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-rw-r--r--kernel/cgroup.c110
-rw-r--r--kernel/fork.c4
-rw-r--r--kernel/irq/chip.c33
-rw-r--r--kernel/irq/handle.c4
-rw-r--r--kernel/irq/internals.h2
-rw-r--r--kernel/irq/irqdesc.c20
-rw-r--r--kernel/irq/irqdomain.c1
-rw-r--r--kernel/irq/manage.c12
-rw-r--r--kernel/irq/proc.c2
-rw-r--r--kernel/irq/resend.c2
-rw-r--r--kernel/locking/lockdep.c10
-rw-r--r--kernel/sched/core.c15
-rw-r--r--kernel/sched/wait.c7
13 files changed, 142 insertions, 80 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2cf0f79f1fc90..2c9eae6ad9704 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -46,7 +46,6 @@
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/rwsem.h>
-#include <linux/percpu-rwsem.h>
#include <linux/string.h>
#include <linux/sort.h>
#include <linux/kmod.h>
@@ -104,8 +103,6 @@ static DEFINE_SPINLOCK(cgroup_idr_lock);
*/
static DEFINE_SPINLOCK(release_agent_path_lock);
-struct percpu_rw_semaphore cgroup_threadgroup_rwsem;
-
#define cgroup_assert_mutex_or_rcu_locked() \
RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \
!lockdep_is_held(&cgroup_mutex), \
@@ -874,6 +871,48 @@ static struct css_set *find_css_set(struct css_set *old_cset,
return cset;
}
+void cgroup_threadgroup_change_begin(struct task_struct *tsk)
+{
+ down_read(&tsk->signal->group_rwsem);
+}
+
+void cgroup_threadgroup_change_end(struct task_struct *tsk)
+{
+ up_read(&tsk->signal->group_rwsem);
+}
+
+/**
+ * threadgroup_lock - lock threadgroup
+ * @tsk: member task of the threadgroup to lock
+ *
+ * Lock the threadgroup @tsk belongs to. No new task is allowed to enter
+ * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or
+ * change ->group_leader/pid. This is useful for cases where the threadgroup
+ * needs to stay stable across blockable operations.
+ *
+ * fork and exit explicitly call threadgroup_change_{begin|end}() for
+ * synchronization. While held, no new task will be added to threadgroup
+ * and no existing live task will have its PF_EXITING set.
+ *
+ * de_thread() does threadgroup_change_{begin|end}() when a non-leader
+ * sub-thread becomes a new leader.
+ */
+static void threadgroup_lock(struct task_struct *tsk)
+{
+ down_write(&tsk->signal->group_rwsem);
+}
+
+/**
+ * threadgroup_unlock - unlock threadgroup
+ * @tsk: member task of the threadgroup to unlock
+ *
+ * Reverse threadgroup_lock().
+ */
+static inline void threadgroup_unlock(struct task_struct *tsk)
+{
+ up_write(&tsk->signal->group_rwsem);
+}
+
static struct cgroup_root *cgroup_root_from_kf(struct kernfs_root *kf_root)
{
struct cgroup *root_cgrp = kf_root->kn->priv;
@@ -2074,9 +2113,9 @@ static void cgroup_task_migrate(struct cgroup *old_cgrp,
lockdep_assert_held(&css_set_rwsem);
/*
- * We are synchronized through cgroup_threadgroup_rwsem against
- * PF_EXITING setting such that we can't race against cgroup_exit()
- * changing the css_set to init_css_set and dropping the old one.
+ * We are synchronized through threadgroup_lock() against PF_EXITING
+ * setting such that we can't race against cgroup_exit() changing the
+ * css_set to init_css_set and dropping the old one.
*/
WARN_ON_ONCE(tsk->flags & PF_EXITING);
old_cset = task_css_set(tsk);
@@ -2133,11 +2172,10 @@ static void cgroup_migrate_finish(struct list_head *preloaded_csets)
* @src_cset and add it to @preloaded_csets, which should later be cleaned
* up by cgroup_migrate_finish().
*
- * This function may be called without holding cgroup_threadgroup_rwsem
- * even if the target is a process. Threads may be created and destroyed
- * but as long as cgroup_mutex is not dropped, no new css_set can be put
- * into play and the preloaded css_sets are guaranteed to cover all
- * migrations.
+ * This function may be called without holding threadgroup_lock even if the
+ * target is a process. Threads may be created and destroyed but as long
+ * as cgroup_mutex is not dropped, no new css_set can be put into play and
+ * the preloaded css_sets are guaranteed to cover all migrations.
*/
static void cgroup_migrate_add_src(struct css_set *src_cset,
struct cgroup *dst_cgrp,
@@ -2240,7 +2278,7 @@ err:
* @threadgroup: whether @leader points to the whole process or a single task
*
* Migrate a process or task denoted by @leader to @cgrp. If migrating a
- * process, the caller must be holding cgroup_threadgroup_rwsem. The
+ * process, the caller must be holding threadgroup_lock of @leader. The
* caller is also responsible for invoking cgroup_migrate_add_src() and
* cgroup_migrate_prepare_dst() on the targets before invoking this
* function and following up with cgroup_migrate_finish().
@@ -2368,7 +2406,7 @@ out_release_tset:
* @leader: the task or the leader of the threadgroup to be attached
* @threadgroup: attach the whole threadgroup?
*
- * Call holding cgroup_mutex and cgroup_threadgroup_rwsem.
+ * Call holding cgroup_mutex and threadgroup_lock of @leader.
*/
static int cgroup_attach_task(struct cgroup *dst_cgrp,
struct task_struct *leader, bool threadgroup)
@@ -2460,13 +2498,14 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf,
if (!cgrp)
return -ENODEV;
- percpu_down_write(&cgroup_threadgroup_rwsem);
+retry_find_task:
rcu_read_lock();
if (pid) {
tsk = find_task_by_vpid(pid);
if (!tsk) {
+ rcu_read_unlock();
ret = -ESRCH;
- goto out_unlock_rcu;
+ goto out_unlock_cgroup;
}
} else {
tsk = current;
@@ -2482,23 +2521,37 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf,
*/
if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) {
ret = -EINVAL;
- goto out_unlock_rcu;
+ rcu_read_unlock();
+ goto out_unlock_cgroup;
}
get_task_struct(tsk);
rcu_read_unlock();
+ threadgroup_lock(tsk);
+ if (threadgroup) {
+ if (!thread_group_leader(tsk)) {
+ /*
+ * a race with de_thread from another thread's exec()
+ * may strip us of our leadership, if this happens,
+ * there is no choice but to throw this task away and
+ * try again; this is
+ * "double-double-toil-and-trouble-check locking".
+ */
+ threadgroup_unlock(tsk);
+ put_task_struct(tsk);
+ goto retry_find_task;
+ }
+ }
+
ret = cgroup_procs_write_permission(tsk, cgrp, of);
if (!ret)
ret = cgroup_attach_task(cgrp, tsk, threadgroup);
- put_task_struct(tsk);
- goto out_unlock_threadgroup;
+ threadgroup_unlock(tsk);
-out_unlock_rcu:
- rcu_read_unlock();
-out_unlock_threadgroup:
- percpu_up_write(&cgroup_threadgroup_rwsem);
+ put_task_struct(tsk);
+out_unlock_cgroup:
cgroup_kn_unlock(of->kn);
return ret ?: nbytes;
}
@@ -2643,8 +2696,6 @@ static int cgroup_update_dfl_csses(struct cgroup *cgrp)
lockdep_assert_held(&cgroup_mutex);
- percpu_down_write(&cgroup_threadgroup_rwsem);
-
/* look up all csses currently attached to @cgrp's subtree */
down_read(&css_set_rwsem);
css_for_each_descendant_pre(css, cgroup_css(cgrp, NULL)) {
@@ -2700,8 +2751,17 @@ static int cgroup_update_dfl_csses(struct cgroup *cgrp)
goto out_finish;
last_task = task;
+ threadgroup_lock(task);
+ /* raced against de_thread() from another thread? */
+ if (!thread_group_leader(task)) {
+ threadgroup_unlock(task);
+ put_task_struct(task);
+ continue;
+ }
+
ret = cgroup_migrate(src_cset->dfl_cgrp, task, true);
+ threadgroup_unlock(task);
put_task_struct(task);
if (WARN(ret, "cgroup: failed to update controllers for the default hierarchy (%d), further operations may crash or hang\n", ret))
@@ -2711,7 +2771,6 @@ static int cgroup_update_dfl_csses(struct cgroup *cgrp)
out_finish:
cgroup_migrate_finish(&preloaded_csets);
- percpu_up_write(&cgroup_threadgroup_rwsem);
return ret;
}
@@ -5024,7 +5083,6 @@ int __init cgroup_init(void)
unsigned long key;
int ssid, err;
- BUG_ON(percpu_init_rwsem(&cgroup_threadgroup_rwsem));
BUG_ON(cgroup_init_cftypes(NULL, cgroup_dfl_base_files));
BUG_ON(cgroup_init_cftypes(NULL, cgroup_legacy_base_files));
diff --git a/kernel/fork.c b/kernel/fork.c
index 7d5f0f118a634..2845623fb5826 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1149,6 +1149,10 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
tty_audit_fork(sig);
sched_autogroup_fork(sig);
+#ifdef CONFIG_CGROUPS
+ init_rwsem(&sig->group_rwsem);
+#endif
+
sig->oom_score_adj = current->signal->oom_score_adj;
sig->oom_score_adj_min = current->signal->oom_score_adj_min;
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 6e40a9539763f..e28169dd1c36a 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -83,7 +83,7 @@ int irq_set_handler_data(unsigned int irq, void *data)
if (!desc)
return -EINVAL;
- desc->irq_data.handler_data = data;
+ desc->irq_common_data.handler_data = data;
irq_put_desc_unlock(desc, flags);
return 0;
}
@@ -105,7 +105,7 @@ int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
if (!desc)
return -EINVAL;
- desc->irq_data.msi_desc = entry;
+ desc->irq_common_data.msi_desc = entry;
if (entry && !irq_offset)
entry->irq = irq_base;
irq_put_desc_unlock(desc, flags);
@@ -372,7 +372,6 @@ static bool irq_may_run(struct irq_desc *desc)
/**
* handle_simple_irq - Simple and software-decoded IRQs.
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Simple interrupts are either sent from a demultiplexing interrupt
@@ -382,8 +381,7 @@ static bool irq_may_run(struct irq_desc *desc)
* Note: The caller is expected to handle the ack, clear, mask and
* unmask issues if necessary.
*/
-void
-handle_simple_irq(unsigned int irq, struct irq_desc *desc)
+void handle_simple_irq(struct irq_desc *desc)
{
raw_spin_lock(&desc->lock);
@@ -425,7 +423,6 @@ static void cond_unmask_irq(struct irq_desc *desc)
/**
* handle_level_irq - Level type irq handler
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Level type interrupts are active as long as the hardware line has
@@ -433,8 +430,7 @@ static void cond_unmask_irq(struct irq_desc *desc)
* it after the associated handler has acknowledged the device, so the
* interrupt line is back to inactive.
*/
-void
-handle_level_irq(unsigned int irq, struct irq_desc *desc)
+void handle_level_irq(struct irq_desc *desc)
{
raw_spin_lock(&desc->lock);
mask_ack_irq(desc);
@@ -496,7 +492,6 @@ static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
/**
* handle_fasteoi_irq - irq handler for transparent controllers
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Only a single callback will be issued to the chip: an ->eoi()
@@ -504,8 +499,7 @@ static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
* for modern forms of interrupt handlers, which handle the flow
* details in hardware, transparently.
*/
-void
-handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
+void handle_fasteoi_irq(struct irq_desc *desc)
{
struct irq_chip *chip = desc->irq_data.chip;
@@ -546,7 +540,6 @@ EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
/**
* handle_edge_irq - edge type IRQ handler
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Interrupt occures on the falling and/or rising edge of a hardware
@@ -560,8 +553,7 @@ EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
* the handler was running. If all pending interrupts are handled, the
* loop is left.
*/
-void
-handle_edge_irq(unsigned int irq, struct irq_desc *desc)
+void handle_edge_irq(struct irq_desc *desc)
{
raw_spin_lock(&desc->lock);
@@ -618,13 +610,12 @@ EXPORT_SYMBOL(handle_edge_irq);
#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
/**
* handle_edge_eoi_irq - edge eoi type IRQ handler
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Similar as the above handle_edge_irq, but using eoi and w/o the
* mask/unmask logic.
*/
-void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
+void handle_edge_eoi_irq(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
@@ -665,13 +656,11 @@ out_eoi:
/**
* handle_percpu_irq - Per CPU local irq handler
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Per CPU interrupts on SMP machines without locking requirements
*/
-void
-handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
+void handle_percpu_irq(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
@@ -688,7 +677,6 @@ handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
/**
* handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
- * @irq: the interrupt number
* @desc: the interrupt description structure for this irq
*
* Per CPU interrupts on SMP machines without locking requirements. Same as
@@ -698,11 +686,12 @@ handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
* contain the real device id for the cpu on which this handler is
* called
*/
-void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
+void handle_percpu_devid_irq(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
struct irqaction *action = desc->action;
void *dev_id = raw_cpu_ptr(action->percpu_dev_id);
+ unsigned int irq = irq_desc_get_irq(desc);
irqreturn_t res;
kstat_incr_irqs_this_cpu(desc);
@@ -796,7 +785,7 @@ irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
return;
__irq_do_set_handler(desc, handle, 1, NULL);
- desc->irq_data.handler_data = data;
+ desc->irq_common_data.handler_data = data;
irq_put_desc_busunlock(desc, flags);
}
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index b6eeea8a80c5b..de41a68fc038d 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -27,8 +27,10 @@
*
* Handles spurious and unhandled IRQ's. It also prints a debugmessage.
*/
-void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
+void handle_bad_irq(struct irq_desc *desc)
{
+ unsigned int irq = irq_desc_get_irq(desc);
+
print_irq_desc(irq, desc);
kstat_incr_irqs_this_cpu(desc);
ack_bad_irq(irq);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index eee4b385cffb4..5ef0c2dbe9302 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -194,7 +194,7 @@ static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc)
static inline int irq_desc_get_node(struct irq_desc *desc)
{
- return irq_data_get_node(&desc->irq_data);
+ return irq_common_data_get_node(&desc->irq_common_data);
}
#ifdef CONFIG_PM_SLEEP
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 0a2a4b697bcbf..239e2ae2c947d 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -38,12 +38,13 @@ static void __init init_irq_default_affinity(void)
#ifdef CONFIG_SMP
static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
{
- if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
+ if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
+ gfp, node))
return -ENOMEM;
#ifdef CONFIG_GENERIC_PENDING_IRQ
if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
- free_cpumask_var(desc->irq_data.affinity);
+ free_cpumask_var(desc->irq_common_data.affinity);
return -ENOMEM;
}
#endif
@@ -52,11 +53,13 @@ static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
static void desc_smp_init(struct irq_desc *desc, int node)
{
- desc->irq_data.node = node;
- cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
+ cpumask_copy(desc->irq_common_data.affinity, irq_default_affinity);
#ifdef CONFIG_GENERIC_PENDING_IRQ
cpumask_clear(desc->pending_mask);
#endif
+#ifdef CONFIG_NUMA
+ desc->irq_common_data.node = node;
+#endif
}
#else
@@ -70,12 +73,13 @@ static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
{
int cpu;
+ desc->irq_common_data.handler_data = NULL;
+ desc->irq_common_data.msi_desc = NULL;
+
desc->irq_data.common = &desc->irq_common_data;
desc->irq_data.irq = irq;
desc->irq_data.chip = &no_irq_chip;
desc->irq_data.chip_data = NULL;
- desc->irq_data.handler_data = NULL;
- desc->irq_data.msi_desc = NULL;
irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
desc->handle_irq = handle_bad_irq;
@@ -121,7 +125,7 @@ static void free_masks(struct irq_desc *desc)
#ifdef CONFIG_GENERIC_PENDING_IRQ
free_cpumask_var(desc->pending_mask);
#endif
- free_cpumask_var(desc->irq_data.affinity);
+ free_cpumask_var(desc->irq_common_data.affinity);
}
#else
static inline void free_masks(struct irq_desc *desc) { }
@@ -343,7 +347,7 @@ int generic_handle_irq(unsigned int irq)
if (!desc)
return -EINVAL;
- generic_handle_irq_desc(irq, desc);
+ generic_handle_irq_desc(desc);
return 0;
}
EXPORT_SYMBOL_GPL(generic_handle_irq);
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 79baaf8a7813a..dc9d27c0c1589 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -844,7 +844,6 @@ static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain,
child->parent_data = irq_data;
irq_data->irq = child->irq;
irq_data->common = child->common;
- irq_data->node = child->node;
irq_data->domain = domain;
}
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index ad1b064f94fee..f9a59f6cabd2d 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -192,7 +192,7 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
switch (ret) {
case IRQ_SET_MASK_OK:
case IRQ_SET_MASK_OK_DONE:
- cpumask_copy(data->affinity, mask);
+ cpumask_copy(desc->irq_common_data.affinity, mask);
case IRQ_SET_MASK_OK_NOCOPY:
irq_set_thread_affinity(desc);
ret = 0;
@@ -304,7 +304,7 @@ static void irq_affinity_notify(struct work_struct *work)
if (irq_move_pending(&desc->irq_data))
irq_get_pending(cpumask, desc);
else
- cpumask_copy(cpumask, desc->irq_data.affinity);
+ cpumask_copy(cpumask, desc->irq_common_data.affinity);
raw_spin_unlock_irqrestore(&desc->lock, flags);
notify->notify(notify, cpumask);
@@ -375,9 +375,9 @@ static int setup_affinity(struct irq_desc *desc, struct cpumask *mask)
* one of the targets is online.
*/
if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
- if (cpumask_intersects(desc->irq_data.affinity,
+ if (cpumask_intersects(desc->irq_common_data.affinity,
cpu_online_mask))
- set = desc->irq_data.affinity;
+ set = desc->irq_common_data.affinity;
else
irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
}
@@ -829,8 +829,8 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
* This code is triggered unconditionally. Check the affinity
* mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
*/
- if (desc->irq_data.affinity)
- cpumask_copy(mask, desc->irq_data.affinity);
+ if (desc->irq_common_data.affinity)
+ cpumask_copy(mask, desc->irq_common_data.affinity);
else
valid = false;
raw_spin_unlock_irq(&desc->lock);
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 0e97c142ce402..e3a8c9577ba64 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -39,7 +39,7 @@ static struct proc_dir_entry *root_irq_dir;
static int show_irq_affinity(int type, struct seq_file *m, void *v)
{
struct irq_desc *desc = irq_to_desc((long)m->private);
- const struct cpumask *mask = desc->irq_data.affinity;
+ const struct cpumask *mask = desc->irq_common_data.affinity;
#ifdef CONFIG_GENERIC_PENDING_IRQ
if (irqd_is_setaffinity_pending(&desc->irq_data))
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index dd95f44f99b22..b86886beee4f2 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -38,7 +38,7 @@ static void resend_irqs(unsigned long arg)
clear_bit(irq, irqs_resend);
desc = irq_to_desc(irq);
local_irq_disable();
- desc->handle_irq(irq, desc);
+ desc->handle_irq(desc);
local_irq_enable();
}
}
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 8acfbf773e062..4e49cc4c9952c 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -3068,7 +3068,7 @@ static int __lock_is_held(struct lockdep_map *lock);
static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
int trylock, int read, int check, int hardirqs_off,
struct lockdep_map *nest_lock, unsigned long ip,
- int references)
+ int references, int pin_count)
{
struct task_struct *curr = current;
struct lock_class *class = NULL;
@@ -3157,7 +3157,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
hlock->waittime_stamp = 0;
hlock->holdtime_stamp = lockstat_clock();
#endif
- hlock->pin_count = 0;
+ hlock->pin_count = pin_count;
if (check && !mark_irqflags(curr, hlock))
return 0;
@@ -3343,7 +3343,7 @@ found_it:
hlock_class(hlock)->subclass, hlock->trylock,
hlock->read, hlock->check, hlock->hardirqs_off,
hlock->nest_lock, hlock->acquire_ip,
- hlock->references))
+ hlock->references, hlock->pin_count))
return 0;
}
@@ -3433,7 +3433,7 @@ found_it:
hlock_class(hlock)->subclass, hlock->trylock,
hlock->read, hlock->check, hlock->hardirqs_off,
hlock->nest_lock, hlock->acquire_ip,
- hlock->references))
+ hlock->references, hlock->pin_count))
return 0;
}
@@ -3583,7 +3583,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
current->lockdep_recursion = 1;
trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip);
__lock_acquire(lock, subclass, trylock, read, check,
- irqs_disabled_flags(flags), nest_lock, ip, 0);
+ irqs_disabled_flags(flags), nest_lock, ip, 0, 0);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f0d043ec0182f..6159531419517 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2669,13 +2669,20 @@ unsigned long nr_running(void)
/*
* Check if only the current task is running on the cpu.
+ *
+ * Caution: this function does not check that the caller has disabled
+ * preemption, thus the result might have a time-of-check-to-time-of-use
+ * race. The caller is responsible to use it correctly, for example:
+ *
+ * - from a non-preemptable section (of course)
+ *
+ * - from a thread that is bound to a single CPU
+ *
+ * - in a loop with very short iterations (e.g. a polling loop)
*/
bool single_task_running(void)
{
- if (cpu_rq(smp_processor_id())->nr_running == 1)
- return true;
- else
- return false;
+ return raw_rq()->nr_running == 1;
}
EXPORT_SYMBOL(single_task_running);
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 272d9322bc5df..052e02672d124 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -106,10 +106,9 @@ void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr)
}
EXPORT_SYMBOL_GPL(__wake_up_locked);
-void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, int nr,
- void *key)
+void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key)
{
- __wake_up_common(q, mode, nr, 0, key);
+ __wake_up_common(q, mode, 1, 0, key);
}
EXPORT_SYMBOL_GPL(__wake_up_locked_key);
@@ -284,7 +283,7 @@ void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait,
if (!list_empty(&wait->task_list))
list_del_init(&wait->task_list);
else if (waitqueue_active(q))
- __wake_up_locked_key(q, mode, 1, key);
+ __wake_up_locked_key(q, mode, key);
spin_unlock_irqrestore(&q->lock, flags);
}
EXPORT_SYMBOL(abort_exclusive_wait);
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-15 19:26:16 +0000