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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
commite5fd91f1ef340da553f7a79da9540c3db711c937 (patch)
treeb11842027dc6641da63f4bcc524f8678263304a3 /include/linux/sched.h
parent2a9b0348e685a63d97486f6749622b61e9e3292f (diff)
Linux-libre 4.2-gnu
Diffstat (limited to 'include/linux/sched.h')
-rw-r--r--include/linux/sched.h337
1 files changed, 159 insertions, 178 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 5083de9c1..04b5ada46 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -25,7 +25,7 @@ struct sched_param {
#include <linux/errno.h>
#include <linux/nodemask.h>
#include <linux/mm_types.h>
-#include <linux/preempt_mask.h>
+#include <linux/preempt.h>
#include <asm/page.h>
#include <asm/ptrace.h>
@@ -58,6 +58,7 @@ struct sched_param {
#include <linux/uidgid.h>
#include <linux/gfp.h>
#include <linux/magic.h>
+#include <linux/cgroup-defs.h>
#include <asm/processor.h>
@@ -132,6 +133,7 @@ struct fs_struct;
struct perf_event_context;
struct blk_plug;
struct filename;
+struct nameidata;
#define VMACACHE_BITS 2
#define VMACACHE_SIZE (1U << VMACACHE_BITS)
@@ -173,7 +175,12 @@ 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);
@@ -185,8 +192,6 @@ struct task_group;
#ifdef CONFIG_SCHED_DEBUG
extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
extern void proc_sched_set_task(struct task_struct *p);
-extern void
-print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
#endif
/*
@@ -213,9 +218,10 @@ print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
#define TASK_WAKEKILL 128
#define TASK_WAKING 256
#define TASK_PARKED 512
-#define TASK_STATE_MAX 1024
+#define TASK_NOLOAD 1024
+#define TASK_STATE_MAX 2048
-#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWP"
+#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
extern char ___assert_task_state[1 - 2*!!(
sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
@@ -225,6 +231,8 @@ extern char ___assert_task_state[1 - 2*!!(
#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
+#define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
+
/* Convenience macros for the sake of wake_up */
#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
@@ -240,7 +248,8 @@ extern char ___assert_task_state[1 - 2*!!(
((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
#define task_contributes_to_load(task) \
((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
- (task->flags & PF_FROZEN) == 0)
+ (task->flags & PF_FROZEN) == 0 && \
+ (task->state & TASK_NOLOAD) == 0)
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
@@ -252,7 +261,7 @@ extern char ___assert_task_state[1 - 2*!!(
#define set_task_state(tsk, state_value) \
do { \
(tsk)->task_state_change = _THIS_IP_; \
- set_mb((tsk)->state, (state_value)); \
+ smp_store_mb((tsk)->state, (state_value)); \
} while (0)
/*
@@ -274,7 +283,7 @@ extern char ___assert_task_state[1 - 2*!!(
#define set_current_state(state_value) \
do { \
current->task_state_change = _THIS_IP_; \
- set_mb(current->state, (state_value)); \
+ smp_store_mb(current->state, (state_value)); \
} while (0)
#else
@@ -282,7 +291,7 @@ extern char ___assert_task_state[1 - 2*!!(
#define __set_task_state(tsk, state_value) \
do { (tsk)->state = (state_value); } while (0)
#define set_task_state(tsk, state_value) \
- set_mb((tsk)->state, (state_value))
+ smp_store_mb((tsk)->state, (state_value))
/*
* set_current_state() includes a barrier so that the write of current->state
@@ -298,7 +307,7 @@ extern char ___assert_task_state[1 - 2*!!(
#define __set_current_state(state_value) \
do { current->state = (state_value); } while (0)
#define set_current_state(state_value) \
- set_mb(current->state, (state_value))
+ smp_store_mb(current->state, (state_value))
#endif
@@ -330,17 +339,15 @@ extern void init_idle_bootup_task(struct task_struct *idle);
extern cpumask_var_t cpu_isolated_map;
+extern int runqueue_is_locked(int cpu);
+
#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
extern void nohz_balance_enter_idle(int cpu);
extern void set_cpu_sd_state_idle(void);
-extern int get_nohz_timer_target(int pinned);
+extern int get_nohz_timer_target(void);
#else
static inline void nohz_balance_enter_idle(int cpu) { }
static inline void set_cpu_sd_state_idle(void) { }
-static inline int get_nohz_timer_target(int pinned)
-{
- return smp_processor_id();
-}
#endif
/*
@@ -565,6 +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
@@ -582,18 +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>
@@ -732,18 +754,6 @@ struct signal_struct {
unsigned audit_tty_log_passwd;
struct tty_audit_buf *tty_audit_buf;
#endif
-#ifdef CONFIG_CGROUPS
- /*
- * group_rwsem prevents new tasks from entering the threadgroup and
- * member tasks from exiting,a more specifically, setting of
- * PF_EXITING. fork and exit paths are protected with this rwsem
- * using threadgroup_change_begin/end(). Users which require
- * threadgroup to remain stable should use threadgroup_[un]lock()
- * which also takes care of exec path. Currently, cgroup is the
- * only user.
- */
- struct rw_semaphore group_rwsem;
-#endif
oom_flags_t oom_flags;
short oom_score_adj; /* OOM kill score adjustment */
@@ -826,7 +836,7 @@ extern struct user_struct root_user;
struct backing_dev_info;
struct reclaim_state;
-#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+#ifdef CONFIG_SCHED_INFO
struct sched_info {
/* cumulative counters */
unsigned long pcount; /* # of times run on this cpu */
@@ -836,7 +846,7 @@ struct sched_info {
unsigned long long last_arrival,/* when we last ran on a cpu */
last_queued; /* when we were last queued to run */
};
-#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
+#endif /* CONFIG_SCHED_INFO */
#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info {
@@ -898,6 +908,50 @@ 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
@@ -1294,11 +1348,9 @@ struct task_struct {
unsigned int flags; /* per process flags, defined below */
unsigned int ptrace;
-#if defined(CONFIG_SMP) || defined(CONFIG_SCHED_BFS)
+#ifdef CONFIG_SMP
struct llist_node wake_entry;
int on_cpu;
-#endif
-#ifdef CONFIG_SMP
struct task_struct *last_wakee;
unsigned long wakee_flips;
unsigned long wakee_flip_decay_ts;
@@ -1306,29 +1358,12 @@ struct task_struct {
int wake_cpu;
#endif
int on_rq;
+
int prio, static_prio, normal_prio;
unsigned int rt_priority;
-#ifdef CONFIG_SCHED_BFS
- int time_slice;
- u64 deadline;
- struct list_head run_list;
- u64 last_ran;
- u64 sched_time; /* sched_clock time spent running */
-#ifdef CONFIG_SMT_NICE
- int smt_bias; /* Policy/nice level bias across smt siblings */
-#endif
-#ifdef CONFIG_SMP
- bool sticky; /* Soft affined flag */
-#endif
-#ifdef CONFIG_HOTPLUG_CPU
- bool zerobound; /* Bound to CPU0 for hotplug */
-#endif
- unsigned long rt_timeout;
-#else /* CONFIG_SCHED_BFS */
const struct sched_class *sched_class;
struct sched_entity se;
struct sched_rt_entity rt;
-#endif
#ifdef CONFIG_CGROUP_SCHED
struct task_group *sched_task_group;
#endif
@@ -1351,8 +1386,6 @@ 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
@@ -1362,7 +1395,7 @@ struct task_struct {
int rcu_tasks_idle_cpu;
#endif /* #ifdef CONFIG_TASKS_RCU */
-#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+#ifdef CONFIG_SCHED_INFO
struct sched_info sched_info;
#endif
@@ -1373,9 +1406,6 @@ struct task_struct {
#endif
struct mm_struct *mm, *active_mm;
-#ifdef CONFIG_COMPAT_BRK
- unsigned brk_randomized:1;
-#endif
/* per-thread vma caching */
u32 vmacache_seqnum;
struct vm_area_struct *vmacache[VMACACHE_SIZE];
@@ -1386,7 +1416,7 @@ 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;
@@ -1398,10 +1428,14 @@ struct task_struct {
/* Revert to default priority/policy when forking */
unsigned sched_reset_on_fork:1;
unsigned sched_contributes_to_load:1;
+ unsigned sched_migrated:1;
#ifdef CONFIG_MEMCG_KMEM
unsigned memcg_kmem_skip_account:1;
#endif
+#ifdef CONFIG_COMPAT_BRK
+ unsigned brk_randomized:1;
+#endif
unsigned long atomic_flags; /* Flags needing atomic access. */
@@ -1446,9 +1480,6 @@ struct task_struct {
int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
cputime_t utime, stime, utimescaled, stimescaled;
-#ifdef CONFIG_SCHED_BFS
- unsigned long utime_pc, stime_pc;
-#endif
cputime_t gtime;
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
struct cputime prev_cputime;
@@ -1481,7 +1512,7 @@ struct task_struct {
it with task_lock())
- initialized normally by setup_new_exec */
/* file system info */
- int link_count, total_link_count;
+ struct nameidata *nameidata;
#ifdef CONFIG_SYSVIPC
/* ipc stuff */
struct sysv_sem sysvsem;
@@ -1491,8 +1522,6 @@ struct task_struct {
/* hung task detection */
unsigned long last_switch_count;
#endif
-/* CPU-specific state of this task */
- struct thread_struct thread;
/* filesystem information */
struct fs_struct *fs;
/* open file information */
@@ -1531,6 +1560,8 @@ 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;
@@ -1744,64 +1775,22 @@ struct task_struct {
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
unsigned long task_state_change;
#endif
+ int pagefault_disabled;
+/* CPU-specific state of this task */
+ struct thread_struct thread;
+/*
+ * WARNING: on x86, 'thread_struct' contains a variable-sized
+ * structure. It *MUST* be at the end of 'task_struct'.
+ *
+ * Do not put anything below here!
+ */
};
-#ifdef CONFIG_SCHED_BFS
-bool grunqueue_is_locked(void);
-void grq_unlock_wait(void);
-void cpu_scaling(int cpu);
-void cpu_nonscaling(int cpu);
-#define tsk_seruntime(t) ((t)->sched_time)
-#define tsk_rttimeout(t) ((t)->rt_timeout)
-
-static inline void tsk_cpus_current(struct task_struct *p)
-{
-}
-
-static inline int runqueue_is_locked(int cpu)
-{
- return grunqueue_is_locked();
-}
-
-void print_scheduler_version(void);
-
-static inline bool iso_task(struct task_struct *p)
-{
- return (p->policy == SCHED_ISO);
-}
-#else /* CFS */
-extern int runqueue_is_locked(int cpu);
-static inline void cpu_scaling(int cpu)
-{
-}
-
-static inline void cpu_nonscaling(int cpu)
-{
-}
-#define tsk_seruntime(t) ((t)->se.sum_exec_runtime)
-#define tsk_rttimeout(t) ((t)->rt.timeout)
-
-static inline void tsk_cpus_current(struct task_struct *p)
-{
- p->nr_cpus_allowed = current->nr_cpus_allowed;
-}
-
-static inline void print_scheduler_version(void)
-{
- printk(KERN_INFO"CFS CPU scheduler.\n");
-}
-
-static inline bool iso_task(struct task_struct *p)
-{
- return false;
-}
-
-/* Anyone feel like implementing this? */
-static inline bool above_background_load(void)
-{
- return false;
-}
-#endif /* CONFIG_SCHED_BFS */
+#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
+extern int arch_task_struct_size __read_mostly;
+#else
+# define arch_task_struct_size (sizeof(struct task_struct))
+#endif
/* Future-safe accessor for struct task_struct's cpus_allowed. */
#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
@@ -2154,22 +2143,22 @@ 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)
{
@@ -2297,7 +2286,7 @@ extern unsigned long long
task_sched_runtime(struct task_struct *task);
/* sched_exec is called by processes performing an exec */
-#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_BFS)
+#ifdef CONFIG_SMP
extern void sched_exec(void);
#else
#define sched_exec() {}
@@ -2442,7 +2431,6 @@ extern void sched_dead(struct task_struct *p);
extern void proc_caches_init(void);
extern void flush_signals(struct task_struct *);
-extern void __flush_signals(struct task_struct *);
extern void ignore_signals(struct task_struct *);
extern void flush_signal_handlers(struct task_struct *, int force_default);
extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
@@ -2566,8 +2554,22 @@ extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
/* Remove the current tasks stale references to the old mm_struct */
extern void mm_release(struct task_struct *, struct mm_struct *);
+#ifdef CONFIG_HAVE_COPY_THREAD_TLS
+extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
+ struct task_struct *, unsigned long);
+#else
extern int copy_thread(unsigned long, unsigned long, unsigned long,
struct task_struct *);
+
+/* Architectures that haven't opted into copy_thread_tls get the tls argument
+ * via pt_regs, so ignore the tls argument passed via C. */
+static inline int copy_thread_tls(
+ unsigned long clone_flags, unsigned long sp, unsigned long arg,
+ struct task_struct *p, unsigned long tls)
+{
+ return copy_thread(clone_flags, sp, arg, p);
+}
+#endif
extern void flush_thread(void);
extern void exit_thread(void);
@@ -2586,6 +2588,7 @@ extern int do_execveat(int, struct filename *,
const char __user * const __user *,
const char __user * const __user *,
int);
+extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
struct task_struct *fork_idle(int);
extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
@@ -2609,6 +2612,9 @@ static inline unsigned long wait_task_inactive(struct task_struct *p,
}
#endif
+#define tasklist_empty() \
+ list_empty(&init_task.tasks)
+
#define next_task(p) \
list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
@@ -2717,53 +2723,33 @@ static inline void unlock_task_sighand(struct task_struct *tsk,
spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
}
-#ifdef CONFIG_CGROUPS
-static inline void threadgroup_change_begin(struct task_struct *tsk)
-{
- down_read(&tsk->signal->group_rwsem);
-}
-static inline void 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 paths 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.
+ * threadgroup_change_begin - mark the beginning of changes to a threadgroup
+ * @tsk: task causing the changes
*
- * de_thread() does threadgroup_change_{begin|end}() when a non-leader
- * sub-thread becomes a new leader.
+ * All operations which modify a threadgroup - a new thread joining the
+ * group, death of a member thread (the assertion of PF_EXITING) and
+ * exec(2) dethreading the process and replacing the leader - are wrapped
+ * by threadgroup_change_{begin|end}(). This is to provide a place which
+ * subsystems needing threadgroup stability can hook into for
+ * synchronization.
*/
-static inline void threadgroup_lock(struct task_struct *tsk)
+static inline void threadgroup_change_begin(struct task_struct *tsk)
{
- down_write(&tsk->signal->group_rwsem);
+ might_sleep();
+ cgroup_threadgroup_change_begin(tsk);
}
/**
- * threadgroup_unlock - unlock threadgroup
- * @tsk: member task of the threadgroup to unlock
+ * threadgroup_change_end - mark the end of changes to a threadgroup
+ * @tsk: task causing the changes
*
- * Reverse threadgroup_lock().
+ * See threadgroup_change_begin().
*/
-static inline void threadgroup_unlock(struct task_struct *tsk)
+static inline void threadgroup_change_end(struct task_struct *tsk)
{
- up_write(&tsk->signal->group_rwsem);
+ cgroup_threadgroup_change_end(tsk);
}
-#else
-static inline void threadgroup_change_begin(struct task_struct *tsk) {}
-static inline void threadgroup_change_end(struct task_struct *tsk) {}
-static inline void threadgroup_lock(struct task_struct *tsk) {}
-static inline void threadgroup_unlock(struct task_struct *tsk) {}
-#endif
#ifndef __HAVE_THREAD_FUNCTIONS
@@ -3039,11 +3025,6 @@ 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.
@@ -3088,7 +3069,7 @@ static inline unsigned int task_cpu(const struct task_struct *p)
return 0;
}
-static inline void set_task_cpu(struct task_struct *p, int cpu)
+static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
{
}
@@ -3157,13 +3138,13 @@ 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)