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-rw-r--r--kernel/sched.c360
1 files changed, 194 insertions, 166 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index f4778d1aef6..b0326141f84 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -184,9 +184,6 @@ static inline unsigned int task_timeslice(task_t *p)
return static_prio_timeslice(p->static_prio);
}
-#define task_hot(p, now, sd) ((long long) ((now) - (p)->last_ran) \
- < (long long) (sd)->cache_hot_time)
-
/*
* These are the runqueue data structures:
*/
@@ -278,8 +275,8 @@ static DEFINE_PER_CPU(struct runqueue, runqueues);
* The domain tree of any CPU may only be accessed from within
* preempt-disabled sections.
*/
-#define for_each_domain(cpu, domain) \
-for (domain = rcu_dereference(cpu_rq(cpu)->sd); domain; domain = domain->parent)
+#define for_each_domain(cpu, __sd) \
+ for (__sd = rcu_dereference(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent)
#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
#define this_rq() (&__get_cpu_var(runqueues))
@@ -1039,6 +1036,7 @@ static int migrate_task(task_t *p, int dest_cpu, migration_req_t *req)
req->task = p;
req->dest_cpu = dest_cpu;
list_add(&req->list, &rq->migration_queue);
+
return 1;
}
@@ -1135,7 +1133,7 @@ static inline unsigned long cpu_avg_load_per_task(int cpu)
runqueue_t *rq = cpu_rq(cpu);
unsigned long n = rq->nr_running;
- return n ? rq->raw_weighted_load / n : SCHED_LOAD_SCALE;
+ return n ? rq->raw_weighted_load / n : SCHED_LOAD_SCALE;
}
/*
@@ -1494,7 +1492,6 @@ int fastcall wake_up_process(task_t *p)
return try_to_wake_up(p, TASK_STOPPED | TASK_TRACED |
TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE, 0);
}
-
EXPORT_SYMBOL(wake_up_process);
int fastcall wake_up_state(task_t *p, unsigned int state)
@@ -1867,6 +1864,15 @@ unsigned long nr_active(void)
#ifdef CONFIG_SMP
/*
+ * Is this task likely cache-hot:
+ */
+static inline int
+task_hot(struct task_struct *p, unsigned long long now, struct sched_domain *sd)
+{
+ return (long long)(now - p->last_ran) < (long long)sd->cache_hot_time;
+}
+
+/*
* double_rq_lock - safely lock two runqueues
*
* Note this does not disable interrupts like task_rq_lock,
@@ -2029,6 +2035,7 @@ int can_migrate_task(task_t *p, runqueue_t *rq, int this_cpu,
}
#define rq_best_prio(rq) min((rq)->curr->prio, (rq)->best_expired_prio)
+
/*
* move_tasks tries to move up to max_nr_move tasks and max_load_move weighted
* load from busiest to this_rq, as part of a balancing operation within
@@ -2041,11 +2048,10 @@ static int move_tasks(runqueue_t *this_rq, int this_cpu, runqueue_t *busiest,
struct sched_domain *sd, enum idle_type idle,
int *all_pinned)
{
+ int idx, pulled = 0, pinned = 0, this_best_prio, best_prio,
+ best_prio_seen, skip_for_load;
prio_array_t *array, *dst_array;
struct list_head *head, *curr;
- int idx, pulled = 0, pinned = 0, this_best_prio, busiest_best_prio;
- int busiest_best_prio_seen;
- int skip_for_load; /* skip the task based on weighted load issues */
long rem_load_move;
task_t *tmp;
@@ -2055,15 +2061,15 @@ static int move_tasks(runqueue_t *this_rq, int this_cpu, runqueue_t *busiest,
rem_load_move = max_load_move;
pinned = 1;
this_best_prio = rq_best_prio(this_rq);
- busiest_best_prio = rq_best_prio(busiest);
+ best_prio = rq_best_prio(busiest);
/*
* Enable handling of the case where there is more than one task
* with the best priority. If the current running task is one
- * of those with prio==busiest_best_prio we know it won't be moved
+ * of those with prio==best_prio we know it won't be moved
* and therefore it's safe to override the skip (based on load) of
* any task we find with that prio.
*/
- busiest_best_prio_seen = busiest_best_prio == busiest->curr->prio;
+ best_prio_seen = best_prio == busiest->curr->prio;
/*
* We first consider expired tasks. Those will likely not be
@@ -2110,10 +2116,11 @@ skip_queue:
*/
skip_for_load = tmp->load_weight > rem_load_move;
if (skip_for_load && idx < this_best_prio)
- skip_for_load = !busiest_best_prio_seen && idx == busiest_best_prio;
+ skip_for_load = !best_prio_seen && idx == best_prio;
if (skip_for_load ||
!can_migrate_task(tmp, busiest, this_cpu, sd, idle, &pinned)) {
- busiest_best_prio_seen |= idx == busiest_best_prio;
+
+ best_prio_seen |= idx == best_prio;
if (curr != head)
goto skip_queue;
idx++;
@@ -2156,8 +2163,8 @@ out:
/*
* find_busiest_group finds and returns the busiest CPU group within the
- * domain. It calculates and returns the amount of weighted load which should be
- * moved to restore balance via the imbalance parameter.
+ * domain. It calculates and returns the amount of weighted load which
+ * should be moved to restore balance via the imbalance parameter.
*/
static struct sched_group *
find_busiest_group(struct sched_domain *sd, int this_cpu,
@@ -2279,7 +2286,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
* capacity but still has some space to pick up some load
* from other group and save more power
*/
- if (sum_nr_running <= group_capacity - 1)
+ if (sum_nr_running <= group_capacity - 1) {
if (sum_nr_running > leader_nr_running ||
(sum_nr_running == leader_nr_running &&
first_cpu(group->cpumask) >
@@ -2287,7 +2294,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
group_leader = group;
leader_nr_running = sum_nr_running;
}
-
+ }
group_next:
#endif
group = group->next;
@@ -2342,8 +2349,7 @@ group_next:
* moved
*/
if (*imbalance < busiest_load_per_task) {
- unsigned long pwr_now, pwr_move;
- unsigned long tmp;
+ unsigned long tmp, pwr_now, pwr_move;
unsigned int imbn;
small_imbalance:
@@ -2415,22 +2421,23 @@ ret:
/*
* find_busiest_queue - find the busiest runqueue among the cpus in group.
*/
-static runqueue_t *find_busiest_queue(struct sched_group *group,
- enum idle_type idle, unsigned long imbalance)
+static runqueue_t *
+find_busiest_queue(struct sched_group *group, enum idle_type idle,
+ unsigned long imbalance)
{
+ runqueue_t *busiest = NULL, *rq;
unsigned long max_load = 0;
- runqueue_t *busiest = NULL, *rqi;
int i;
for_each_cpu_mask(i, group->cpumask) {
- rqi = cpu_rq(i);
+ rq = cpu_rq(i);
- if (rqi->nr_running == 1 && rqi->raw_weighted_load > imbalance)
+ if (rq->nr_running == 1 && rq->raw_weighted_load > imbalance)
continue;
- if (rqi->raw_weighted_load > max_load) {
- max_load = rqi->raw_weighted_load;
- busiest = rqi;
+ if (rq->raw_weighted_load > max_load) {
+ max_load = rq->raw_weighted_load;
+ busiest = rq;
}
}
@@ -2443,7 +2450,11 @@ static runqueue_t *find_busiest_queue(struct sched_group *group,
*/
#define MAX_PINNED_INTERVAL 512
-#define minus_1_or_zero(n) ((n) > 0 ? (n) - 1 : 0)
+static inline unsigned long minus_1_or_zero(unsigned long n)
+{
+ return n > 0 ? n - 1 : 0;
+}
+
/*
* Check this_cpu to ensure it is balanced within domain. Attempt to move
* tasks if there is an imbalance.
@@ -2453,12 +2464,10 @@ static runqueue_t *find_busiest_queue(struct sched_group *group,
static int load_balance(int this_cpu, runqueue_t *this_rq,
struct sched_domain *sd, enum idle_type idle)
{
+ int nr_moved, all_pinned = 0, active_balance = 0, sd_idle = 0;
struct sched_group *group;
- runqueue_t *busiest;
unsigned long imbalance;
- int nr_moved, all_pinned = 0;
- int active_balance = 0;
- int sd_idle = 0;
+ runqueue_t *busiest;
if (idle != NOT_IDLE && sd->flags & SD_SHARE_CPUPOWER &&
!sched_smt_power_savings)
@@ -2492,8 +2501,8 @@ static int load_balance(int this_cpu, runqueue_t *this_rq,
*/
double_rq_lock(this_rq, busiest);
nr_moved = move_tasks(this_rq, this_cpu, busiest,
- minus_1_or_zero(busiest->nr_running),
- imbalance, sd, idle, &all_pinned);
+ minus_1_or_zero(busiest->nr_running),
+ imbalance, sd, idle, &all_pinned);
double_rq_unlock(this_rq, busiest);
/* All tasks on this runqueue were pinned by CPU affinity */
@@ -2566,7 +2575,8 @@ out_one_pinned:
(sd->balance_interval < sd->max_interval))
sd->balance_interval *= 2;
- if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && !sched_smt_power_savings)
+ if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
+ !sched_smt_power_savings)
return -1;
return 0;
}
@@ -2578,8 +2588,8 @@ out_one_pinned:
* Called from schedule when this_rq is about to become idle (NEWLY_IDLE).
* this_rq is locked.
*/
-static int load_balance_newidle(int this_cpu, runqueue_t *this_rq,
- struct sched_domain *sd)
+static int
+load_balance_newidle(int this_cpu, runqueue_t *this_rq, struct sched_domain *sd)
{
struct sched_group *group;
runqueue_t *busiest = NULL;
@@ -2628,9 +2638,11 @@ static int load_balance_newidle(int this_cpu, runqueue_t *this_rq,
out_balanced:
schedstat_inc(sd, lb_balanced[NEWLY_IDLE]);
- if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && !sched_smt_power_savings)
+ if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
+ !sched_smt_power_savings)
return -1;
sd->nr_balance_failed = 0;
+
return 0;
}
@@ -2644,10 +2656,9 @@ static void idle_balance(int this_cpu, runqueue_t *this_rq)
for_each_domain(this_cpu, sd) {
if (sd->flags & SD_BALANCE_NEWIDLE) {
- if (load_balance_newidle(this_cpu, this_rq, sd)) {
- /* We've pulled tasks over so stop searching */
+ /* If we've pulled tasks over stop searching: */
+ if (load_balance_newidle(this_cpu, this_rq, sd))
break;
- }
}
}
}
@@ -2666,8 +2677,8 @@ static void active_load_balance(runqueue_t *busiest_rq, int busiest_cpu)
runqueue_t *target_rq;
int target_cpu = busiest_rq->push_cpu;
+ /* Is there any task to move? */
if (busiest_rq->nr_running <= 1)
- /* no task to move */
return;
target_rq = cpu_rq(target_cpu);
@@ -2685,21 +2696,20 @@ static void active_load_balance(runqueue_t *busiest_rq, int busiest_cpu)
/* Search for an sd spanning us and the target CPU. */
for_each_domain(target_cpu, sd) {
if ((sd->flags & SD_LOAD_BALANCE) &&
- cpu_isset(busiest_cpu, sd->span))
+ cpu_isset(busiest_cpu, sd->span))
break;
}
- if (unlikely(sd == NULL))
- goto out;
-
- schedstat_inc(sd, alb_cnt);
+ if (likely(sd)) {
+ schedstat_inc(sd, alb_cnt);
- if (move_tasks(target_rq, target_cpu, busiest_rq, 1,
- RTPRIO_TO_LOAD_WEIGHT(100), sd, SCHED_IDLE, NULL))
- schedstat_inc(sd, alb_pushed);
- else
- schedstat_inc(sd, alb_failed);
-out:
+ if (move_tasks(target_rq, target_cpu, busiest_rq, 1,
+ RTPRIO_TO_LOAD_WEIGHT(100), sd, SCHED_IDLE,
+ NULL))
+ schedstat_inc(sd, alb_pushed);
+ else
+ schedstat_inc(sd, alb_failed);
+ }
spin_unlock(&target_rq->lock);
}
@@ -2712,23 +2722,27 @@ out:
* Balancing parameters are set up in arch_init_sched_domains.
*/
-/* Don't have all balancing operations going off at once */
-#define CPU_OFFSET(cpu) (HZ * cpu / NR_CPUS)
+/* Don't have all balancing operations going off at once: */
+static inline unsigned long cpu_offset(int cpu)
+{
+ return jiffies + cpu * HZ / NR_CPUS;
+}
-static void rebalance_tick(int this_cpu, runqueue_t *this_rq,
- enum idle_type idle)
+static void
+rebalance_tick(int this_cpu, runqueue_t *this_rq, enum idle_type idle)
{
- unsigned long old_load, this_load;
- unsigned long j = jiffies + CPU_OFFSET(this_cpu);
+ unsigned long this_load, interval, j = cpu_offset(this_cpu);
struct sched_domain *sd;
- int i;
+ int i, scale;
this_load = this_rq->raw_weighted_load;
- /* Update our load */
- for (i = 0; i < 3; i++) {
- unsigned long new_load = this_load;
- int scale = 1 << i;
+
+ /* Update our load: */
+ for (i = 0, scale = 1; i < 3; i++, scale <<= 1) {
+ unsigned long old_load, new_load;
+
old_load = this_rq->cpu_load[i];
+ new_load = this_load;
/*
* Round up the averaging division if load is increasing. This
* prevents us from getting stuck on 9 if the load is 10, for
@@ -2740,8 +2754,6 @@ static void rebalance_tick(int this_cpu, runqueue_t *this_rq,
}
for_each_domain(this_cpu, sd) {
- unsigned long interval;
-
if (!(sd->flags & SD_LOAD_BALANCE))
continue;
@@ -2782,6 +2794,7 @@ static inline void idle_balance(int cpu, runqueue_t *rq)
static inline int wake_priority_sleeper(runqueue_t *rq)
{
int ret = 0;
+
#ifdef CONFIG_SCHED_SMT
spin_lock(&rq->lock);
/*
@@ -2805,25 +2818,26 @@ EXPORT_PER_CPU_SYMBOL(kstat);
* This is called on clock ticks and on context switches.
* Bank in p->sched_time the ns elapsed since the last tick or switch.
*/
-static inline void update_cpu_clock(task_t *p, runqueue_t *rq,
- unsigned long long now)
+static inline void
+update_cpu_clock(task_t *p, runqueue_t *rq, unsigned long long now)
{
- unsigned long long last = max(p->timestamp, rq->timestamp_last_tick);
- p->sched_time += now - last;
+ p->sched_time += now - max(p->timestamp, rq->timestamp_last_tick);
}
/*
* Return current->sched_time plus any more ns on the sched_clock
* that have not yet been banked.
*/
-unsigned long long current_sched_time(const task_t *tsk)
+unsigned long long current_sched_time(const task_t *p)
{
unsigned long long ns;
unsigned long flags;
+
local_irq_save(flags);
- ns = max(tsk->timestamp, task_rq(tsk)->timestamp_last_tick);
- ns = tsk->sched_time + (sched_clock() - ns);
+ ns = max(p->timestamp, task_rq(p)->timestamp_last_tick);
+ ns = p->sched_time + sched_clock() - ns;
local_irq_restore(flags);
+
return ns;
}
@@ -2837,11 +2851,16 @@ unsigned long long current_sched_time(const task_t *tsk)
* increasing number of running tasks. We also ignore the interactivity
* if a better static_prio task has expired:
*/
-#define EXPIRED_STARVING(rq) \
- ((STARVATION_LIMIT && ((rq)->expired_timestamp && \
- (jiffies - (rq)->expired_timestamp >= \
- STARVATION_LIMIT * ((rq)->nr_running) + 1))) || \
- ((rq)->curr->static_prio > (rq)->best_expired_prio))
+static inline int expired_starving(runqueue_t *rq)
+{
+ if (rq->curr->static_prio > rq->best_expired_prio)
+ return 1;
+ if (!STARVATION_LIMIT || !rq->expired_timestamp)
+ return 0;
+ if (jiffies - rq->expired_timestamp > STARVATION_LIMIT * rq->nr_running)
+ return 1;
+ return 0;
+}
/*
* Account user cpu time to a process.
@@ -2925,10 +2944,10 @@ void account_steal_time(struct task_struct *p, cputime_t steal)
*/
void scheduler_tick(void)
{
+ unsigned long long now = sched_clock();
int cpu = smp_processor_id();
runqueue_t *rq = this_rq();
task_t *p = current;
- unsigned long long now = sched_clock();
update_cpu_clock(p, rq, now);
@@ -2978,7 +2997,7 @@ void scheduler_tick(void)
if (!rq->expired_timestamp)
rq->expired_timestamp = jiffies;
- if (!TASK_INTERACTIVE(p) || EXPIRED_STARVING(rq)) {
+ if (!TASK_INTERACTIVE(p) || expired_starving(rq)) {
enqueue_task(p, rq->expired);
if (p->static_prio < rq->best_expired_prio)
rq->best_expired_prio = p->static_prio;
@@ -3137,9 +3156,8 @@ unlock:
static inline void wake_sleeping_dependent(int this_cpu)
{
}
-
-static inline int dependent_sleeper(int this_cpu, runqueue_t *this_rq,
- task_t *p)
+static inline int
+dependent_sleeper(int this_cpu, runqueue_t *this_rq, task_t *p)
{
return 0;
}
@@ -3193,14 +3211,14 @@ static inline int interactive_sleep(enum sleep_type sleep_type)
*/
asmlinkage void __sched schedule(void)
{
- long *switch_count;
- task_t *prev, *next;
- runqueue_t *rq;
- prio_array_t *array;
struct list_head *queue;
unsigned long long now;
unsigned long run_time;
int cpu, idx, new_prio;
+ task_t *prev, *next;
+ prio_array_t *array;
+ long *switch_count;
+ runqueue_t *rq;
/*
* Test if we are atomic. Since do_exit() needs to call into
@@ -3353,7 +3371,6 @@ switch_tasks:
if (unlikely(test_thread_flag(TIF_NEED_RESCHED)))
goto need_resched;
}
-
EXPORT_SYMBOL(schedule);
#ifdef CONFIG_PREEMPT
@@ -3398,7 +3415,6 @@ need_resched:
if (unlikely(test_thread_flag(TIF_NEED_RESCHED)))
goto need_resched;
}
-
EXPORT_SYMBOL(preempt_schedule);
/*
@@ -3447,10 +3463,8 @@ need_resched:
int default_wake_function(wait_queue_t *curr, unsigned mode, int sync,
void *key)
{
- task_t *p = curr->private;
- return try_to_wake_up(p, mode, sync);
+ return try_to_wake_up(curr->private, mode, sync);
}
-
EXPORT_SYMBOL(default_wake_function);
/*
@@ -3468,13 +3482,11 @@ static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
struct list_head *tmp, *next;
list_for_each_safe(tmp, next, &q->task_list) {
- wait_queue_t *curr;
- unsigned flags;
- curr = list_entry(tmp, wait_queue_t, task_list);
- flags = curr->flags;
+ wait_queue_t *curr = list_entry(tmp, wait_queue_t, task_list);
+ unsigned flags = curr->flags;
+
if (curr->func(curr, mode, sync, key) &&
- (flags & WQ_FLAG_EXCLUSIVE) &&
- !--nr_exclusive)
+ (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
break;
}
}
@@ -3495,7 +3507,6 @@ void fastcall __wake_up(wait_queue_head_t *q, unsigned int mode,
__wake_up_common(q, mode, nr_exclusive, 0, key);
spin_unlock_irqrestore(&q->lock, flags);
}
-
EXPORT_SYMBOL(__wake_up);
/*
@@ -3564,6 +3575,7 @@ EXPORT_SYMBOL(complete_all);
void fastcall __sched wait_for_completion(struct completion *x)
{
might_sleep();
+
spin_lock_irq(&x->wait.lock);
if (!x->done) {
DECLARE_WAITQUEUE(wait, current);
@@ -3708,7 +3720,6 @@ void fastcall __sched interruptible_sleep_on(wait_queue_head_t *q)
schedule();
SLEEP_ON_TAIL
}
-
EXPORT_SYMBOL(interruptible_sleep_on);
long fastcall __sched
@@ -3724,7 +3735,6 @@ interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout)
return timeout;
}
-
EXPORT_SYMBOL(interruptible_sleep_on_timeout);
void fastcall __sched sleep_on(wait_queue_head_t *q)
@@ -3737,7 +3747,6 @@ void fastcall __sched sleep_on(wait_queue_head_t *q)
schedule();
SLEEP_ON_TAIL
}
-
EXPORT_SYMBOL(sleep_on);
long fastcall __sched sleep_on_timeout(wait_queue_head_t *q, long timeout)
@@ -3810,10 +3819,10 @@ void rt_mutex_setprio(task_t *p, int prio)
void set_user_nice(task_t *p, long nice)
{
+ int old_prio, delta;
unsigned long flags;
prio_array_t *array;
runqueue_t *rq;
- int old_prio, delta;
if (TASK_NICE(p) == nice || nice < -20 || nice > 19)
return;
@@ -3868,6 +3877,7 @@ int can_nice(const task_t *p, const int nice)
{
/* convert nice value [19,-20] to rlimit style value [1,40] */
int nice_rlim = 20 - nice;
+
return (nice_rlim <= p->signal->rlim[RLIMIT_NICE].rlim_cur ||
capable(CAP_SYS_NICE));
}
@@ -3883,8 +3893,7 @@ int can_nice(const task_t *p, const int nice)
*/
asmlinkage long sys_nice(int increment)
{
- int retval;
- long nice;
+ long nice, retval;
/*
* Setpriority might change our priority at the same moment.
@@ -3969,6 +3978,7 @@ static inline task_t *find_process_by_pid(pid_t pid)
static void __setscheduler(struct task_struct *p, int policy, int prio)
{
BUG_ON(p->array);
+
p->policy = policy;
p->rt_priority = prio;
p->normal_prio = normal_prio(p);
@@ -3992,8 +4002,7 @@ static void __setscheduler(struct task_struct *p, int policy, int prio)
int sched_setscheduler(struct task_struct *p, int policy,
struct sched_param *param)
{
- int retval;
- int oldprio, oldpolicy = -1;
+ int retval, oldprio, oldpolicy = -1;
prio_array_t *array;
unsigned long flags;
runqueue_t *rq;
@@ -4495,7 +4504,6 @@ void __sched yield(void)
set_current_state(TASK_RUNNING);
sys_sched_yield();
}
-
EXPORT_SYMBOL(yield);
/*
@@ -4513,7 +4521,6 @@ void __sched io_schedule(void)
schedule();
atomic_dec(&rq->nr_iowait);
}
-
EXPORT_SYMBOL(io_schedule);
long __sched io_schedule_timeout(long timeout)
@@ -4615,19 +4622,22 @@ out_unlock:
static inline struct task_struct *eldest_child(struct task_struct *p)
{
- if (list_empty(&p->children)) return NULL;
+ if (list_empty(&p->children))
+ return NULL;
return list_entry(p->children.next,struct task_struct,sibling);
}
static inline struct task_struct *older_sibling(struct task_struct *p)
{
- if (p->sibling.prev==&p->parent->children) return NULL;
+ if (p->sibling.prev==&p->parent->children)
+ return NULL;
return list_entry(p->sibling.prev,struct task_struct,sibling);
}
static inline struct task_struct *younger_sibling(struct task_struct *p)
{
- if (p->sibling.next==&p->parent->children) return NULL;
+ if (p->sibling.next==&p->parent->children)
+ return NULL;
return list_entry(p->sibling.next,struct task_struct,sibling);
}
@@ -4786,9 +4796,9 @@ cpumask_t nohz_cpu_mask = CPU_MASK_NONE;
int set_cpus_allowed(task_t *p, cpumask_t new_mask)
{
unsigned long flags;
- int ret = 0;
migration_req_t req;
runqueue_t *rq;
+ int ret = 0;
rq = task_rq_lock(p, &flags);
if (!cpus_intersects(new_mask, cpu_online_map)) {
@@ -4811,9 +4821,9 @@ int set_cpus_allowed(task_t *p, cpumask_t new_mask)
}
out:
task_rq_unlock(rq, &flags);
+
return ret;
}
-
EXPORT_SYMBOL_GPL(set_cpus_allowed);
/*
@@ -4874,8 +4884,8 @@ out:
*/
static int migration_thread(void *data)
{
- runqueue_t *rq;
int cpu = (long)data;
+ runqueue_t *rq;
rq = cpu_rq(cpu);
BUG_ON(rq->migration_thread != current);
@@ -4932,7 +4942,7 @@ wait_to_die:
#ifdef CONFIG_HOTPLUG_CPU
/* Figure out where task on dead CPU should go, use force if neccessary. */
-static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *tsk)
+static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
{
runqueue_t *rq;
unsigned long flags;
@@ -4942,18 +4952,18 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *tsk)
restart:
/* On same node? */
mask = node_to_cpumask(cpu_to_node(dead_cpu));
- cpus_and(mask, mask, tsk->cpus_allowed);
+ cpus_and(mask, mask, p->cpus_allowed);
dest_cpu = any_online_cpu(mask);
/* On any allowed CPU? */
if (dest_cpu == NR_CPUS)
- dest_cpu = any_online_cpu(tsk->cpus_allowed);
+ dest_cpu = any_online_cpu(p->cpus_allowed);
/* No more Mr. Nice Guy. */
if (dest_cpu == NR_CPUS) {
- rq = task_rq_lock(tsk, &flags);
- cpus_setall(tsk->cpus_allowed);
- dest_cpu = any_online_cpu(tsk->cpus_allowed);
+ rq = task_rq_lock(p, &flags);
+ cpus_setall(p->cpus_allowed);
+ dest_cpu = any_online_cpu(p->cpus_allowed);
task_rq_unlock(rq, &flags);
/*
@@ -4961,12 +4971,12 @@ restart:
* kernel threads (both mm NULL), since they never
* leave kernel.
*/
- if (tsk->mm && printk_ratelimit())
+ if (p->mm && printk_ratelimit())
printk(KERN_INFO "process %d (%s) no "
"longer affine to cpu%d\n",
- tsk->pid, tsk->comm, dead_cpu);
+ p->pid, p->comm, dead_cpu);
}
- if (!__migrate_task(tsk, dead_cpu, dest_cpu))
+ if (!__migrate_task(p, dead_cpu, dest_cpu))
goto restart;
}
@@ -4993,48 +5003,51 @@ static void migrate_nr_uninterruptible(runqueue_t *rq_src)
/* Run through task list and migrate tasks from the dead cpu. */
static void migrate_live_tasks(int src_cpu)
{
- struct task_struct *tsk, *t;
+ struct task_struct *p, *t;
write_lock_irq(&tasklist_lock);
- do_each_thread(t, tsk) {
- if (tsk == current)
+ do_each_thread(t, p) {
+ if (p == current)
continue;
- if (task_cpu(tsk) == src_cpu)
- move_task_off_dead_cpu(src_cpu, tsk);
- } while_each_thread(t, tsk);
+ if (task_cpu(p) == src_cpu)
+ move_task_off_dead_cpu(src_cpu, p);
+ } while_each_thread(t, p);
write_unlock_irq(&tasklist_lock);
}
/* Schedules idle task to be the next runnable task on current CPU.
* It does so by boosting its priority to highest possible and adding it to
- * the _front_ of runqueue. Used by CPU offline code.
+ * the _front_ of the runqueue. Used by CPU offline code.
*/
void sched_idle_next(void)
{
- int cpu = smp_processor_id();
- runqueue_t *rq = this_rq();
+ int this_cpu = smp_processor_id();
+ runqueue_t *rq = cpu_rq(this_cpu);
struct task_struct *p = rq->idle;
unsigned long flags;
/* cpu has to be offline */
- BUG_ON(cpu_online(cpu));
+ BUG_ON(cpu_online(this_cpu));
- /* Strictly not necessary since rest of the CPUs are stopped by now
- * and interrupts disabled on current cpu.
+ /*
+ * Strictly not necessary since rest of the CPUs are stopped by now
+ * and interrupts disabled on the current cpu.
*/
spin_lock_irqsave(&rq->lock, flags);
__setscheduler(p, SCHED_FIFO, MAX_RT_PRIO-1);
- /* Add idle task to _front_ of it's priority queue */
+
+ /* Add idle task to the _front_ of its priority queue: */
__activate_idle_task(p, rq);
spin_unlock_irqrestore(&rq->lock, flags);
}
-/* Ensures that the idle task is using init_mm right before its cpu goes
+/*
+ * Ensures that the idle task is using init_mm right before its cpu goes
* offline.
*/
void idle_task_exit(void)
@@ -5048,17 +5061,17 @@ void idle_task_exit(void)
mmdrop(mm);
}
-static void migrate_dead(unsigned int dead_cpu, task_t *tsk)
+static void migrate_dead(unsigned int dead_cpu, task_t *p)
{
struct runqueue *rq = cpu_rq(dead_cpu);
/* Must be exiting, otherwise would be on tasklist. */
- BUG_ON(tsk->exit_state != EXIT_ZOMBIE && tsk->exit_state != EXIT_DEAD);
+ BUG_ON(p->exit_state != EXIT_ZOMBIE && p->exit_state != EXIT_DEAD);
/* Cannot have done final schedule yet: would have vanished. */
- BUG_ON(tsk->flags & PF_DEAD);
+ BUG_ON(p->flags & PF_DEAD);
- get_task_struct(tsk);
+ get_task_struct(p);
/*
* Drop lock around migration; if someone else moves it,
@@ -5066,21 +5079,22 @@ static void migrate_dead(unsigned int dead_cpu, task_t *tsk)
* fine.
*/
spin_unlock_irq(&rq->lock);
- move_task_off_dead_cpu(dead_cpu, tsk);
+ move_task_off_dead_cpu(dead_cpu, p);
spin_lock_irq(&rq->lock);
- put_task_struct(tsk);
+ put_task_struct(p);
}
/* release_task() removes task from tasklist, so we won't find dead tasks. */
static void migrate_dead_tasks(unsigned int dead_cpu)
{
- unsigned arr, i;
struct runqueue *rq = cpu_rq(dead_cpu);
+ unsigned int arr, i;
for (arr = 0; arr < 2; arr++) {
for (i = 0; i < MAX_PRIO; i++) {
struct list_head *list = &rq->arrays[arr].queue[i];
+
while (!list_empty(list))
migrate_dead(dead_cpu,
list_entry(list->next, task_t,
@@ -5094,12 +5108,11 @@ static void migrate_dead_tasks(unsigned int dead_cpu)
* migration_call - callback that gets triggered when a CPU is added.
* Here we can start up the necessary migration thread for the new CPU.
*/
-static int __cpuinit migration_call(struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
+static int __cpuinit
+migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
- int cpu = (long)hcpu;
struct task_struct *p;
+ int cpu = (long)hcpu;
struct runqueue *rq;
unsigned long flags;
@@ -5116,10 +5129,12 @@ static int __cpuinit migration_call(struct notifier_block *nfb,
task_rq_unlock(rq, &flags);
cpu_rq(cpu)->migration_thread = p;
break;
+
case CPU_ONLINE:
/* Strictly unneccessary, as first user will wake it. */
wake_up_process(cpu_rq(cpu)->migration_thread);
break;
+
#ifdef CONFIG_HOTPLUG_CPU
case CPU_UP_CANCELED:
if (!cpu_rq(cpu)->migration_thread)
@@ -5130,6 +5145,7 @@ static int __cpuinit migration_call(struct notifier_block *nfb,
kthread_stop(cpu_rq(cpu)->migration_thread);
cpu_rq(cpu)->migration_thread = NULL;
break;
+
case CPU_DEAD:
migrate_live_tasks(cpu);
rq = cpu_rq(cpu);
@@ -5174,10 +5190,12 @@ static struct notifier_block __cpuinitdata migration_notifier = {
int __init migration_init(void)
{
void *cpu = (void *)(long)smp_processor_id();
- /* Start one for boot CPU. */
+
+ /* Start one for the boot CPU: */
migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
migration_call(&migration_notifier, CPU_ONLINE, cpu);
register_cpu_notifier(&migration_notifier);
+
return 0;
}
#endif
@@ -5273,7 +5291,7 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
} while (sd);
}
#else
-#define sched_domain_debug(sd, cpu) {}
+# define sched_domain_debug(sd, cpu) do { } while (0)
#endif
static int sd_degenerate(struct sched_domain *sd)
@@ -5299,8 +5317,8 @@ static int sd_degenerate(struct sched_domain *sd)
return 1;
}
-static int sd_parent_degenerate(struct sched_domain *sd,
- struct sched_domain *parent)
+static int
+sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
{
unsigned long cflags = sd->flags, pflags = parent->flags;
@@ -5595,8 +5613,8 @@ static void touch_cache(void *__cache, unsigned long __size)
/*
* Measure the cache-cost of one task migration. Returns in units of nsec.
*/
-static unsigned long long measure_one(void *cache, unsigned long size,
- int source, int target)
+static unsigned long long
+measure_one(void *cache, unsigned long size, int source, int target)
{
cpumask_t mask, saved_mask;
unsigned long long t0, t1, t2, t3, cost;
@@ -5946,9 +5964,9 @@ static int find_next_best_node(int node, unsigned long *used_nodes)
*/
static cpumask_t sched_domain_node_span(int node)
{
- int i;
- cpumask_t span, nodemask;
DECLARE_BITMAP(used_nodes, MAX_NUMNODES);
+ cpumask_t span, nodemask;
+ int i;
cpus_clear(span);
bitmap_zero(used_nodes, MAX_NUMNODES);
@@ -5959,6 +5977,7 @@ static cpumask_t sched_domain_node_span(int node)
for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
int next_node = find_next_best_node(node, used_nodes);
+
nodemask = node_to_cpumask(next_node);
cpus_or(span, span, nodemask);
}
@@ -5968,19 +5987,23 @@ static cpumask_t sched_domain_node_span(int node)
#endif
int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
+
/*
- * At the moment, CONFIG_SCHED_SMT is never defined, but leave it in so we
- * can switch it on easily if needed.
+ * SMT sched-domains:
*/
#ifdef CONFIG_SCHED_SMT
static DEFINE_PER_CPU(struct sched_domain, cpu_domains);
static struct sched_group sched_group_cpus[NR_CPUS];
+
static int cpu_to_cpu_group(int cpu)
{
return cpu;
}
#endif
+/*
+ * multi-core sched-domains:
+ */
#ifdef CONFIG_SCHED_MC
static DEFINE_PER_CPU(struct sched_domain, core_domains);
static struct sched_group *sched_group_core_bycpu[NR_CPUS];
@@ -6000,9 +6023,10 @@ static int cpu_to_core_group(int cpu)
static DEFINE_PER_CPU(struct sched_domain, phys_domains);
static struct sched_group *sched_group_phys_bycpu[NR_CPUS];
+
static int cpu_to_phys_group(int cpu)
{
-#if defined(CONFIG_SCHED_MC)
+#ifdef CONFIG_SCHED_MC
cpumask_t mask = cpu_coregroup_map(cpu);
return first_cpu(mask);
#elif defined(CONFIG_SCHED_SMT)
@@ -6548,6 +6572,7 @@ static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
{
int err = 0;
+
#ifdef CONFIG_SCHED_SMT
if (smt_capable())
err = sysfs_create_file(&cls->kset.kobj,
@@ -6567,7 +6592,8 @@ static ssize_t sched_mc_power_savings_show(struct sys_device *dev, char *page)
{
return sprintf(page, "%u\n", sched_mc_power_savings);
}
-static ssize_t sched_mc_power_savings_store(struct sys_device *dev, const char *buf, size_t count)
+static ssize_t sched_mc_power_savings_store(struct sys_device *dev,
+ const char *buf, size_t count)
{
return sched_power_savings_store(buf, count, 0);
}
@@ -6580,7 +6606,8 @@ static ssize_t sched_smt_power_savings_show(struct sys_device *dev, char *page)
{
return sprintf(page, "%u\n", sched_smt_power_savings);
}
-static ssize_t sched_smt_power_savings_store(struct sys_device *dev, const char *buf, size_t count)
+static ssize_t sched_smt_power_savings_store(struct sys_device *dev,
+ const char *buf, size_t count)
{
return sched_power_savings_store(buf, count, 1);
}
@@ -6642,6 +6669,7 @@ int in_sched_functions(unsigned long addr)
{
/* Linker adds these: start and end of __sched functions */
extern char __sched_text_start[], __sched_text_end[];
+
return in_lock_functions(addr) ||
(addr >= (unsigned long)__sched_text_start
&& addr < (unsigned long)__sched_text_end);
@@ -6649,11 +6677,11 @@ int in_sched_functions(unsigned long addr)
void __init sched_init(void)
{
- runqueue_t *rq;
int i, j, k;
for_each_possible_cpu(i) {
prio_array_t *array;
+ runqueue_t *rq;
rq = cpu_rq(i);
spin_lock_init(&rq->lock);
@@ -6704,7 +6732,7 @@ void __init sched_init(void)
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
void __might_sleep(char *file, int line)
{
-#if defined(in_atomic)
+#ifdef in_atomic
static unsigned long prev_jiffy; /* ratelimiting */
if ((in_atomic() || irqs_disabled()) &&
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 04:52:23 +0000