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authorIngo Molnar <mingo@elte.hu>2011-07-21 19:59:54 +0400
committerIngo Molnar <mingo@elte.hu>2011-07-21 20:00:01 +0400
commit994bf1c92270e3d7731ea08f1d1bd7a668314e60 (patch)
tree4409a21eab486e53fbe350a66e8a4f28b7a720c0 /kernel
parentbd96efe17d945f0bad56d592f8686dc6309905e7 (diff)
parentcf6ace16a3cd8b728fb0afa68368fd40bbeae19f (diff)
downloadlinux-994bf1c92270e3d7731ea08f1d1bd7a668314e60.tar.xz
Merge branch 'linus' into sched/core
Merge reason: pick up the latest scheduler fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/irq/generic-chip.c18
-rw-r--r--kernel/jump_label.c14
-rw-r--r--kernel/power/snapshot.c6
-rw-r--r--kernel/rcutree.c26
-rw-r--r--kernel/rcutree_plugin.h68
-rw-r--r--kernel/resource.c116
-rw-r--r--kernel/sched.c245
-rw-r--r--kernel/sched_fair.c46
-rw-r--r--kernel/sched_features.h2
-rw-r--r--kernel/signal.c19
-rw-r--r--kernel/softirq.c12
11 files changed, 450 insertions, 122 deletions
diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index 31a9db711906..3a2cab407b93 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -101,10 +101,10 @@ void irq_gc_unmask_enable_reg(struct irq_data *d)
}
/**
- * irq_gc_ack - Ack pending interrupt
+ * irq_gc_ack_set_bit - Ack pending interrupt via setting bit
* @d: irq_data
*/
-void irq_gc_ack(struct irq_data *d)
+void irq_gc_ack_set_bit(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
u32 mask = 1 << (d->irq - gc->irq_base);
@@ -115,6 +115,20 @@ void irq_gc_ack(struct irq_data *d)
}
/**
+ * irq_gc_ack_clr_bit - Ack pending interrupt via clearing bit
+ * @d: irq_data
+ */
+void irq_gc_ack_clr_bit(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ u32 mask = ~(1 << (d->irq - gc->irq_base));
+
+ irq_gc_lock(gc);
+ irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack);
+ irq_gc_unlock(gc);
+}
+
+/**
* irq_gc_mask_disable_reg_and_ack- Mask and ack pending interrupt
* @d: irq_data
*/
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index fa27e750dbc0..a8ce45097f3d 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -375,15 +375,19 @@ int jump_label_text_reserved(void *start, void *end)
static void jump_label_update(struct jump_label_key *key, int enable)
{
- struct jump_entry *entry = key->entries;
-
- /* if there are no users, entry can be NULL */
- if (entry)
- __jump_label_update(key, entry, __stop___jump_table, enable);
+ struct jump_entry *entry = key->entries, *stop = __stop___jump_table;
#ifdef CONFIG_MODULES
+ struct module *mod = __module_address((jump_label_t)key);
+
__jump_label_mod_update(key, enable);
+
+ if (mod)
+ stop = mod->jump_entries + mod->num_jump_entries;
#endif
+ /* if there are no users, entry can be NULL */
+ if (entry)
+ __jump_label_update(key, entry, stop, enable);
}
#endif
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index ace55889f702..06efa54f93d6 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1211,7 +1211,11 @@ static void free_unnecessary_pages(void)
to_free_highmem = alloc_highmem - save;
} else {
to_free_highmem = 0;
- to_free_normal -= save - alloc_highmem;
+ save -= alloc_highmem;
+ if (to_free_normal > save)
+ to_free_normal -= save;
+ else
+ to_free_normal = 0;
}
memory_bm_position_reset(&copy_bm);
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 7e59ffb3d0ba..ba06207b1dd3 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -84,9 +84,32 @@ DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
static struct rcu_state *rcu_state;
+/*
+ * The rcu_scheduler_active variable transitions from zero to one just
+ * before the first task is spawned. So when this variable is zero, RCU
+ * can assume that there is but one task, allowing RCU to (for example)
+ * optimized synchronize_sched() to a simple barrier(). When this variable
+ * is one, RCU must actually do all the hard work required to detect real
+ * grace periods. This variable is also used to suppress boot-time false
+ * positives from lockdep-RCU error checking.
+ */
int rcu_scheduler_active __read_mostly;
EXPORT_SYMBOL_GPL(rcu_scheduler_active);
+/*
+ * The rcu_scheduler_fully_active variable transitions from zero to one
+ * during the early_initcall() processing, which is after the scheduler
+ * is capable of creating new tasks. So RCU processing (for example,
+ * creating tasks for RCU priority boosting) must be delayed until after
+ * rcu_scheduler_fully_active transitions from zero to one. We also
+ * currently delay invocation of any RCU callbacks until after this point.
+ *
+ * It might later prove better for people registering RCU callbacks during
+ * early boot to take responsibility for these callbacks, but one step at
+ * a time.
+ */
+static int rcu_scheduler_fully_active __read_mostly;
+
#ifdef CONFIG_RCU_BOOST
/*
@@ -98,7 +121,6 @@ DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
DEFINE_PER_CPU(char, rcu_cpu_has_work);
-static char rcu_kthreads_spawnable;
#endif /* #ifdef CONFIG_RCU_BOOST */
@@ -1467,6 +1489,8 @@ static void rcu_process_callbacks(struct softirq_action *unused)
*/
static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
{
+ if (unlikely(!ACCESS_ONCE(rcu_scheduler_fully_active)))
+ return;
if (likely(!rsp->boost)) {
rcu_do_batch(rsp, rdp);
return;
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 14dc7dd00902..8aafbb80b8b0 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -68,6 +68,7 @@ struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt_state);
DEFINE_PER_CPU(struct rcu_data, rcu_preempt_data);
static struct rcu_state *rcu_state = &rcu_preempt_state;
+static void rcu_read_unlock_special(struct task_struct *t);
static int rcu_preempted_readers_exp(struct rcu_node *rnp);
/*
@@ -147,7 +148,7 @@ static void rcu_preempt_note_context_switch(int cpu)
struct rcu_data *rdp;
struct rcu_node *rnp;
- if (t->rcu_read_lock_nesting &&
+ if (t->rcu_read_lock_nesting > 0 &&
(t->rcu_read_unlock_special & RCU_READ_UNLOCK_BLOCKED) == 0) {
/* Possibly blocking in an RCU read-side critical section. */
@@ -190,6 +191,14 @@ static void rcu_preempt_note_context_switch(int cpu)
rnp->gp_tasks = &t->rcu_node_entry;
}
raw_spin_unlock_irqrestore(&rnp->lock, flags);
+ } else if (t->rcu_read_lock_nesting < 0 &&
+ t->rcu_read_unlock_special) {
+
+ /*
+ * Complete exit from RCU read-side critical section on
+ * behalf of preempted instance of __rcu_read_unlock().
+ */
+ rcu_read_unlock_special(t);
}
/*
@@ -284,7 +293,7 @@ static struct list_head *rcu_next_node_entry(struct task_struct *t,
* notify RCU core processing or task having blocked during the RCU
* read-side critical section.
*/
-static void rcu_read_unlock_special(struct task_struct *t)
+static noinline void rcu_read_unlock_special(struct task_struct *t)
{
int empty;
int empty_exp;
@@ -309,7 +318,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
}
/* Hardware IRQ handlers cannot block. */
- if (in_irq()) {
+ if (in_irq() || in_serving_softirq()) {
local_irq_restore(flags);
return;
}
@@ -342,6 +351,11 @@ static void rcu_read_unlock_special(struct task_struct *t)
#ifdef CONFIG_RCU_BOOST
if (&t->rcu_node_entry == rnp->boost_tasks)
rnp->boost_tasks = np;
+ /* Snapshot and clear ->rcu_boosted with rcu_node lock held. */
+ if (t->rcu_boosted) {
+ special |= RCU_READ_UNLOCK_BOOSTED;
+ t->rcu_boosted = 0;
+ }
#endif /* #ifdef CONFIG_RCU_BOOST */
t->rcu_blocked_node = NULL;
@@ -358,7 +372,6 @@ static void rcu_read_unlock_special(struct task_struct *t)
#ifdef CONFIG_RCU_BOOST
/* Unboost if we were boosted. */
if (special & RCU_READ_UNLOCK_BOOSTED) {
- t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_BOOSTED;
rt_mutex_unlock(t->rcu_boost_mutex);
t->rcu_boost_mutex = NULL;
}
@@ -387,13 +400,22 @@ void __rcu_read_unlock(void)
struct task_struct *t = current;
barrier(); /* needed if we ever invoke rcu_read_unlock in rcutree.c */
- --t->rcu_read_lock_nesting;
- barrier(); /* decrement before load of ->rcu_read_unlock_special */
- if (t->rcu_read_lock_nesting == 0 &&
- unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
- rcu_read_unlock_special(t);
+ if (t->rcu_read_lock_nesting != 1)
+ --t->rcu_read_lock_nesting;
+ else {
+ t->rcu_read_lock_nesting = INT_MIN;
+ barrier(); /* assign before ->rcu_read_unlock_special load */
+ if (unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
+ rcu_read_unlock_special(t);
+ barrier(); /* ->rcu_read_unlock_special load before assign */
+ t->rcu_read_lock_nesting = 0;
+ }
#ifdef CONFIG_PROVE_LOCKING
- WARN_ON_ONCE(ACCESS_ONCE(t->rcu_read_lock_nesting) < 0);
+ {
+ int rrln = ACCESS_ONCE(t->rcu_read_lock_nesting);
+
+ WARN_ON_ONCE(rrln < 0 && rrln > INT_MIN / 2);
+ }
#endif /* #ifdef CONFIG_PROVE_LOCKING */
}
EXPORT_SYMBOL_GPL(__rcu_read_unlock);
@@ -589,7 +611,8 @@ static void rcu_preempt_check_callbacks(int cpu)
rcu_preempt_qs(cpu);
return;
}
- if (per_cpu(rcu_preempt_data, cpu).qs_pending)
+ if (t->rcu_read_lock_nesting > 0 &&
+ per_cpu(rcu_preempt_data, cpu).qs_pending)
t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
}
@@ -695,9 +718,12 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp)
raw_spin_lock_irqsave(&rnp->lock, flags);
for (;;) {
- if (!sync_rcu_preempt_exp_done(rnp))
+ if (!sync_rcu_preempt_exp_done(rnp)) {
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
break;
+ }
if (rnp->parent == NULL) {
+ raw_spin_unlock_irqrestore(&rnp->lock, flags);
wake_up(&sync_rcu_preempt_exp_wq);
break;
}
@@ -707,7 +733,6 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp)
raw_spin_lock(&rnp->lock); /* irqs already disabled */
rnp->expmask &= ~mask;
}
- raw_spin_unlock_irqrestore(&rnp->lock, flags);
}
/*
@@ -1174,7 +1199,7 @@ static int rcu_boost(struct rcu_node *rnp)
t = container_of(tb, struct task_struct, rcu_node_entry);
rt_mutex_init_proxy_locked(&mtx, t);
t->rcu_boost_mutex = &mtx;
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BOOSTED;
+ t->rcu_boosted = 1;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
rt_mutex_lock(&mtx); /* Side effect: boosts task t's priority. */
rt_mutex_unlock(&mtx); /* Keep lockdep happy. */
@@ -1532,7 +1557,7 @@ static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu)
struct sched_param sp;
struct task_struct *t;
- if (!rcu_kthreads_spawnable ||
+ if (!rcu_scheduler_fully_active ||
per_cpu(rcu_cpu_kthread_task, cpu) != NULL)
return 0;
t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu);
@@ -1639,7 +1664,7 @@ static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp,
struct sched_param sp;
struct task_struct *t;
- if (!rcu_kthreads_spawnable ||
+ if (!rcu_scheduler_fully_active ||
rnp->qsmaskinit == 0)
return 0;
if (rnp->node_kthread_task == NULL) {
@@ -1665,7 +1690,7 @@ static int __init rcu_spawn_kthreads(void)
int cpu;
struct rcu_node *rnp;
- rcu_kthreads_spawnable = 1;
+ rcu_scheduler_fully_active = 1;
for_each_possible_cpu(cpu) {
per_cpu(rcu_cpu_has_work, cpu) = 0;
if (cpu_online(cpu))
@@ -1687,7 +1712,7 @@ static void __cpuinit rcu_prepare_kthreads(int cpu)
struct rcu_node *rnp = rdp->mynode;
/* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */
- if (rcu_kthreads_spawnable) {
+ if (rcu_scheduler_fully_active) {
(void)rcu_spawn_one_cpu_kthread(cpu);
if (rnp->node_kthread_task == NULL)
(void)rcu_spawn_one_node_kthread(rcu_state, rnp);
@@ -1726,6 +1751,13 @@ static void rcu_cpu_kthread_setrt(int cpu, int to_rt)
{
}
+static int __init rcu_scheduler_really_started(void)
+{
+ rcu_scheduler_fully_active = 1;
+ return 0;
+}
+early_initcall(rcu_scheduler_really_started);
+
static void __cpuinit rcu_prepare_kthreads(int cpu)
{
}
diff --git a/kernel/resource.c b/kernel/resource.c
index 798e2fae2a06..3ff40178dce7 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -38,6 +38,14 @@ struct resource iomem_resource = {
};
EXPORT_SYMBOL(iomem_resource);
+/* constraints to be met while allocating resources */
+struct resource_constraint {
+ resource_size_t min, max, align;
+ resource_size_t (*alignf)(void *, const struct resource *,
+ resource_size_t, resource_size_t);
+ void *alignf_data;
+};
+
static DEFINE_RWLOCK(resource_lock);
static void *r_next(struct seq_file *m, void *v, loff_t *pos)
@@ -384,16 +392,13 @@ static bool resource_contains(struct resource *res1, struct resource *res2)
}
/*
- * Find empty slot in the resource tree given range and alignment.
+ * Find empty slot in the resource tree with the given range and
+ * alignment constraints
*/
-static int find_resource(struct resource *root, struct resource *new,
- resource_size_t size, resource_size_t min,
- resource_size_t max, resource_size_t align,
- resource_size_t (*alignf)(void *,
- const struct resource *,
- resource_size_t,
- resource_size_t),
- void *alignf_data)
+static int __find_resource(struct resource *root, struct resource *old,
+ struct resource *new,
+ resource_size_t size,
+ struct resource_constraint *constraint)
{
struct resource *this = root->child;
struct resource tmp = *new, avail, alloc;
@@ -404,25 +409,26 @@ static int find_resource(struct resource *root, struct resource *new,
* Skip past an allocated resource that starts at 0, since the assignment
* of this->start - 1 to tmp->end below would cause an underflow.
*/
- if (this && this->start == 0) {
- tmp.start = this->end + 1;
+ if (this && this->start == root->start) {
+ tmp.start = (this == old) ? old->start : this->end + 1;
this = this->sibling;
}
for(;;) {
if (this)
- tmp.end = this->start - 1;
+ tmp.end = (this == old) ? this->end : this->start - 1;
else
tmp.end = root->end;
- resource_clip(&tmp, min, max);
+ resource_clip(&tmp, constraint->min, constraint->max);
arch_remove_reservations(&tmp);
/* Check for overflow after ALIGN() */
avail = *new;
- avail.start = ALIGN(tmp.start, align);
+ avail.start = ALIGN(tmp.start, constraint->align);
avail.end = tmp.end;
if (avail.start >= tmp.start) {
- alloc.start = alignf(alignf_data, &avail, size, align);
+ alloc.start = constraint->alignf(constraint->alignf_data, &avail,
+ size, constraint->align);
alloc.end = alloc.start + size - 1;
if (resource_contains(&avail, &alloc)) {
new->start = alloc.start;
@@ -432,14 +438,75 @@ static int find_resource(struct resource *root, struct resource *new,
}
if (!this)
break;
- tmp.start = this->end + 1;
+ if (this != old)
+ tmp.start = this->end + 1;
this = this->sibling;
}
return -EBUSY;
}
+/*
+ * Find empty slot in the resource tree given range and alignment.
+ */
+static int find_resource(struct resource *root, struct resource *new,
+ resource_size_t size,
+ struct resource_constraint *constraint)
+{
+ return __find_resource(root, NULL, new, size, constraint);
+}
+
/**
- * allocate_resource - allocate empty slot in the resource tree given range & alignment
+ * reallocate_resource - allocate a slot in the resource tree given range & alignment.
+ * The resource will be relocated if the new size cannot be reallocated in the
+ * current location.
+ *
+ * @root: root resource descriptor
+ * @old: resource descriptor desired by caller
+ * @newsize: new size of the resource descriptor
+ * @constraint: the size and alignment constraints to be met.
+ */
+int reallocate_resource(struct resource *root, struct resource *old,
+ resource_size_t newsize,
+ struct resource_constraint *constraint)
+{
+ int err=0;
+ struct resource new = *old;
+ struct resource *conflict;
+
+ write_lock(&resource_lock);
+
+ if ((err = __find_resource(root, old, &new, newsize, constraint)))
+ goto out;
+
+ if (resource_contains(&new, old)) {
+ old->start = new.start;
+ old->end = new.end;
+ goto out;
+ }
+
+ if (old->child) {
+ err = -EBUSY;
+ goto out;
+ }
+
+ if (resource_contains(old, &new)) {
+ old->start = new.start;
+ old->end = new.end;
+ } else {
+ __release_resource(old);
+ *old = new;
+ conflict = __request_resource(root, old);
+ BUG_ON(conflict);
+ }
+out:
+ write_unlock(&resource_lock);
+ return err;
+}
+
+
+/**
+ * allocate_resource - allocate empty slot in the resource tree given range & alignment.
+ * The resource will be reallocated with a new size if it was already allocated
* @root: root resource descriptor
* @new: resource descriptor desired by caller
* @size: requested resource region size
@@ -459,12 +526,25 @@ int allocate_resource(struct resource *root, struct resource *new,
void *alignf_data)
{
int err;
+ struct resource_constraint constraint;
if (!alignf)
alignf = simple_align_resource;
+ constraint.min = min;
+ constraint.max = max;
+ constraint.align = align;
+ constraint.alignf = alignf;
+ constraint.alignf_data = alignf_data;
+
+ if ( new->parent ) {
+ /* resource is already allocated, try reallocating with
+ the new constraints */
+ return reallocate_resource(root, new, size, &constraint);
+ }
+
write_lock(&resource_lock);
- err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
+ err = find_resource(root, new, size, &constraint);
if (err >= 0 && __request_resource(root, new))
err = -EBUSY;
write_unlock(&resource_lock);
diff --git a/kernel/sched.c b/kernel/sched.c
index 4380a80c1e7a..b0e7ad796d3b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -292,8 +292,8 @@ static DEFINE_SPINLOCK(task_group_lock);
* (The default weight is 1024 - so there's no practical
* limitation from this.)
*/
-#define MIN_SHARES 2
-#define MAX_SHARES (1UL << (18 + SCHED_LOAD_RESOLUTION))
+#define MIN_SHARES (1UL << 1)
+#define MAX_SHARES (1UL << 18)
static int root_task_group_load = ROOT_TASK_GROUP_LOAD;
#endif
@@ -2544,13 +2544,9 @@ static int ttwu_remote(struct task_struct *p, int wake_flags)
}
#ifdef CONFIG_SMP
-static void sched_ttwu_pending(void)
+static void sched_ttwu_do_pending(struct task_struct *list)
{
struct rq *rq = this_rq();
- struct task_struct *list = xchg(&rq->wake_list, NULL);
-
- if (!list)
- return;
raw_spin_lock(&rq->lock);
@@ -2563,9 +2559,45 @@ static void sched_ttwu_pending(void)
raw_spin_unlock(&rq->lock);
}
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void sched_ttwu_pending(void)
+{
+ struct rq *rq = this_rq();
+ struct task_struct *list = xchg(&rq->wake_list, NULL);
+
+ if (!list)
+ return;
+
+ sched_ttwu_do_pending(list);
+}
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
void scheduler_ipi(void)
{
- sched_ttwu_pending();
+ struct rq *rq = this_rq();
+ struct task_struct *list = xchg(&rq->wake_list, NULL);
+
+ if (!list)
+ return;
+
+ /*
+ * Not all reschedule IPI handlers call irq_enter/irq_exit, since
+ * traditionally all their work was done from the interrupt return
+ * path. Now that we actually do some work, we need to make sure
+ * we do call them.
+ *
+ * Some archs already do call them, luckily irq_enter/exit nest
+ * properly.
+ *
+ * Arguably we should visit all archs and update all handlers,
+ * however a fair share of IPIs are still resched only so this would
+ * somewhat pessimize the simple resched case.
+ */
+ irq_enter();
+ sched_ttwu_do_pending(list);
+ irq_exit();
}
static void ttwu_queue_remote(struct task_struct *p, int cpu)
@@ -6550,7 +6582,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
break;
}
- if (!group->cpu_power) {
+ if (!group->sgp->power) {
printk(KERN_CONT "\n");
printk(KERN_ERR "ERROR: domain->cpu_power not "
"set\n");
@@ -6574,9 +6606,9 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
printk(KERN_CONT " %s", str);
- if (group->cpu_power != SCHED_POWER_SCALE) {
+ if (group->sgp->power != SCHED_POWER_SCALE) {
printk(KERN_CONT " (cpu_power = %d)",
- group->cpu_power);
+ group->sgp->power);
}
group = group->next;
@@ -6767,11 +6799,39 @@ static struct root_domain *alloc_rootdomain(void)
return rd;
}
+static void free_sched_groups(struct sched_group *sg, int free_sgp)
+{
+ struct sched_group *tmp, *first;
+
+ if (!sg)
+ return;
+
+ first = sg;
+ do {
+ tmp = sg->next;
+
+ if (free_sgp && atomic_dec_and_test(&sg->sgp->ref))
+ kfree(sg->sgp);
+
+ kfree(sg);
+ sg = tmp;
+ } while (sg != first);
+}
+
static void free_sched_domain(struct rcu_head *rcu)
{
struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu);
- if (atomic_dec_and_test(&sd->groups->ref))
+
+ /*
+ * If its an overlapping domain it has private groups, iterate and
+ * nuke them all.
+ */
+ if (sd->flags & SD_OVERLAP) {
+ free_sched_groups(sd->groups, 1);
+ } else if (atomic_dec_and_test(&sd->groups->ref)) {
+ kfree(sd->groups->sgp);
kfree(sd->groups);
+ }
kfree(sd);
}
@@ -6938,6 +6998,7 @@ int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
struct sd_data {
struct sched_domain **__percpu sd;
struct sched_group **__percpu sg;
+ struct sched_group_power **__percpu sgp;
};
struct s_data {
@@ -6957,15 +7018,73 @@ struct sched_domain_topology_level;
typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu);
typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
+#define SDTL_OVERLAP 0x01
+
struct sched_domain_topology_level {
sched_domain_init_f init;
sched_domain_mask_f mask;
+ int flags;
struct sd_data data;
};
-/*
- * Assumes the sched_domain tree is fully constructed
- */
+static int
+build_overlap_sched_groups(struct sched_domain *sd, int cpu)
+{
+ struct sched_group *first = NULL, *last = NULL, *groups = NULL, *sg;
+ const struct cpumask *span = sched_domain_span(sd);
+ struct cpumask *covered = sched_domains_tmpmask;
+ struct sd_data *sdd = sd->private;
+ struct sched_domain *child;
+ int i;
+
+ cpumask_clear(covered);
+
+ for_each_cpu(i, span) {
+ struct cpumask *sg_span;
+
+ if (cpumask_test_cpu(i, covered))
+ continue;
+
+ sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
+ GFP_KERNEL, cpu_to_node(i));
+
+ if (!sg)
+ goto fail;
+
+ sg_span = sched_group_cpus(sg);
+
+ child = *per_cpu_ptr(sdd->sd, i);
+ if (child->child) {
+ child = child->child;
+ cpumask_copy(sg_span, sched_domain_span(child));
+ } else
+ cpumask_set_cpu(i, sg_span);
+
+ cpumask_or(covered, covered, sg_span);
+
+ sg->sgp = *per_cpu_ptr(sdd->sgp, cpumask_first(sg_span));
+ atomic_inc(&sg->sgp->ref);
+
+ if (cpumask_test_cpu(cpu, sg_span))
+ groups = sg;
+
+ if (!first)
+ first = sg;
+ if (last)
+ last->next = sg;
+ last = sg;
+ last->next = first;
+ }
+ sd->groups = groups;
+
+ return 0;
+
+fail:
+ free_sched_groups(first, 0);
+
+ return -ENOMEM;
+}
+
static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
{
struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu);
@@ -6974,24 +7093,24 @@ static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
if (child)
cpu = cpumask_first(sched_domain_span(child));
- if (sg)
+ if (sg) {
*sg = *per_cpu_ptr(sdd->sg, cpu);
+ (*sg)->sgp = *per_cpu_ptr(sdd->sgp, cpu);
+ atomic_set(&(*sg)->sgp->ref, 1); /* for claim_allocations */
+ }
return cpu;
}
/*
- * build_sched_groups takes the cpumask we wish to span, and a pointer
- * to a function which identifies what group(along with sched group) a CPU
- * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids
- * (due to the fact that we keep track of groups covered with a struct cpumask).
- *
* build_sched_groups will build a circular linked list of the groups
* covered by the given span, and will set each group's ->cpumask correctly,
* and ->cpu_power to 0.
+ *
+ * Assumes the sched_domain tree is fully constructed
*/
-static void
-build_sched_groups(struct sched_domain *sd)
+static int
+build_sched_groups(struct sched_domain *sd, int cpu)
{
struct sched_group *first = NULL, *last = NULL;
struct sd_data *sdd = sd->private;
@@ -6999,6 +7118,12 @@ build_sched_groups(struct sched_domain *sd)
struct cpumask *covered;
int i;
+ get_group(cpu, sdd, &sd->groups);
+ atomic_inc(&sd->groups->ref);
+
+ if (cpu != cpumask_first(sched_domain_span(sd)))
+ return 0;
+
lockdep_assert_held(&sched_domains_mutex);
covered = sched_domains_tmpmask;
@@ -7013,7 +7138,7 @@ build_sched_groups(struct sched_domain *sd)
continue;
cpumask_clear(sched_group_cpus(sg));
- sg->cpu_power = 0;
+ sg->sgp->power = 0;
for_each_cpu(j, span) {
if (get_group(j, sdd, NULL) != group)
@@ -7030,6 +7155,8 @@ build_sched_groups(struct sched_domain *sd)
last = sg;
}
last->next = first;
+
+ return 0;
}
/*
@@ -7044,12 +7171,17 @@ build_sched_groups(struct sched_domain *sd)
*/
static void init_sched_groups_power(int cpu, struct sched_domain *sd)
{
- WARN_ON(!sd || !sd->groups);
+ struct sched_group *sg = sd->groups;
- if (cpu != group_first_cpu(sd->groups))
- return;
+ WARN_ON(!sd || !sg);
+
+ do {
+ sg->group_weight = cpumask_weight(sched_group_cpus(sg));
+ sg = sg->next;
+ } while (sg != sd->groups);
- sd->groups->group_weight = cpumask_weight(sched_group_cpus(sd->groups));
+ if (cpu != group_first_cpu(sg))
+ return;
update_group_power(sd, cpu);
}
@@ -7170,15 +7302,15 @@ static enum s_alloc __visit_domain_allocation_hell(struct s_data *d,
static void claim_allocations(int cpu, struct sched_domain *sd)
{
struct sd_data *sdd = sd->private;
- struct sched_group *sg = sd->groups;
WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd);
*per_cpu_ptr(sdd->sd, cpu) = NULL;
- if (cpu == cpumask_first(sched_group_cpus(sg))) {
- WARN_ON_ONCE(*per_cpu_ptr(sdd->sg, cpu) != sg);
+ if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref))
*per_cpu_ptr(sdd->sg, cpu) = NULL;
- }
+
+ if (atomic_read(&(*per_cpu_ptr(sdd->sgp, cpu))->ref))
+ *per_cpu_ptr(sdd->sgp, cpu) = NULL;
}
#ifdef CONFIG_SCHED_SMT
@@ -7203,7 +7335,7 @@ static struct sched_domain_topology_level default_topology[] = {
#endif
{ sd_init_CPU, cpu_cpu_mask, },
#ifdef CONFIG_NUMA
- { sd_init_NODE, cpu_node_mask, },
+ { sd_init_NODE, cpu_node_mask, SDTL_OVERLAP, },
{ sd_init_ALLNODES, cpu_allnodes_mask, },
#endif
{ NULL, },
@@ -7227,9 +7359,14 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
if (!sdd->sg)
return -ENOMEM;
+ sdd->sgp = alloc_percpu(struct sched_group_power *);
+ if (!sdd->sgp)
+ return -ENOMEM;
+
for_each_cpu(j, cpu_map) {
struct sched_domain *sd;
struct sched_group *sg;
+ struct sched_group_power *sgp;
sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(),
GFP_KERNEL, cpu_to_node(j));
@@ -7244,6 +7381,13 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
return -ENOMEM;
*per_cpu_ptr(sdd->sg, j) = sg;
+
+ sgp = kzalloc_node(sizeof(struct sched_group_power),
+ GFP_KERNEL, cpu_to_node(j));
+ if (!sgp)
+ return -ENOMEM;
+
+ *per_cpu_ptr(sdd->sgp, j) = sgp;
}
}
@@ -7259,11 +7403,15 @@ static void __sdt_free(const struct cpumask *cpu_map)
struct sd_data *sdd = &tl->data;
for_each_cpu(j, cpu_map) {
- kfree(*per_cpu_ptr(sdd->sd, j));
+ struct sched_domain *sd = *per_cpu_ptr(sdd->sd, j);
+ if (sd && (sd->flags & SD_OVERLAP))
+ free_sched_groups(sd->groups, 0);
kfree(*per_cpu_ptr(sdd->sg, j));
+ kfree(*per_cpu_ptr(sdd->sgp, j));
}
free_percpu(sdd->sd);
free_percpu(sdd->sg);
+ free_percpu(sdd->sgp);
}
}
@@ -7309,8 +7457,13 @@ static int build_sched_domains(const struct cpumask *cpu_map,
struct sched_domain_topology_level *tl;
sd = NULL;
- for (tl = sched_domain_topology; tl->init; tl++)
+ for (tl = sched_domain_topology; tl->init; tl++) {
sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i);
+ if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP))
+ sd->flags |= SD_OVERLAP;
+ if (cpumask_equal(cpu_map, sched_domain_span(sd)))
+ break;
+ }
while (sd->child)
sd = sd->child;
@@ -7322,13 +7475,13 @@ static int build_sched_domains(const struct cpumask *cpu_map,
for_each_cpu(i, cpu_map) {
for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
sd->span_weight = cpumask_weight(sched_domain_span(sd));
- get_group(i, sd->private, &sd->groups);
- atomic_inc(&sd->groups->ref);
-
- if (i != cpumask_first(sched_domain_span(sd)))
- continue;
-
- build_sched_groups(sd);
+ if (sd->flags & SD_OVERLAP) {
+ if (build_overlap_sched_groups(sd, i))
+ goto error;
+ } else {
+ if (build_sched_groups(sd, i))
+ goto error;
+ }
}
}
@@ -7750,6 +7903,9 @@ static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq)
#endif
#endif
cfs_rq->min_vruntime = (u64)(-(1LL << 20));
+#ifndef CONFIG_64BIT
+ cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
+#endif
}
static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
@@ -8441,10 +8597,7 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
if (!tg->se[0])
return -EINVAL;
- if (shares < MIN_SHARES)
- shares = MIN_SHARES;
- else if (shares > MAX_SHARES)
- shares = MAX_SHARES;
+ shares = clamp(shares, scale_load(MIN_SHARES), scale_load(MAX_SHARES));
mutex_lock(&shares_mutex);
if (tg->shares == shares)
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index eb98f77b38ef..e7d67a9e259a 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1583,7 +1583,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
}
/* Adjust by relative CPU power of the group */
- avg_load = (avg_load * SCHED_POWER_SCALE) / group->cpu_power;
+ avg_load = (avg_load * SCHED_POWER_SCALE) / group->sgp->power;
if (local_group) {
this_load = avg_load;
@@ -2629,7 +2629,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
power >>= SCHED_POWER_SHIFT;
}
- sdg->cpu_power_orig = power;
+ sdg->sgp->power_orig = power;
if (sched_feat(ARCH_POWER))
power *= arch_scale_freq_power(sd, cpu);
@@ -2645,7 +2645,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
power = 1;
cpu_rq(cpu)->cpu_power = power;
- sdg->cpu_power = power;
+ sdg->sgp->power = power;
}
static void update_group_power(struct sched_domain *sd, int cpu)
@@ -2663,11 +2663,11 @@ static void update_group_power(struct sched_domain *sd, int cpu)
group = child->groups;
do {
- power += group->cpu_power;
+ power += group->sgp->power;
group = group->next;
} while (group != child->groups);
- sdg->cpu_power = power;
+ sdg->sgp->power = power;
}
/*
@@ -2689,7 +2689,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
/*
* If ~90% of the cpu_power is still there, we're good.
*/
- if (group->cpu_power * 32 > group->cpu_power_orig * 29)
+ if (group->sgp->power * 32 > group->sgp->power_orig * 29)
return 1;
return 0;
@@ -2769,7 +2769,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
}
/* Adjust by relative CPU power of the group */
- sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->cpu_power;
+ sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->sgp->power;
/*
* Consider the group unbalanced when the imbalance is larger
@@ -2786,7 +2786,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
if ((max_cpu_load - min_cpu_load) >= avg_load_per_task && max_nr_running > 1)
sgs->group_imb = 1;
- sgs->group_capacity = DIV_ROUND_CLOSEST(group->cpu_power,
+ sgs->group_capacity = DIV_ROUND_CLOSEST(group->sgp->power,
SCHED_POWER_SCALE);
if (!sgs->group_capacity)
sgs->group_capacity = fix_small_capacity(sd, group);
@@ -2875,7 +2875,7 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
return;
sds->total_load += sgs.group_load;
- sds->total_pwr += sg->cpu_power;
+ sds->total_pwr += sg->sgp->power;
/*
* In case the child domain prefers tasks go to siblings
@@ -2960,7 +2960,7 @@ static int check_asym_packing(struct sched_domain *sd,
if (this_cpu > busiest_cpu)
return 0;
- *imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->cpu_power,
+ *imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->sgp->power,
SCHED_POWER_SCALE);
return 1;
}
@@ -2991,7 +2991,7 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
scaled_busy_load_per_task = sds->busiest_load_per_task
* SCHED_POWER_SCALE;
- scaled_busy_load_per_task /= sds->busiest->cpu_power;
+ scaled_busy_load_per_task /= sds->busiest->sgp->power;
if (sds->max_load - sds->this_load + scaled_busy_load_per_task >=
(scaled_busy_load_per_task * imbn)) {
@@ -3005,28 +3005,28 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
* moving them.
*/
- pwr_now += sds->busiest->cpu_power *
+ pwr_now += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load);
- pwr_now += sds->this->cpu_power *
+ pwr_now += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load);
pwr_now /= SCHED_POWER_SCALE;
/* Amount of load we'd subtract */
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
- sds->busiest->cpu_power;
+ sds->busiest->sgp->power;
if (sds->max_load > tmp)
- pwr_move += sds->busiest->cpu_power *
+ pwr_move += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load - tmp);
/* Amount of load we'd add */
- if (sds->max_load * sds->busiest->cpu_power <
+ if (sds->max_load * sds->busiest->sgp->power <
sds->busiest_load_per_task * SCHED_POWER_SCALE)
- tmp = (sds->max_load * sds->busiest->cpu_power) /
- sds->this->cpu_power;
+ tmp = (sds->max_load * sds->busiest->sgp->power) /
+ sds->this->sgp->power;
else
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
- sds->this->cpu_power;
- pwr_move += sds->this->cpu_power *
+ sds->this->sgp->power;
+ pwr_move += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load + tmp);
pwr_move /= SCHED_POWER_SCALE;
@@ -3072,7 +3072,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE);
- load_above_capacity /= sds->busiest->cpu_power;
+ load_above_capacity /= sds->busiest->sgp->power;
}
/*
@@ -3088,8 +3088,8 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
max_pull = min(sds->max_load - sds->avg_load, load_above_capacity);
/* How much load to actually move to equalise the imbalance */
- *imbalance = min(max_pull * sds->busiest->cpu_power,
- (sds->avg_load - sds->this_load) * sds->this->cpu_power)
+ *imbalance = min(max_pull * sds->busiest->sgp->power,
+ (sds->avg_load - sds->this_load) * sds->this->sgp->power)
/ SCHED_POWER_SCALE;
/*
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index be40f7371ee1..1e7066d76c26 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -70,3 +70,5 @@ SCHED_FEAT(NONIRQ_POWER, 1)
* using the scheduler IPI. Reduces rq->lock contention/bounces.
*/
SCHED_FEAT(TTWU_QUEUE, 1)
+
+SCHED_FEAT(FORCE_SD_OVERLAP, 0)
diff --git a/kernel/signal.c b/kernel/signal.c
index ff7678603328..415d85d6f6c6 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1178,18 +1178,25 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
{
struct sighand_struct *sighand;
- rcu_read_lock();
for (;;) {
+ local_irq_save(*flags);
+ rcu_read_lock();
sighand = rcu_dereference(tsk->sighand);
- if (unlikely(sighand == NULL))
+ if (unlikely(sighand == NULL)) {
+ rcu_read_unlock();
+ local_irq_restore(*flags);
break;
+ }
- spin_lock_irqsave(&sighand->siglock, *flags);
- if (likely(sighand == tsk->sighand))
+ spin_lock(&sighand->siglock);
+ if (likely(sighand == tsk->sighand)) {
+ rcu_read_unlock();
break;
- spin_unlock_irqrestore(&sighand->siglock, *flags);
+ }
+ spin_unlock(&sighand->siglock);
+ rcu_read_unlock();
+ local_irq_restore(*flags);
}
- rcu_read_unlock();
return sighand;
}
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 40cf63ddd4b3..fca82c32042b 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -315,16 +315,24 @@ static inline void invoke_softirq(void)
{
if (!force_irqthreads)
__do_softirq();
- else
+ else {
+ __local_bh_disable((unsigned long)__builtin_return_address(0),
+ SOFTIRQ_OFFSET);
wakeup_softirqd();
+ __local_bh_enable(SOFTIRQ_OFFSET);
+ }
}
#else
static inline void invoke_softirq(void)
{
if (!force_irqthreads)
do_softirq();
- else
+ else {
+ __local_bh_disable((unsigned long)__builtin_return_address(0),
+ SOFTIRQ_OFFSET);
wakeup_softirqd();
+ __local_bh_enable(SOFTIRQ_OFFSET);
+ }
}
#endif