summaryrefslogtreecommitdiffstats
path: root/include/linux
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/init_task.h5
-rw-r--r--include/linux/sched.h105
-rw-r--r--include/linux/wait.h17
3 files changed, 94 insertions, 33 deletions
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 696d22312b31..bb9b075f0eb0 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -50,9 +50,8 @@ extern struct fs_struct init_fs;
.cpu_timers = INIT_CPU_TIMERS(sig.cpu_timers), \
.rlim = INIT_RLIMITS, \
.cputimer = { \
- .cputime = INIT_CPUTIME, \
- .running = 0, \
- .lock = __RAW_SPIN_LOCK_UNLOCKED(sig.cputimer.lock), \
+ .cputime_atomic = INIT_CPUTIME_ATOMIC, \
+ .running = 0, \
}, \
.cred_guard_mutex = \
__MUTEX_INITIALIZER(sig.cred_guard_mutex), \
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 26a2e6122734..5f8defa155cf 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -173,7 +173,12 @@ extern unsigned long nr_iowait_cpu(int cpu);
extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
extern void calc_global_load(unsigned long ticks);
+
+#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
extern void update_cpu_load_nohz(void);
+#else
+static inline void update_cpu_load_nohz(void) { }
+#endif
extern unsigned long get_parent_ip(unsigned long addr);
@@ -567,6 +572,23 @@ struct task_cputime {
.sum_exec_runtime = 0, \
}
+/*
+ * This is the atomic variant of task_cputime, which can be used for
+ * storing and updating task_cputime statistics without locking.
+ */
+struct task_cputime_atomic {
+ atomic64_t utime;
+ atomic64_t stime;
+ atomic64_t sum_exec_runtime;
+};
+
+#define INIT_CPUTIME_ATOMIC \
+ (struct task_cputime_atomic) { \
+ .utime = ATOMIC64_INIT(0), \
+ .stime = ATOMIC64_INIT(0), \
+ .sum_exec_runtime = ATOMIC64_INIT(0), \
+ }
+
#ifdef CONFIG_PREEMPT_COUNT
#define PREEMPT_DISABLED (1 + PREEMPT_ENABLED)
#else
@@ -584,18 +606,16 @@ struct task_cputime {
/**
* struct thread_group_cputimer - thread group interval timer counts
- * @cputime: thread group interval timers.
+ * @cputime_atomic: atomic thread group interval timers.
* @running: non-zero when there are timers running and
* @cputime receives updates.
- * @lock: lock for fields in this struct.
*
* This structure contains the version of task_cputime, above, that is
* used for thread group CPU timer calculations.
*/
struct thread_group_cputimer {
- struct task_cputime cputime;
+ struct task_cputime_atomic cputime_atomic;
int running;
- raw_spinlock_t lock;
};
#include <linux/rwsem.h>
@@ -900,6 +920,50 @@ enum cpu_idle_type {
#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
/*
+ * Wake-queues are lists of tasks with a pending wakeup, whose
+ * callers have already marked the task as woken internally,
+ * and can thus carry on. A common use case is being able to
+ * do the wakeups once the corresponding user lock as been
+ * released.
+ *
+ * We hold reference to each task in the list across the wakeup,
+ * thus guaranteeing that the memory is still valid by the time
+ * the actual wakeups are performed in wake_up_q().
+ *
+ * One per task suffices, because there's never a need for a task to be
+ * in two wake queues simultaneously; it is forbidden to abandon a task
+ * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
+ * already in a wake queue, the wakeup will happen soon and the second
+ * waker can just skip it.
+ *
+ * The WAKE_Q macro declares and initializes the list head.
+ * wake_up_q() does NOT reinitialize the list; it's expected to be
+ * called near the end of a function, where the fact that the queue is
+ * not used again will be easy to see by inspection.
+ *
+ * Note that this can cause spurious wakeups. schedule() callers
+ * must ensure the call is done inside a loop, confirming that the
+ * wakeup condition has in fact occurred.
+ */
+struct wake_q_node {
+ struct wake_q_node *next;
+};
+
+struct wake_q_head {
+ struct wake_q_node *first;
+ struct wake_q_node **lastp;
+};
+
+#define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
+
+#define WAKE_Q(name) \
+ struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
+
+extern void wake_q_add(struct wake_q_head *head,
+ struct task_struct *task);
+extern void wake_up_q(struct wake_q_head *head);
+
+/*
* sched-domains (multiprocessor balancing) declarations:
*/
#ifdef CONFIG_SMP
@@ -1334,8 +1398,6 @@ struct task_struct {
int rcu_read_lock_nesting;
union rcu_special rcu_read_unlock_special;
struct list_head rcu_node_entry;
-#endif /* #ifdef CONFIG_PREEMPT_RCU */
-#ifdef CONFIG_PREEMPT_RCU
struct rcu_node *rcu_blocked_node;
#endif /* #ifdef CONFIG_PREEMPT_RCU */
#ifdef CONFIG_TASKS_RCU
@@ -1369,7 +1431,7 @@ struct task_struct {
int exit_state;
int exit_code, exit_signal;
int pdeath_signal; /* The signal sent when the parent dies */
- unsigned int jobctl; /* JOBCTL_*, siglock protected */
+ unsigned long jobctl; /* JOBCTL_*, siglock protected */
/* Used for emulating ABI behavior of previous Linux versions */
unsigned int personality;
@@ -1511,6 +1573,8 @@ struct task_struct {
/* Protection of the PI data structures: */
raw_spinlock_t pi_lock;
+ struct wake_q_node wake_q;
+
#ifdef CONFIG_RT_MUTEXES
/* PI waiters blocked on a rt_mutex held by this task */
struct rb_root pi_waiters;
@@ -2077,22 +2141,22 @@ TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */
#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */
-#define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT)
-#define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT)
-#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT)
-#define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT)
-#define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT)
-#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT)
-#define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT)
+#define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT)
+#define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT)
+#define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT)
+#define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT)
+#define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT)
+#define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT)
+#define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT)
#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
extern bool task_set_jobctl_pending(struct task_struct *task,
- unsigned int mask);
+ unsigned long mask);
extern void task_clear_jobctl_trapping(struct task_struct *task);
extern void task_clear_jobctl_pending(struct task_struct *task,
- unsigned int mask);
+ unsigned long mask);
static inline void rcu_copy_process(struct task_struct *p)
{
@@ -2962,11 +3026,6 @@ static __always_inline bool need_resched(void)
void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
-static inline void thread_group_cputime_init(struct signal_struct *sig)
-{
- raw_spin_lock_init(&sig->cputimer.lock);
-}
-
/*
* Reevaluate whether the task has signals pending delivery.
* Wake the task if so.
@@ -3080,13 +3139,13 @@ static inline void mm_update_next_owner(struct mm_struct *mm)
static inline unsigned long task_rlimit(const struct task_struct *tsk,
unsigned int limit)
{
- return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
+ return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
}
static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
unsigned int limit)
{
- return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
+ return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
}
static inline unsigned long rlimit(unsigned int limit)
diff --git a/include/linux/wait.h b/include/linux/wait.h
index 2db83349865b..d69ac4ecc88b 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -969,7 +969,7 @@ extern int bit_wait_io_timeout(struct wait_bit_key *);
* on that signal.
*/
static inline int
-wait_on_bit(void *word, int bit, unsigned mode)
+wait_on_bit(unsigned long *word, int bit, unsigned mode)
{
might_sleep();
if (!test_bit(bit, word))
@@ -994,7 +994,7 @@ wait_on_bit(void *word, int bit, unsigned mode)
* on that signal.
*/
static inline int
-wait_on_bit_io(void *word, int bit, unsigned mode)
+wait_on_bit_io(unsigned long *word, int bit, unsigned mode)
{
might_sleep();
if (!test_bit(bit, word))
@@ -1020,7 +1020,8 @@ wait_on_bit_io(void *word, int bit, unsigned mode)
* received a signal and the mode permitted wakeup on that signal.
*/
static inline int
-wait_on_bit_timeout(void *word, int bit, unsigned mode, unsigned long timeout)
+wait_on_bit_timeout(unsigned long *word, int bit, unsigned mode,
+ unsigned long timeout)
{
might_sleep();
if (!test_bit(bit, word))
@@ -1047,7 +1048,8 @@ wait_on_bit_timeout(void *word, int bit, unsigned mode, unsigned long timeout)
* on that signal.
*/
static inline int
-wait_on_bit_action(void *word, int bit, wait_bit_action_f *action, unsigned mode)
+wait_on_bit_action(unsigned long *word, int bit, wait_bit_action_f *action,
+ unsigned mode)
{
might_sleep();
if (!test_bit(bit, word))
@@ -1075,7 +1077,7 @@ wait_on_bit_action(void *word, int bit, wait_bit_action_f *action, unsigned mode
* the @mode allows that signal to wake the process.
*/
static inline int
-wait_on_bit_lock(void *word, int bit, unsigned mode)
+wait_on_bit_lock(unsigned long *word, int bit, unsigned mode)
{
might_sleep();
if (!test_and_set_bit(bit, word))
@@ -1099,7 +1101,7 @@ wait_on_bit_lock(void *word, int bit, unsigned mode)
* the @mode allows that signal to wake the process.
*/
static inline int
-wait_on_bit_lock_io(void *word, int bit, unsigned mode)
+wait_on_bit_lock_io(unsigned long *word, int bit, unsigned mode)
{
might_sleep();
if (!test_and_set_bit(bit, word))
@@ -1125,7 +1127,8 @@ wait_on_bit_lock_io(void *word, int bit, unsigned mode)
* the @mode allows that signal to wake the process.
*/
static inline int
-wait_on_bit_lock_action(void *word, int bit, wait_bit_action_f *action, unsigned mode)
+wait_on_bit_lock_action(unsigned long *word, int bit, wait_bit_action_f *action,
+ unsigned mode)
{
might_sleep();
if (!test_and_set_bit(bit, word))
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-19 23:27:43 +0200