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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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![Linus Torvalds](/assets/img/avatar_default.png)
Pull core signal handling updates from Eric Biederman: "It was observed that a periodic timer in combination with a sufficiently expensive fork could prevent fork from every completing. This contains the changes to remove the need for that restart. This set of changes is split into several parts: - The first part makes PIDTYPE_TGID a proper pid type instead something only for very special cases. The part starts using PIDTYPE_TGID enough so that in __send_signal where signals are actually delivered we know if the signal is being sent to a a group of processes or just a single process. - With that prep work out of the way the logic in fork is modified so that fork logically makes signals received while it is running appear to be received after the fork completes" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits) signal: Don't send signals to tasks that don't exist signal: Don't restart fork when signals come in. fork: Have new threads join on-going signal group stops fork: Skip setting TIF_SIGPENDING in ptrace_init_task signal: Add calculate_sigpending() fork: Unconditionally exit if a fatal signal is pending fork: Move and describe why the code examines PIDNS_ADDING signal: Push pid type down into complete_signal. signal: Push pid type down into __send_signal signal: Push pid type down into send_signal signal: Pass pid type into do_send_sig_info signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task signal: Pass pid type into group_send_sig_info signal: Pass pid and pid type into send_sigqueue posix-timers: Noralize good_sigevent signal: Use PIDTYPE_TGID to clearly store where file signals will be sent pid: Implement PIDTYPE_TGID pids: Move the pgrp and session pid pointers from task_struct to signal_struct kvm: Don't open code task_pid in kvm_vcpu_ioctl pids: Compute task_tgid using signal->leader_pid ...
1445 lines
38 KiB
C
1445 lines
38 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Implement CPU time clocks for the POSIX clock interface.
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*/
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#include <linux/sched/signal.h>
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#include <linux/sched/cputime.h>
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#include <linux/posix-timers.h>
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#include <linux/errno.h>
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#include <linux/math64.h>
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#include <linux/uaccess.h>
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#include <linux/kernel_stat.h>
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#include <trace/events/timer.h>
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#include <linux/tick.h>
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#include <linux/workqueue.h>
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#include <linux/compat.h>
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#include <linux/sched/deadline.h>
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#include "posix-timers.h"
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static void posix_cpu_timer_rearm(struct k_itimer *timer);
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/*
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* Called after updating RLIMIT_CPU to run cpu timer and update
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* tsk->signal->cputime_expires expiration cache if necessary. Needs
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* siglock protection since other code may update expiration cache as
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* well.
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*/
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void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new)
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{
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u64 nsecs = rlim_new * NSEC_PER_SEC;
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spin_lock_irq(&task->sighand->siglock);
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set_process_cpu_timer(task, CPUCLOCK_PROF, &nsecs, NULL);
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spin_unlock_irq(&task->sighand->siglock);
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}
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static int check_clock(const clockid_t which_clock)
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{
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int error = 0;
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struct task_struct *p;
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const pid_t pid = CPUCLOCK_PID(which_clock);
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if (CPUCLOCK_WHICH(which_clock) >= CPUCLOCK_MAX)
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return -EINVAL;
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if (pid == 0)
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return 0;
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rcu_read_lock();
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p = find_task_by_vpid(pid);
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if (!p || !(CPUCLOCK_PERTHREAD(which_clock) ?
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same_thread_group(p, current) : has_group_leader_pid(p))) {
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error = -EINVAL;
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}
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rcu_read_unlock();
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return error;
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}
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/*
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* Update expiry time from increment, and increase overrun count,
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* given the current clock sample.
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*/
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static void bump_cpu_timer(struct k_itimer *timer, u64 now)
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{
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int i;
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u64 delta, incr;
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if (timer->it.cpu.incr == 0)
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return;
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if (now < timer->it.cpu.expires)
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return;
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incr = timer->it.cpu.incr;
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delta = now + incr - timer->it.cpu.expires;
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/* Don't use (incr*2 < delta), incr*2 might overflow. */
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for (i = 0; incr < delta - incr; i++)
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incr = incr << 1;
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for (; i >= 0; incr >>= 1, i--) {
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if (delta < incr)
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continue;
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timer->it.cpu.expires += incr;
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timer->it_overrun += 1LL << i;
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delta -= incr;
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}
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}
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/**
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* task_cputime_zero - Check a task_cputime struct for all zero fields.
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*
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* @cputime: The struct to compare.
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*
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* Checks @cputime to see if all fields are zero. Returns true if all fields
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* are zero, false if any field is nonzero.
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*/
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static inline int task_cputime_zero(const struct task_cputime *cputime)
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{
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if (!cputime->utime && !cputime->stime && !cputime->sum_exec_runtime)
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return 1;
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return 0;
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}
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static inline u64 prof_ticks(struct task_struct *p)
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{
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u64 utime, stime;
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task_cputime(p, &utime, &stime);
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return utime + stime;
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}
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static inline u64 virt_ticks(struct task_struct *p)
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{
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u64 utime, stime;
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task_cputime(p, &utime, &stime);
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return utime;
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}
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static int
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posix_cpu_clock_getres(const clockid_t which_clock, struct timespec64 *tp)
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{
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int error = check_clock(which_clock);
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if (!error) {
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tp->tv_sec = 0;
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tp->tv_nsec = ((NSEC_PER_SEC + HZ - 1) / HZ);
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if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
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/*
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* If sched_clock is using a cycle counter, we
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* don't have any idea of its true resolution
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* exported, but it is much more than 1s/HZ.
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*/
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tp->tv_nsec = 1;
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}
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}
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return error;
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}
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static int
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posix_cpu_clock_set(const clockid_t which_clock, const struct timespec64 *tp)
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{
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/*
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* You can never reset a CPU clock, but we check for other errors
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* in the call before failing with EPERM.
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*/
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int error = check_clock(which_clock);
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if (error == 0) {
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error = -EPERM;
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}
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return error;
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}
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/*
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* Sample a per-thread clock for the given task.
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*/
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static int cpu_clock_sample(const clockid_t which_clock,
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struct task_struct *p, u64 *sample)
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{
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switch (CPUCLOCK_WHICH(which_clock)) {
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default:
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return -EINVAL;
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case CPUCLOCK_PROF:
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*sample = prof_ticks(p);
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break;
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case CPUCLOCK_VIRT:
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*sample = virt_ticks(p);
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break;
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case CPUCLOCK_SCHED:
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*sample = task_sched_runtime(p);
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break;
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}
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return 0;
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}
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/*
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* Set cputime to sum_cputime if sum_cputime > cputime. Use cmpxchg
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* to avoid race conditions with concurrent updates to cputime.
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*/
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static inline void __update_gt_cputime(atomic64_t *cputime, u64 sum_cputime)
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{
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u64 curr_cputime;
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retry:
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curr_cputime = atomic64_read(cputime);
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if (sum_cputime > curr_cputime) {
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if (atomic64_cmpxchg(cputime, curr_cputime, sum_cputime) != curr_cputime)
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goto retry;
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}
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}
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static void update_gt_cputime(struct task_cputime_atomic *cputime_atomic, struct task_cputime *sum)
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{
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__update_gt_cputime(&cputime_atomic->utime, sum->utime);
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__update_gt_cputime(&cputime_atomic->stime, sum->stime);
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__update_gt_cputime(&cputime_atomic->sum_exec_runtime, sum->sum_exec_runtime);
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}
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/* Sample task_cputime_atomic values in "atomic_timers", store results in "times". */
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static inline void sample_cputime_atomic(struct task_cputime *times,
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struct task_cputime_atomic *atomic_times)
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{
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times->utime = atomic64_read(&atomic_times->utime);
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times->stime = atomic64_read(&atomic_times->stime);
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times->sum_exec_runtime = atomic64_read(&atomic_times->sum_exec_runtime);
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}
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void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times)
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{
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struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
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struct task_cputime sum;
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/* Check if cputimer isn't running. This is accessed without locking. */
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if (!READ_ONCE(cputimer->running)) {
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/*
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* The POSIX timer interface allows for absolute time expiry
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* values through the TIMER_ABSTIME flag, therefore we have
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* to synchronize the timer to the clock every time we start it.
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*/
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thread_group_cputime(tsk, &sum);
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update_gt_cputime(&cputimer->cputime_atomic, &sum);
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/*
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* We're setting cputimer->running without a lock. Ensure
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* this only gets written to in one operation. We set
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* running after update_gt_cputime() as a small optimization,
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* but barriers are not required because update_gt_cputime()
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* can handle concurrent updates.
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*/
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WRITE_ONCE(cputimer->running, true);
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}
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sample_cputime_atomic(times, &cputimer->cputime_atomic);
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}
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/*
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* Sample a process (thread group) clock for the given group_leader task.
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* Must be called with task sighand lock held for safe while_each_thread()
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* traversal.
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*/
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static int cpu_clock_sample_group(const clockid_t which_clock,
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struct task_struct *p,
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u64 *sample)
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{
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struct task_cputime cputime;
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switch (CPUCLOCK_WHICH(which_clock)) {
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default:
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return -EINVAL;
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case CPUCLOCK_PROF:
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thread_group_cputime(p, &cputime);
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*sample = cputime.utime + cputime.stime;
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break;
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case CPUCLOCK_VIRT:
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thread_group_cputime(p, &cputime);
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*sample = cputime.utime;
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break;
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case CPUCLOCK_SCHED:
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thread_group_cputime(p, &cputime);
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*sample = cputime.sum_exec_runtime;
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break;
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}
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return 0;
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}
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static int posix_cpu_clock_get_task(struct task_struct *tsk,
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const clockid_t which_clock,
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struct timespec64 *tp)
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{
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int err = -EINVAL;
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u64 rtn;
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if (CPUCLOCK_PERTHREAD(which_clock)) {
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if (same_thread_group(tsk, current))
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err = cpu_clock_sample(which_clock, tsk, &rtn);
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} else {
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if (tsk == current || thread_group_leader(tsk))
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err = cpu_clock_sample_group(which_clock, tsk, &rtn);
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}
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if (!err)
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*tp = ns_to_timespec64(rtn);
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return err;
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}
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static int posix_cpu_clock_get(const clockid_t which_clock, struct timespec64 *tp)
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{
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const pid_t pid = CPUCLOCK_PID(which_clock);
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int err = -EINVAL;
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if (pid == 0) {
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/*
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* Special case constant value for our own clocks.
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* We don't have to do any lookup to find ourselves.
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*/
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err = posix_cpu_clock_get_task(current, which_clock, tp);
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} else {
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/*
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* Find the given PID, and validate that the caller
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* should be able to see it.
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*/
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struct task_struct *p;
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rcu_read_lock();
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p = find_task_by_vpid(pid);
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if (p)
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err = posix_cpu_clock_get_task(p, which_clock, tp);
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rcu_read_unlock();
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}
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return err;
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}
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/*
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* Validate the clockid_t for a new CPU-clock timer, and initialize the timer.
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* This is called from sys_timer_create() and do_cpu_nanosleep() with the
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* new timer already all-zeros initialized.
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*/
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static int posix_cpu_timer_create(struct k_itimer *new_timer)
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{
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int ret = 0;
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const pid_t pid = CPUCLOCK_PID(new_timer->it_clock);
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struct task_struct *p;
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if (CPUCLOCK_WHICH(new_timer->it_clock) >= CPUCLOCK_MAX)
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return -EINVAL;
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new_timer->kclock = &clock_posix_cpu;
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INIT_LIST_HEAD(&new_timer->it.cpu.entry);
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rcu_read_lock();
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if (CPUCLOCK_PERTHREAD(new_timer->it_clock)) {
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if (pid == 0) {
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p = current;
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} else {
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p = find_task_by_vpid(pid);
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if (p && !same_thread_group(p, current))
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p = NULL;
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}
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} else {
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if (pid == 0) {
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p = current->group_leader;
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} else {
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p = find_task_by_vpid(pid);
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if (p && !has_group_leader_pid(p))
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p = NULL;
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}
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}
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new_timer->it.cpu.task = p;
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if (p) {
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get_task_struct(p);
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} else {
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ret = -EINVAL;
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}
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rcu_read_unlock();
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return ret;
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}
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/*
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* Clean up a CPU-clock timer that is about to be destroyed.
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* This is called from timer deletion with the timer already locked.
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* If we return TIMER_RETRY, it's necessary to release the timer's lock
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* and try again. (This happens when the timer is in the middle of firing.)
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*/
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static int posix_cpu_timer_del(struct k_itimer *timer)
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{
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int ret = 0;
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unsigned long flags;
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struct sighand_struct *sighand;
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struct task_struct *p = timer->it.cpu.task;
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WARN_ON_ONCE(p == NULL);
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/*
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* Protect against sighand release/switch in exit/exec and process/
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* thread timer list entry concurrent read/writes.
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*/
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sighand = lock_task_sighand(p, &flags);
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if (unlikely(sighand == NULL)) {
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/*
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* We raced with the reaping of the task.
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* The deletion should have cleared us off the list.
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*/
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WARN_ON_ONCE(!list_empty(&timer->it.cpu.entry));
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} else {
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if (timer->it.cpu.firing)
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ret = TIMER_RETRY;
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else
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list_del(&timer->it.cpu.entry);
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unlock_task_sighand(p, &flags);
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}
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if (!ret)
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put_task_struct(p);
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return ret;
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}
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static void cleanup_timers_list(struct list_head *head)
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{
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struct cpu_timer_list *timer, *next;
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list_for_each_entry_safe(timer, next, head, entry)
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list_del_init(&timer->entry);
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}
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/*
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* Clean out CPU timers still ticking when a thread exited. The task
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* pointer is cleared, and the expiry time is replaced with the residual
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* time for later timer_gettime calls to return.
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* This must be called with the siglock held.
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*/
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static void cleanup_timers(struct list_head *head)
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{
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cleanup_timers_list(head);
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cleanup_timers_list(++head);
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cleanup_timers_list(++head);
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}
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/*
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* These are both called with the siglock held, when the current thread
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* is being reaped. When the final (leader) thread in the group is reaped,
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* posix_cpu_timers_exit_group will be called after posix_cpu_timers_exit.
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*/
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void posix_cpu_timers_exit(struct task_struct *tsk)
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{
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cleanup_timers(tsk->cpu_timers);
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}
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void posix_cpu_timers_exit_group(struct task_struct *tsk)
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{
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cleanup_timers(tsk->signal->cpu_timers);
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}
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|
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static inline int expires_gt(u64 expires, u64 new_exp)
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{
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return expires == 0 || expires > new_exp;
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}
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|
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/*
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* Insert the timer on the appropriate list before any timers that
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* expire later. This must be called with the sighand lock held.
|
|
*/
|
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static void arm_timer(struct k_itimer *timer)
|
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{
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struct task_struct *p = timer->it.cpu.task;
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struct list_head *head, *listpos;
|
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struct task_cputime *cputime_expires;
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struct cpu_timer_list *const nt = &timer->it.cpu;
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struct cpu_timer_list *next;
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|
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if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
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head = p->cpu_timers;
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cputime_expires = &p->cputime_expires;
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} else {
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head = p->signal->cpu_timers;
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cputime_expires = &p->signal->cputime_expires;
|
|
}
|
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head += CPUCLOCK_WHICH(timer->it_clock);
|
|
|
|
listpos = head;
|
|
list_for_each_entry(next, head, entry) {
|
|
if (nt->expires < next->expires)
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|
break;
|
|
listpos = &next->entry;
|
|
}
|
|
list_add(&nt->entry, listpos);
|
|
|
|
if (listpos == head) {
|
|
u64 exp = nt->expires;
|
|
|
|
/*
|
|
* We are the new earliest-expiring POSIX 1.b timer, hence
|
|
* need to update expiration cache. Take into account that
|
|
* for process timers we share expiration cache with itimers
|
|
* and RLIMIT_CPU and for thread timers with RLIMIT_RTTIME.
|
|
*/
|
|
|
|
switch (CPUCLOCK_WHICH(timer->it_clock)) {
|
|
case CPUCLOCK_PROF:
|
|
if (expires_gt(cputime_expires->prof_exp, exp))
|
|
cputime_expires->prof_exp = exp;
|
|
break;
|
|
case CPUCLOCK_VIRT:
|
|
if (expires_gt(cputime_expires->virt_exp, exp))
|
|
cputime_expires->virt_exp = exp;
|
|
break;
|
|
case CPUCLOCK_SCHED:
|
|
if (expires_gt(cputime_expires->sched_exp, exp))
|
|
cputime_expires->sched_exp = exp;
|
|
break;
|
|
}
|
|
if (CPUCLOCK_PERTHREAD(timer->it_clock))
|
|
tick_dep_set_task(p, TICK_DEP_BIT_POSIX_TIMER);
|
|
else
|
|
tick_dep_set_signal(p->signal, TICK_DEP_BIT_POSIX_TIMER);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* The timer is locked, fire it and arrange for its reload.
|
|
*/
|
|
static void cpu_timer_fire(struct k_itimer *timer)
|
|
{
|
|
if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
|
|
/*
|
|
* User don't want any signal.
|
|
*/
|
|
timer->it.cpu.expires = 0;
|
|
} else if (unlikely(timer->sigq == NULL)) {
|
|
/*
|
|
* This a special case for clock_nanosleep,
|
|
* not a normal timer from sys_timer_create.
|
|
*/
|
|
wake_up_process(timer->it_process);
|
|
timer->it.cpu.expires = 0;
|
|
} else if (timer->it.cpu.incr == 0) {
|
|
/*
|
|
* One-shot timer. Clear it as soon as it's fired.
|
|
*/
|
|
posix_timer_event(timer, 0);
|
|
timer->it.cpu.expires = 0;
|
|
} else if (posix_timer_event(timer, ++timer->it_requeue_pending)) {
|
|
/*
|
|
* The signal did not get queued because the signal
|
|
* was ignored, so we won't get any callback to
|
|
* reload the timer. But we need to keep it
|
|
* ticking in case the signal is deliverable next time.
|
|
*/
|
|
posix_cpu_timer_rearm(timer);
|
|
++timer->it_requeue_pending;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Sample a process (thread group) timer for the given group_leader task.
|
|
* Must be called with task sighand lock held for safe while_each_thread()
|
|
* traversal.
|
|
*/
|
|
static int cpu_timer_sample_group(const clockid_t which_clock,
|
|
struct task_struct *p, u64 *sample)
|
|
{
|
|
struct task_cputime cputime;
|
|
|
|
thread_group_cputimer(p, &cputime);
|
|
switch (CPUCLOCK_WHICH(which_clock)) {
|
|
default:
|
|
return -EINVAL;
|
|
case CPUCLOCK_PROF:
|
|
*sample = cputime.utime + cputime.stime;
|
|
break;
|
|
case CPUCLOCK_VIRT:
|
|
*sample = cputime.utime;
|
|
break;
|
|
case CPUCLOCK_SCHED:
|
|
*sample = cputime.sum_exec_runtime;
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Guts of sys_timer_settime for CPU timers.
|
|
* This is called with the timer locked and interrupts disabled.
|
|
* If we return TIMER_RETRY, it's necessary to release the timer's lock
|
|
* and try again. (This happens when the timer is in the middle of firing.)
|
|
*/
|
|
static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags,
|
|
struct itimerspec64 *new, struct itimerspec64 *old)
|
|
{
|
|
unsigned long flags;
|
|
struct sighand_struct *sighand;
|
|
struct task_struct *p = timer->it.cpu.task;
|
|
u64 old_expires, new_expires, old_incr, val;
|
|
int ret;
|
|
|
|
WARN_ON_ONCE(p == NULL);
|
|
|
|
/*
|
|
* Use the to_ktime conversion because that clamps the maximum
|
|
* value to KTIME_MAX and avoid multiplication overflows.
|
|
*/
|
|
new_expires = ktime_to_ns(timespec64_to_ktime(new->it_value));
|
|
|
|
/*
|
|
* Protect against sighand release/switch in exit/exec and p->cpu_timers
|
|
* and p->signal->cpu_timers read/write in arm_timer()
|
|
*/
|
|
sighand = lock_task_sighand(p, &flags);
|
|
/*
|
|
* If p has just been reaped, we can no
|
|
* longer get any information about it at all.
|
|
*/
|
|
if (unlikely(sighand == NULL)) {
|
|
return -ESRCH;
|
|
}
|
|
|
|
/*
|
|
* Disarm any old timer after extracting its expiry time.
|
|
*/
|
|
|
|
ret = 0;
|
|
old_incr = timer->it.cpu.incr;
|
|
old_expires = timer->it.cpu.expires;
|
|
if (unlikely(timer->it.cpu.firing)) {
|
|
timer->it.cpu.firing = -1;
|
|
ret = TIMER_RETRY;
|
|
} else
|
|
list_del_init(&timer->it.cpu.entry);
|
|
|
|
/*
|
|
* We need to sample the current value to convert the new
|
|
* value from to relative and absolute, and to convert the
|
|
* old value from absolute to relative. To set a process
|
|
* timer, we need a sample to balance the thread expiry
|
|
* times (in arm_timer). With an absolute time, we must
|
|
* check if it's already passed. In short, we need a sample.
|
|
*/
|
|
if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
|
|
cpu_clock_sample(timer->it_clock, p, &val);
|
|
} else {
|
|
cpu_timer_sample_group(timer->it_clock, p, &val);
|
|
}
|
|
|
|
if (old) {
|
|
if (old_expires == 0) {
|
|
old->it_value.tv_sec = 0;
|
|
old->it_value.tv_nsec = 0;
|
|
} else {
|
|
/*
|
|
* Update the timer in case it has
|
|
* overrun already. If it has,
|
|
* we'll report it as having overrun
|
|
* and with the next reloaded timer
|
|
* already ticking, though we are
|
|
* swallowing that pending
|
|
* notification here to install the
|
|
* new setting.
|
|
*/
|
|
bump_cpu_timer(timer, val);
|
|
if (val < timer->it.cpu.expires) {
|
|
old_expires = timer->it.cpu.expires - val;
|
|
old->it_value = ns_to_timespec64(old_expires);
|
|
} else {
|
|
old->it_value.tv_nsec = 1;
|
|
old->it_value.tv_sec = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (unlikely(ret)) {
|
|
/*
|
|
* We are colliding with the timer actually firing.
|
|
* Punt after filling in the timer's old value, and
|
|
* disable this firing since we are already reporting
|
|
* it as an overrun (thanks to bump_cpu_timer above).
|
|
*/
|
|
unlock_task_sighand(p, &flags);
|
|
goto out;
|
|
}
|
|
|
|
if (new_expires != 0 && !(timer_flags & TIMER_ABSTIME)) {
|
|
new_expires += val;
|
|
}
|
|
|
|
/*
|
|
* Install the new expiry time (or zero).
|
|
* For a timer with no notification action, we don't actually
|
|
* arm the timer (we'll just fake it for timer_gettime).
|
|
*/
|
|
timer->it.cpu.expires = new_expires;
|
|
if (new_expires != 0 && val < new_expires) {
|
|
arm_timer(timer);
|
|
}
|
|
|
|
unlock_task_sighand(p, &flags);
|
|
/*
|
|
* Install the new reload setting, and
|
|
* set up the signal and overrun bookkeeping.
|
|
*/
|
|
timer->it.cpu.incr = timespec64_to_ns(&new->it_interval);
|
|
|
|
/*
|
|
* This acts as a modification timestamp for the timer,
|
|
* so any automatic reload attempt will punt on seeing
|
|
* that we have reset the timer manually.
|
|
*/
|
|
timer->it_requeue_pending = (timer->it_requeue_pending + 2) &
|
|
~REQUEUE_PENDING;
|
|
timer->it_overrun_last = 0;
|
|
timer->it_overrun = -1;
|
|
|
|
if (new_expires != 0 && !(val < new_expires)) {
|
|
/*
|
|
* The designated time already passed, so we notify
|
|
* immediately, even if the thread never runs to
|
|
* accumulate more time on this clock.
|
|
*/
|
|
cpu_timer_fire(timer);
|
|
}
|
|
|
|
ret = 0;
|
|
out:
|
|
if (old)
|
|
old->it_interval = ns_to_timespec64(old_incr);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec64 *itp)
|
|
{
|
|
u64 now;
|
|
struct task_struct *p = timer->it.cpu.task;
|
|
|
|
WARN_ON_ONCE(p == NULL);
|
|
|
|
/*
|
|
* Easy part: convert the reload time.
|
|
*/
|
|
itp->it_interval = ns_to_timespec64(timer->it.cpu.incr);
|
|
|
|
if (!timer->it.cpu.expires)
|
|
return;
|
|
|
|
/*
|
|
* Sample the clock to take the difference with the expiry time.
|
|
*/
|
|
if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
|
|
cpu_clock_sample(timer->it_clock, p, &now);
|
|
} else {
|
|
struct sighand_struct *sighand;
|
|
unsigned long flags;
|
|
|
|
/*
|
|
* Protect against sighand release/switch in exit/exec and
|
|
* also make timer sampling safe if it ends up calling
|
|
* thread_group_cputime().
|
|
*/
|
|
sighand = lock_task_sighand(p, &flags);
|
|
if (unlikely(sighand == NULL)) {
|
|
/*
|
|
* The process has been reaped.
|
|
* We can't even collect a sample any more.
|
|
* Call the timer disarmed, nothing else to do.
|
|
*/
|
|
timer->it.cpu.expires = 0;
|
|
return;
|
|
} else {
|
|
cpu_timer_sample_group(timer->it_clock, p, &now);
|
|
unlock_task_sighand(p, &flags);
|
|
}
|
|
}
|
|
|
|
if (now < timer->it.cpu.expires) {
|
|
itp->it_value = ns_to_timespec64(timer->it.cpu.expires - now);
|
|
} else {
|
|
/*
|
|
* The timer should have expired already, but the firing
|
|
* hasn't taken place yet. Say it's just about to expire.
|
|
*/
|
|
itp->it_value.tv_nsec = 1;
|
|
itp->it_value.tv_sec = 0;
|
|
}
|
|
}
|
|
|
|
static unsigned long long
|
|
check_timers_list(struct list_head *timers,
|
|
struct list_head *firing,
|
|
unsigned long long curr)
|
|
{
|
|
int maxfire = 20;
|
|
|
|
while (!list_empty(timers)) {
|
|
struct cpu_timer_list *t;
|
|
|
|
t = list_first_entry(timers, struct cpu_timer_list, entry);
|
|
|
|
if (!--maxfire || curr < t->expires)
|
|
return t->expires;
|
|
|
|
t->firing = 1;
|
|
list_move_tail(&t->entry, firing);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline void check_dl_overrun(struct task_struct *tsk)
|
|
{
|
|
if (tsk->dl.dl_overrun) {
|
|
tsk->dl.dl_overrun = 0;
|
|
__group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check for any per-thread CPU timers that have fired and move them off
|
|
* the tsk->cpu_timers[N] list onto the firing list. Here we update the
|
|
* tsk->it_*_expires values to reflect the remaining thread CPU timers.
|
|
*/
|
|
static void check_thread_timers(struct task_struct *tsk,
|
|
struct list_head *firing)
|
|
{
|
|
struct list_head *timers = tsk->cpu_timers;
|
|
struct task_cputime *tsk_expires = &tsk->cputime_expires;
|
|
u64 expires;
|
|
unsigned long soft;
|
|
|
|
if (dl_task(tsk))
|
|
check_dl_overrun(tsk);
|
|
|
|
/*
|
|
* If cputime_expires is zero, then there are no active
|
|
* per thread CPU timers.
|
|
*/
|
|
if (task_cputime_zero(&tsk->cputime_expires))
|
|
return;
|
|
|
|
expires = check_timers_list(timers, firing, prof_ticks(tsk));
|
|
tsk_expires->prof_exp = expires;
|
|
|
|
expires = check_timers_list(++timers, firing, virt_ticks(tsk));
|
|
tsk_expires->virt_exp = expires;
|
|
|
|
tsk_expires->sched_exp = check_timers_list(++timers, firing,
|
|
tsk->se.sum_exec_runtime);
|
|
|
|
/*
|
|
* Check for the special case thread timers.
|
|
*/
|
|
soft = task_rlimit(tsk, RLIMIT_RTTIME);
|
|
if (soft != RLIM_INFINITY) {
|
|
unsigned long hard = task_rlimit_max(tsk, RLIMIT_RTTIME);
|
|
|
|
if (hard != RLIM_INFINITY &&
|
|
tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
|
|
/*
|
|
* At the hard limit, we just die.
|
|
* No need to calculate anything else now.
|
|
*/
|
|
if (print_fatal_signals) {
|
|
pr_info("CPU Watchdog Timeout (hard): %s[%d]\n",
|
|
tsk->comm, task_pid_nr(tsk));
|
|
}
|
|
__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
|
|
return;
|
|
}
|
|
if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) {
|
|
/*
|
|
* At the soft limit, send a SIGXCPU every second.
|
|
*/
|
|
if (soft < hard) {
|
|
soft += USEC_PER_SEC;
|
|
tsk->signal->rlim[RLIMIT_RTTIME].rlim_cur =
|
|
soft;
|
|
}
|
|
if (print_fatal_signals) {
|
|
pr_info("RT Watchdog Timeout (soft): %s[%d]\n",
|
|
tsk->comm, task_pid_nr(tsk));
|
|
}
|
|
__group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
|
|
}
|
|
}
|
|
if (task_cputime_zero(tsk_expires))
|
|
tick_dep_clear_task(tsk, TICK_DEP_BIT_POSIX_TIMER);
|
|
}
|
|
|
|
static inline void stop_process_timers(struct signal_struct *sig)
|
|
{
|
|
struct thread_group_cputimer *cputimer = &sig->cputimer;
|
|
|
|
/* Turn off cputimer->running. This is done without locking. */
|
|
WRITE_ONCE(cputimer->running, false);
|
|
tick_dep_clear_signal(sig, TICK_DEP_BIT_POSIX_TIMER);
|
|
}
|
|
|
|
static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
|
|
u64 *expires, u64 cur_time, int signo)
|
|
{
|
|
if (!it->expires)
|
|
return;
|
|
|
|
if (cur_time >= it->expires) {
|
|
if (it->incr)
|
|
it->expires += it->incr;
|
|
else
|
|
it->expires = 0;
|
|
|
|
trace_itimer_expire(signo == SIGPROF ?
|
|
ITIMER_PROF : ITIMER_VIRTUAL,
|
|
task_tgid(tsk), cur_time);
|
|
__group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
|
|
}
|
|
|
|
if (it->expires && (!*expires || it->expires < *expires))
|
|
*expires = it->expires;
|
|
}
|
|
|
|
/*
|
|
* Check for any per-thread CPU timers that have fired and move them
|
|
* off the tsk->*_timers list onto the firing list. Per-thread timers
|
|
* have already been taken off.
|
|
*/
|
|
static void check_process_timers(struct task_struct *tsk,
|
|
struct list_head *firing)
|
|
{
|
|
struct signal_struct *const sig = tsk->signal;
|
|
u64 utime, ptime, virt_expires, prof_expires;
|
|
u64 sum_sched_runtime, sched_expires;
|
|
struct list_head *timers = sig->cpu_timers;
|
|
struct task_cputime cputime;
|
|
unsigned long soft;
|
|
|
|
if (dl_task(tsk))
|
|
check_dl_overrun(tsk);
|
|
|
|
/*
|
|
* If cputimer is not running, then there are no active
|
|
* process wide timers (POSIX 1.b, itimers, RLIMIT_CPU).
|
|
*/
|
|
if (!READ_ONCE(tsk->signal->cputimer.running))
|
|
return;
|
|
|
|
/*
|
|
* Signify that a thread is checking for process timers.
|
|
* Write access to this field is protected by the sighand lock.
|
|
*/
|
|
sig->cputimer.checking_timer = true;
|
|
|
|
/*
|
|
* Collect the current process totals.
|
|
*/
|
|
thread_group_cputimer(tsk, &cputime);
|
|
utime = cputime.utime;
|
|
ptime = utime + cputime.stime;
|
|
sum_sched_runtime = cputime.sum_exec_runtime;
|
|
|
|
prof_expires = check_timers_list(timers, firing, ptime);
|
|
virt_expires = check_timers_list(++timers, firing, utime);
|
|
sched_expires = check_timers_list(++timers, firing, sum_sched_runtime);
|
|
|
|
/*
|
|
* Check for the special case process timers.
|
|
*/
|
|
check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime,
|
|
SIGPROF);
|
|
check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime,
|
|
SIGVTALRM);
|
|
soft = task_rlimit(tsk, RLIMIT_CPU);
|
|
if (soft != RLIM_INFINITY) {
|
|
unsigned long psecs = div_u64(ptime, NSEC_PER_SEC);
|
|
unsigned long hard = task_rlimit_max(tsk, RLIMIT_CPU);
|
|
u64 x;
|
|
if (psecs >= hard) {
|
|
/*
|
|
* At the hard limit, we just die.
|
|
* No need to calculate anything else now.
|
|
*/
|
|
if (print_fatal_signals) {
|
|
pr_info("RT Watchdog Timeout (hard): %s[%d]\n",
|
|
tsk->comm, task_pid_nr(tsk));
|
|
}
|
|
__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
|
|
return;
|
|
}
|
|
if (psecs >= soft) {
|
|
/*
|
|
* At the soft limit, send a SIGXCPU every second.
|
|
*/
|
|
if (print_fatal_signals) {
|
|
pr_info("CPU Watchdog Timeout (soft): %s[%d]\n",
|
|
tsk->comm, task_pid_nr(tsk));
|
|
}
|
|
__group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
|
|
if (soft < hard) {
|
|
soft++;
|
|
sig->rlim[RLIMIT_CPU].rlim_cur = soft;
|
|
}
|
|
}
|
|
x = soft * NSEC_PER_SEC;
|
|
if (!prof_expires || x < prof_expires)
|
|
prof_expires = x;
|
|
}
|
|
|
|
sig->cputime_expires.prof_exp = prof_expires;
|
|
sig->cputime_expires.virt_exp = virt_expires;
|
|
sig->cputime_expires.sched_exp = sched_expires;
|
|
if (task_cputime_zero(&sig->cputime_expires))
|
|
stop_process_timers(sig);
|
|
|
|
sig->cputimer.checking_timer = false;
|
|
}
|
|
|
|
/*
|
|
* This is called from the signal code (via posixtimer_rearm)
|
|
* when the last timer signal was delivered and we have to reload the timer.
|
|
*/
|
|
static void posix_cpu_timer_rearm(struct k_itimer *timer)
|
|
{
|
|
struct sighand_struct *sighand;
|
|
unsigned long flags;
|
|
struct task_struct *p = timer->it.cpu.task;
|
|
u64 now;
|
|
|
|
WARN_ON_ONCE(p == NULL);
|
|
|
|
/*
|
|
* Fetch the current sample and update the timer's expiry time.
|
|
*/
|
|
if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
|
|
cpu_clock_sample(timer->it_clock, p, &now);
|
|
bump_cpu_timer(timer, now);
|
|
if (unlikely(p->exit_state))
|
|
return;
|
|
|
|
/* Protect timer list r/w in arm_timer() */
|
|
sighand = lock_task_sighand(p, &flags);
|
|
if (!sighand)
|
|
return;
|
|
} else {
|
|
/*
|
|
* Protect arm_timer() and timer sampling in case of call to
|
|
* thread_group_cputime().
|
|
*/
|
|
sighand = lock_task_sighand(p, &flags);
|
|
if (unlikely(sighand == NULL)) {
|
|
/*
|
|
* The process has been reaped.
|
|
* We can't even collect a sample any more.
|
|
*/
|
|
timer->it.cpu.expires = 0;
|
|
return;
|
|
} else if (unlikely(p->exit_state) && thread_group_empty(p)) {
|
|
/* If the process is dying, no need to rearm */
|
|
goto unlock;
|
|
}
|
|
cpu_timer_sample_group(timer->it_clock, p, &now);
|
|
bump_cpu_timer(timer, now);
|
|
/* Leave the sighand locked for the call below. */
|
|
}
|
|
|
|
/*
|
|
* Now re-arm for the new expiry time.
|
|
*/
|
|
arm_timer(timer);
|
|
unlock:
|
|
unlock_task_sighand(p, &flags);
|
|
}
|
|
|
|
/**
|
|
* task_cputime_expired - Compare two task_cputime entities.
|
|
*
|
|
* @sample: The task_cputime structure to be checked for expiration.
|
|
* @expires: Expiration times, against which @sample will be checked.
|
|
*
|
|
* Checks @sample against @expires to see if any field of @sample has expired.
|
|
* Returns true if any field of the former is greater than the corresponding
|
|
* field of the latter if the latter field is set. Otherwise returns false.
|
|
*/
|
|
static inline int task_cputime_expired(const struct task_cputime *sample,
|
|
const struct task_cputime *expires)
|
|
{
|
|
if (expires->utime && sample->utime >= expires->utime)
|
|
return 1;
|
|
if (expires->stime && sample->utime + sample->stime >= expires->stime)
|
|
return 1;
|
|
if (expires->sum_exec_runtime != 0 &&
|
|
sample->sum_exec_runtime >= expires->sum_exec_runtime)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* fastpath_timer_check - POSIX CPU timers fast path.
|
|
*
|
|
* @tsk: The task (thread) being checked.
|
|
*
|
|
* Check the task and thread group timers. If both are zero (there are no
|
|
* timers set) return false. Otherwise snapshot the task and thread group
|
|
* timers and compare them with the corresponding expiration times. Return
|
|
* true if a timer has expired, else return false.
|
|
*/
|
|
static inline int fastpath_timer_check(struct task_struct *tsk)
|
|
{
|
|
struct signal_struct *sig;
|
|
|
|
if (!task_cputime_zero(&tsk->cputime_expires)) {
|
|
struct task_cputime task_sample;
|
|
|
|
task_cputime(tsk, &task_sample.utime, &task_sample.stime);
|
|
task_sample.sum_exec_runtime = tsk->se.sum_exec_runtime;
|
|
if (task_cputime_expired(&task_sample, &tsk->cputime_expires))
|
|
return 1;
|
|
}
|
|
|
|
sig = tsk->signal;
|
|
/*
|
|
* Check if thread group timers expired when the cputimer is
|
|
* running and no other thread in the group is already checking
|
|
* for thread group cputimers. These fields are read without the
|
|
* sighand lock. However, this is fine because this is meant to
|
|
* be a fastpath heuristic to determine whether we should try to
|
|
* acquire the sighand lock to check/handle timers.
|
|
*
|
|
* In the worst case scenario, if 'running' or 'checking_timer' gets
|
|
* set but the current thread doesn't see the change yet, we'll wait
|
|
* until the next thread in the group gets a scheduler interrupt to
|
|
* handle the timer. This isn't an issue in practice because these
|
|
* types of delays with signals actually getting sent are expected.
|
|
*/
|
|
if (READ_ONCE(sig->cputimer.running) &&
|
|
!READ_ONCE(sig->cputimer.checking_timer)) {
|
|
struct task_cputime group_sample;
|
|
|
|
sample_cputime_atomic(&group_sample, &sig->cputimer.cputime_atomic);
|
|
|
|
if (task_cputime_expired(&group_sample, &sig->cputime_expires))
|
|
return 1;
|
|
}
|
|
|
|
if (dl_task(tsk) && tsk->dl.dl_overrun)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This is called from the timer interrupt handler. The irq handler has
|
|
* already updated our counts. We need to check if any timers fire now.
|
|
* Interrupts are disabled.
|
|
*/
|
|
void run_posix_cpu_timers(struct task_struct *tsk)
|
|
{
|
|
LIST_HEAD(firing);
|
|
struct k_itimer *timer, *next;
|
|
unsigned long flags;
|
|
|
|
lockdep_assert_irqs_disabled();
|
|
|
|
/*
|
|
* The fast path checks that there are no expired thread or thread
|
|
* group timers. If that's so, just return.
|
|
*/
|
|
if (!fastpath_timer_check(tsk))
|
|
return;
|
|
|
|
if (!lock_task_sighand(tsk, &flags))
|
|
return;
|
|
/*
|
|
* Here we take off tsk->signal->cpu_timers[N] and
|
|
* tsk->cpu_timers[N] all the timers that are firing, and
|
|
* put them on the firing list.
|
|
*/
|
|
check_thread_timers(tsk, &firing);
|
|
|
|
check_process_timers(tsk, &firing);
|
|
|
|
/*
|
|
* We must release these locks before taking any timer's lock.
|
|
* There is a potential race with timer deletion here, as the
|
|
* siglock now protects our private firing list. We have set
|
|
* the firing flag in each timer, so that a deletion attempt
|
|
* that gets the timer lock before we do will give it up and
|
|
* spin until we've taken care of that timer below.
|
|
*/
|
|
unlock_task_sighand(tsk, &flags);
|
|
|
|
/*
|
|
* Now that all the timers on our list have the firing flag,
|
|
* no one will touch their list entries but us. We'll take
|
|
* each timer's lock before clearing its firing flag, so no
|
|
* timer call will interfere.
|
|
*/
|
|
list_for_each_entry_safe(timer, next, &firing, it.cpu.entry) {
|
|
int cpu_firing;
|
|
|
|
spin_lock(&timer->it_lock);
|
|
list_del_init(&timer->it.cpu.entry);
|
|
cpu_firing = timer->it.cpu.firing;
|
|
timer->it.cpu.firing = 0;
|
|
/*
|
|
* The firing flag is -1 if we collided with a reset
|
|
* of the timer, which already reported this
|
|
* almost-firing as an overrun. So don't generate an event.
|
|
*/
|
|
if (likely(cpu_firing >= 0))
|
|
cpu_timer_fire(timer);
|
|
spin_unlock(&timer->it_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Set one of the process-wide special case CPU timers or RLIMIT_CPU.
|
|
* The tsk->sighand->siglock must be held by the caller.
|
|
*/
|
|
void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx,
|
|
u64 *newval, u64 *oldval)
|
|
{
|
|
u64 now;
|
|
int ret;
|
|
|
|
WARN_ON_ONCE(clock_idx == CPUCLOCK_SCHED);
|
|
ret = cpu_timer_sample_group(clock_idx, tsk, &now);
|
|
|
|
if (oldval && ret != -EINVAL) {
|
|
/*
|
|
* We are setting itimer. The *oldval is absolute and we update
|
|
* it to be relative, *newval argument is relative and we update
|
|
* it to be absolute.
|
|
*/
|
|
if (*oldval) {
|
|
if (*oldval <= now) {
|
|
/* Just about to fire. */
|
|
*oldval = TICK_NSEC;
|
|
} else {
|
|
*oldval -= now;
|
|
}
|
|
}
|
|
|
|
if (!*newval)
|
|
return;
|
|
*newval += now;
|
|
}
|
|
|
|
/*
|
|
* Update expiration cache if we are the earliest timer, or eventually
|
|
* RLIMIT_CPU limit is earlier than prof_exp cpu timer expire.
|
|
*/
|
|
switch (clock_idx) {
|
|
case CPUCLOCK_PROF:
|
|
if (expires_gt(tsk->signal->cputime_expires.prof_exp, *newval))
|
|
tsk->signal->cputime_expires.prof_exp = *newval;
|
|
break;
|
|
case CPUCLOCK_VIRT:
|
|
if (expires_gt(tsk->signal->cputime_expires.virt_exp, *newval))
|
|
tsk->signal->cputime_expires.virt_exp = *newval;
|
|
break;
|
|
}
|
|
|
|
tick_dep_set_signal(tsk->signal, TICK_DEP_BIT_POSIX_TIMER);
|
|
}
|
|
|
|
static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
|
|
const struct timespec64 *rqtp)
|
|
{
|
|
struct itimerspec64 it;
|
|
struct k_itimer timer;
|
|
u64 expires;
|
|
int error;
|
|
|
|
/*
|
|
* Set up a temporary timer and then wait for it to go off.
|
|
*/
|
|
memset(&timer, 0, sizeof timer);
|
|
spin_lock_init(&timer.it_lock);
|
|
timer.it_clock = which_clock;
|
|
timer.it_overrun = -1;
|
|
error = posix_cpu_timer_create(&timer);
|
|
timer.it_process = current;
|
|
if (!error) {
|
|
static struct itimerspec64 zero_it;
|
|
struct restart_block *restart;
|
|
|
|
memset(&it, 0, sizeof(it));
|
|
it.it_value = *rqtp;
|
|
|
|
spin_lock_irq(&timer.it_lock);
|
|
error = posix_cpu_timer_set(&timer, flags, &it, NULL);
|
|
if (error) {
|
|
spin_unlock_irq(&timer.it_lock);
|
|
return error;
|
|
}
|
|
|
|
while (!signal_pending(current)) {
|
|
if (timer.it.cpu.expires == 0) {
|
|
/*
|
|
* Our timer fired and was reset, below
|
|
* deletion can not fail.
|
|
*/
|
|
posix_cpu_timer_del(&timer);
|
|
spin_unlock_irq(&timer.it_lock);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Block until cpu_timer_fire (or a signal) wakes us.
|
|
*/
|
|
__set_current_state(TASK_INTERRUPTIBLE);
|
|
spin_unlock_irq(&timer.it_lock);
|
|
schedule();
|
|
spin_lock_irq(&timer.it_lock);
|
|
}
|
|
|
|
/*
|
|
* We were interrupted by a signal.
|
|
*/
|
|
expires = timer.it.cpu.expires;
|
|
error = posix_cpu_timer_set(&timer, 0, &zero_it, &it);
|
|
if (!error) {
|
|
/*
|
|
* Timer is now unarmed, deletion can not fail.
|
|
*/
|
|
posix_cpu_timer_del(&timer);
|
|
}
|
|
spin_unlock_irq(&timer.it_lock);
|
|
|
|
while (error == TIMER_RETRY) {
|
|
/*
|
|
* We need to handle case when timer was or is in the
|
|
* middle of firing. In other cases we already freed
|
|
* resources.
|
|
*/
|
|
spin_lock_irq(&timer.it_lock);
|
|
error = posix_cpu_timer_del(&timer);
|
|
spin_unlock_irq(&timer.it_lock);
|
|
}
|
|
|
|
if ((it.it_value.tv_sec | it.it_value.tv_nsec) == 0) {
|
|
/*
|
|
* It actually did fire already.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
error = -ERESTART_RESTARTBLOCK;
|
|
/*
|
|
* Report back to the user the time still remaining.
|
|
*/
|
|
restart = ¤t->restart_block;
|
|
restart->nanosleep.expires = expires;
|
|
if (restart->nanosleep.type != TT_NONE)
|
|
error = nanosleep_copyout(restart, &it.it_value);
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
static long posix_cpu_nsleep_restart(struct restart_block *restart_block);
|
|
|
|
static int posix_cpu_nsleep(const clockid_t which_clock, int flags,
|
|
const struct timespec64 *rqtp)
|
|
{
|
|
struct restart_block *restart_block = ¤t->restart_block;
|
|
int error;
|
|
|
|
/*
|
|
* Diagnose required errors first.
|
|
*/
|
|
if (CPUCLOCK_PERTHREAD(which_clock) &&
|
|
(CPUCLOCK_PID(which_clock) == 0 ||
|
|
CPUCLOCK_PID(which_clock) == task_pid_vnr(current)))
|
|
return -EINVAL;
|
|
|
|
error = do_cpu_nanosleep(which_clock, flags, rqtp);
|
|
|
|
if (error == -ERESTART_RESTARTBLOCK) {
|
|
|
|
if (flags & TIMER_ABSTIME)
|
|
return -ERESTARTNOHAND;
|
|
|
|
restart_block->fn = posix_cpu_nsleep_restart;
|
|
restart_block->nanosleep.clockid = which_clock;
|
|
}
|
|
return error;
|
|
}
|
|
|
|
static long posix_cpu_nsleep_restart(struct restart_block *restart_block)
|
|
{
|
|
clockid_t which_clock = restart_block->nanosleep.clockid;
|
|
struct timespec64 t;
|
|
|
|
t = ns_to_timespec64(restart_block->nanosleep.expires);
|
|
|
|
return do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t);
|
|
}
|
|
|
|
#define PROCESS_CLOCK make_process_cpuclock(0, CPUCLOCK_SCHED)
|
|
#define THREAD_CLOCK make_thread_cpuclock(0, CPUCLOCK_SCHED)
|
|
|
|
static int process_cpu_clock_getres(const clockid_t which_clock,
|
|
struct timespec64 *tp)
|
|
{
|
|
return posix_cpu_clock_getres(PROCESS_CLOCK, tp);
|
|
}
|
|
static int process_cpu_clock_get(const clockid_t which_clock,
|
|
struct timespec64 *tp)
|
|
{
|
|
return posix_cpu_clock_get(PROCESS_CLOCK, tp);
|
|
}
|
|
static int process_cpu_timer_create(struct k_itimer *timer)
|
|
{
|
|
timer->it_clock = PROCESS_CLOCK;
|
|
return posix_cpu_timer_create(timer);
|
|
}
|
|
static int process_cpu_nsleep(const clockid_t which_clock, int flags,
|
|
const struct timespec64 *rqtp)
|
|
{
|
|
return posix_cpu_nsleep(PROCESS_CLOCK, flags, rqtp);
|
|
}
|
|
static int thread_cpu_clock_getres(const clockid_t which_clock,
|
|
struct timespec64 *tp)
|
|
{
|
|
return posix_cpu_clock_getres(THREAD_CLOCK, tp);
|
|
}
|
|
static int thread_cpu_clock_get(const clockid_t which_clock,
|
|
struct timespec64 *tp)
|
|
{
|
|
return posix_cpu_clock_get(THREAD_CLOCK, tp);
|
|
}
|
|
static int thread_cpu_timer_create(struct k_itimer *timer)
|
|
{
|
|
timer->it_clock = THREAD_CLOCK;
|
|
return posix_cpu_timer_create(timer);
|
|
}
|
|
|
|
const struct k_clock clock_posix_cpu = {
|
|
.clock_getres = posix_cpu_clock_getres,
|
|
.clock_set = posix_cpu_clock_set,
|
|
.clock_get = posix_cpu_clock_get,
|
|
.timer_create = posix_cpu_timer_create,
|
|
.nsleep = posix_cpu_nsleep,
|
|
.timer_set = posix_cpu_timer_set,
|
|
.timer_del = posix_cpu_timer_del,
|
|
.timer_get = posix_cpu_timer_get,
|
|
.timer_rearm = posix_cpu_timer_rearm,
|
|
};
|
|
|
|
const struct k_clock clock_process = {
|
|
.clock_getres = process_cpu_clock_getres,
|
|
.clock_get = process_cpu_clock_get,
|
|
.timer_create = process_cpu_timer_create,
|
|
.nsleep = process_cpu_nsleep,
|
|
};
|
|
|
|
const struct k_clock clock_thread = {
|
|
.clock_getres = thread_cpu_clock_getres,
|
|
.clock_get = thread_cpu_clock_get,
|
|
.timer_create = thread_cpu_timer_create,
|
|
};
|