449,8 @@ asmlinkage void __sched schedule(void)
                        "%s/0x%08x/%d\n",
                        current->comm, preempt_count(), current->pid);
                debug_show_held_locks(current);
+               if (irqs_disabled())
+                       print_irqtrace_events(current);
                dump_stack();
        }
        profile_hit(SCHED_PROFILING, __builtin_return_address(0));
@@ -4190,13 +4212,12 @@ static void __setscheduler(struct task_struct *p, int policy, int prio)
 }
 
 /**
- * sched_setscheduler - change the scheduling policy and/or RT priority of
- * a thread.
+ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
  * @p: the task in question.
  * @policy: new policy.
  * @param: structure containing the new RT priority.
  *
- * NOTE: the task may be already dead
+ * NOTE that the task may be already dead.
  */
 int sched_setscheduler(struct task_struct *p, int policy,
                       struct sched_param *param)
@@ -4564,7 +4585,7 @@ asmlinkage long sys_sched_getaffinity(pid_t pid, unsigned int len,
 /**
  * sys_sched_yield - yield the current processor to other threads.
  *
- * this function yields the current CPU by moving the calling thread
+ * This function yields the current CPU by moving the calling thread
  * to the expired array. If there are no other threads running on this
  * CPU then this function will return.
  */
@@ -4614,15 +4635,6 @@ asmlinkage long sys_sched_yield(void)
        return 0;
 }
 
-static inline int __resched_legal(int expected_preempt_count)
-{
-       if (unlikely(preempt_count() != expected_preempt_count))
-               return 0;
-       if (unlikely(system_state != SYSTEM_RUNNING))
-               return 0;
-       return 1;
-}
-
 static void __cond_resched(void)
 {
 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
@@ -4642,7 +4654,8 @@ static void __cond_resched(void)
 
 int __sched cond_resched(void)
 {
-       if (need_resched() && __resched_legal(0)) {
+       if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) &&
+                                       system_state == SYSTEM_RUNNING) {
                __cond_resched();
                return 1;
        }
@@ -4668,7 +4681,7 @@ int cond_resched_lock(spinlock_t *lock)
                ret = 1;
                spin_lock(lock);
        }
-       if (need_resched() && __resched_legal(1)) {
+       if (need_resched() && system_state == SYSTEM_RUNNING) {
                spin_release(&lock->dep_map, 1, _THIS_IP_);
                _raw_spin_unlock(lock);
                preempt_enable_no_resched();
@@ -4684,7 +4697,7 @@ int __sched cond_resched_softirq(void)
 {
        BUG_ON(!in_softirq());
 
-       if (need_resched() && __resched_legal(0)) {
+       if (need_resched() && system_state == SYSTEM_RUNNING) {
                raw_local_irq_disable();
                _local_bh_enable();
                raw_local_irq_enable();
@@ -4699,7 +4712,7 @@ EXPORT_SYMBOL(cond_resched_softirq);
 /**
  * yield - yield the current processor to other threads.
  *
- * this is a shortcut for kernel-space yielding - it marks the
+ * This is a shortcut for kernel-space yielding - it marks the
  * thread runnable and calls sys_sched_yield().
  */
 void __sched yield(void)
@@ -5605,7 +5618,7 @@ static void cpu_attach_domain(struct sched_domain *sd, int cpu)
 }
 
 /* cpus with isolated domains */
-static cpumask_t __cpuinitdata cpu_isolated_map = CPU_MASK_NONE;
+static cpumask_t cpu_isolated_map = CPU_MASK_NONE;
 
 /* Setup the mask of cpus configured for isolated domains */
 static int __init isolated_cpu_setup(char *str)
@@ -6870,7 +6883,7 @@ void __init sched_init_smp(void)
 
        lock_cpu_hotplug();
        arch_init_sched_domains(&cpu_online_map);
-       cpus_andnot(non_isolated_cpus, cpu_online_map, cpu_isolated_map);
+       cpus_andnot(non_isolated_cpus, cpu_possible_map, cpu_isolated_map);
        if (cpus_empty(non_isolated_cpus))
                cpu_set(smp_processor_id(), non_isolated_cpus);
        unlock_cpu_hotplug();
@@ -6977,6 +6990,8 @@ void __might_sleep(char *file, int line)
                printk("in_atomic():%d, irqs_disabled():%d\n",
                        in_atomic(), irqs_disabled());
                debug_show_held_locks(current);
+               if (irqs_disabled())
+                       print_irqtrace_events(current);
                dump_stack();
        }
 #endif