![Eric W. Biederman](/assets/img/avatar_default.png)
Create an independent helper thread_group_exited which returns true when all threads have passed exit_notify in do_exit. AKA all of the threads are at least zombies and might be dead or completely gone. Create this helper by taking the logic out of pidfd_poll where it is already tested, and adding a READ_ONCE on the read of task->exit_state. I will be changing the user mode driver code to use this same logic to know when a user mode driver needs to be restarted. Place the new helper thread_group_exited in kernel/exit.c and EXPORT it so it can be used by modules. Link: https://lkml.kernel.org/r/20200702164140.4468-13-ebiederm@xmission.com Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
721 lines
20 KiB
C
721 lines
20 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_SCHED_SIGNAL_H
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#define _LINUX_SCHED_SIGNAL_H
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#include <linux/rculist.h>
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#include <linux/signal.h>
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#include <linux/sched.h>
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#include <linux/sched/jobctl.h>
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#include <linux/sched/task.h>
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#include <linux/cred.h>
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#include <linux/refcount.h>
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#include <linux/posix-timers.h>
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#include <linux/mm_types.h>
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#include <asm/ptrace.h>
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/*
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* Types defining task->signal and task->sighand and APIs using them:
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*/
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struct sighand_struct {
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spinlock_t siglock;
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refcount_t count;
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wait_queue_head_t signalfd_wqh;
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struct k_sigaction action[_NSIG];
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};
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/*
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* Per-process accounting stats:
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*/
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struct pacct_struct {
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int ac_flag;
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long ac_exitcode;
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unsigned long ac_mem;
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u64 ac_utime, ac_stime;
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unsigned long ac_minflt, ac_majflt;
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};
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struct cpu_itimer {
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u64 expires;
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u64 incr;
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};
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/*
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* This is the atomic variant of task_cputime, which can be used for
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* storing and updating task_cputime statistics without locking.
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*/
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struct task_cputime_atomic {
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atomic64_t utime;
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atomic64_t stime;
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atomic64_t sum_exec_runtime;
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};
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#define INIT_CPUTIME_ATOMIC \
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(struct task_cputime_atomic) { \
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.utime = ATOMIC64_INIT(0), \
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.stime = ATOMIC64_INIT(0), \
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.sum_exec_runtime = ATOMIC64_INIT(0), \
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}
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/**
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* struct thread_group_cputimer - thread group interval timer counts
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* @cputime_atomic: atomic thread group interval timers.
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*
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* This structure contains the version of task_cputime, above, that is
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* used for thread group CPU timer calculations.
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*/
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struct thread_group_cputimer {
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struct task_cputime_atomic cputime_atomic;
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};
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struct multiprocess_signals {
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sigset_t signal;
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struct hlist_node node;
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};
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/*
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* NOTE! "signal_struct" does not have its own
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* locking, because a shared signal_struct always
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* implies a shared sighand_struct, so locking
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* sighand_struct is always a proper superset of
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* the locking of signal_struct.
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*/
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struct signal_struct {
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refcount_t sigcnt;
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atomic_t live;
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int nr_threads;
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struct list_head thread_head;
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wait_queue_head_t wait_chldexit; /* for wait4() */
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/* current thread group signal load-balancing target: */
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struct task_struct *curr_target;
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/* shared signal handling: */
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struct sigpending shared_pending;
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/* For collecting multiprocess signals during fork */
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struct hlist_head multiprocess;
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/* thread group exit support */
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int group_exit_code;
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/* overloaded:
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* - notify group_exit_task when ->count is equal to notify_count
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* - everyone except group_exit_task is stopped during signal delivery
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* of fatal signals, group_exit_task processes the signal.
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*/
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int notify_count;
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struct task_struct *group_exit_task;
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/* thread group stop support, overloads group_exit_code too */
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int group_stop_count;
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unsigned int flags; /* see SIGNAL_* flags below */
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/*
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* PR_SET_CHILD_SUBREAPER marks a process, like a service
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* manager, to re-parent orphan (double-forking) child processes
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* to this process instead of 'init'. The service manager is
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* able to receive SIGCHLD signals and is able to investigate
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* the process until it calls wait(). All children of this
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* process will inherit a flag if they should look for a
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* child_subreaper process at exit.
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*/
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unsigned int is_child_subreaper:1;
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unsigned int has_child_subreaper:1;
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#ifdef CONFIG_POSIX_TIMERS
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/* POSIX.1b Interval Timers */
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int posix_timer_id;
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struct list_head posix_timers;
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/* ITIMER_REAL timer for the process */
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struct hrtimer real_timer;
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ktime_t it_real_incr;
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/*
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* ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
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* CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
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* values are defined to 0 and 1 respectively
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*/
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struct cpu_itimer it[2];
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/*
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* Thread group totals for process CPU timers.
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* See thread_group_cputimer(), et al, for details.
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*/
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struct thread_group_cputimer cputimer;
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#endif
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/* Empty if CONFIG_POSIX_TIMERS=n */
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struct posix_cputimers posix_cputimers;
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/* PID/PID hash table linkage. */
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struct pid *pids[PIDTYPE_MAX];
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#ifdef CONFIG_NO_HZ_FULL
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atomic_t tick_dep_mask;
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#endif
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struct pid *tty_old_pgrp;
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/* boolean value for session group leader */
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int leader;
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struct tty_struct *tty; /* NULL if no tty */
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#ifdef CONFIG_SCHED_AUTOGROUP
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struct autogroup *autogroup;
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#endif
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/*
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* Cumulative resource counters for dead threads in the group,
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* and for reaped dead child processes forked by this group.
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* Live threads maintain their own counters and add to these
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* in __exit_signal, except for the group leader.
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*/
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seqlock_t stats_lock;
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u64 utime, stime, cutime, cstime;
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u64 gtime;
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u64 cgtime;
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struct prev_cputime prev_cputime;
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unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
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unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
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unsigned long inblock, oublock, cinblock, coublock;
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unsigned long maxrss, cmaxrss;
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struct task_io_accounting ioac;
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/*
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* Cumulative ns of schedule CPU time fo dead threads in the
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* group, not including a zombie group leader, (This only differs
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* from jiffies_to_ns(utime + stime) if sched_clock uses something
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* other than jiffies.)
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*/
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unsigned long long sum_sched_runtime;
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/*
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* We don't bother to synchronize most readers of this at all,
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* because there is no reader checking a limit that actually needs
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* to get both rlim_cur and rlim_max atomically, and either one
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* alone is a single word that can safely be read normally.
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* getrlimit/setrlimit use task_lock(current->group_leader) to
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* protect this instead of the siglock, because they really
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* have no need to disable irqs.
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*/
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struct rlimit rlim[RLIM_NLIMITS];
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#ifdef CONFIG_BSD_PROCESS_ACCT
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struct pacct_struct pacct; /* per-process accounting information */
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#endif
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#ifdef CONFIG_TASKSTATS
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struct taskstats *stats;
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#endif
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#ifdef CONFIG_AUDIT
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unsigned audit_tty;
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struct tty_audit_buf *tty_audit_buf;
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#endif
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/*
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* Thread is the potential origin of an oom condition; kill first on
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* oom
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*/
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bool oom_flag_origin;
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short oom_score_adj; /* OOM kill score adjustment */
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short oom_score_adj_min; /* OOM kill score adjustment min value.
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* Only settable by CAP_SYS_RESOURCE. */
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struct mm_struct *oom_mm; /* recorded mm when the thread group got
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* killed by the oom killer */
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struct mutex cred_guard_mutex; /* guard against foreign influences on
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* credential calculations
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* (notably. ptrace)
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* Deprecated do not use in new code.
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* Use exec_update_mutex instead.
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*/
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struct mutex exec_update_mutex; /* Held while task_struct is being
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* updated during exec, and may have
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* inconsistent permissions.
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*/
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} __randomize_layout;
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/*
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* Bits in flags field of signal_struct.
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*/
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#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
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#define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */
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#define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */
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#define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */
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/*
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* Pending notifications to parent.
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*/
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#define SIGNAL_CLD_STOPPED 0x00000010
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#define SIGNAL_CLD_CONTINUED 0x00000020
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#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
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#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
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#define SIGNAL_STOP_MASK (SIGNAL_CLD_MASK | SIGNAL_STOP_STOPPED | \
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SIGNAL_STOP_CONTINUED)
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static inline void signal_set_stop_flags(struct signal_struct *sig,
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unsigned int flags)
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{
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WARN_ON(sig->flags & (SIGNAL_GROUP_EXIT|SIGNAL_GROUP_COREDUMP));
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sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags;
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}
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/* If true, all threads except ->group_exit_task have pending SIGKILL */
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static inline int signal_group_exit(const struct signal_struct *sig)
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{
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return (sig->flags & SIGNAL_GROUP_EXIT) ||
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(sig->group_exit_task != NULL);
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}
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extern void flush_signals(struct task_struct *);
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extern void ignore_signals(struct task_struct *);
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extern void flush_signal_handlers(struct task_struct *, int force_default);
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extern int dequeue_signal(struct task_struct *task,
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sigset_t *mask, kernel_siginfo_t *info);
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static inline int kernel_dequeue_signal(void)
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{
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struct task_struct *task = current;
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kernel_siginfo_t __info;
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int ret;
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spin_lock_irq(&task->sighand->siglock);
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ret = dequeue_signal(task, &task->blocked, &__info);
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spin_unlock_irq(&task->sighand->siglock);
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return ret;
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}
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static inline void kernel_signal_stop(void)
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{
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spin_lock_irq(¤t->sighand->siglock);
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if (current->jobctl & JOBCTL_STOP_DEQUEUED)
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set_special_state(TASK_STOPPED);
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spin_unlock_irq(¤t->sighand->siglock);
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schedule();
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}
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#ifdef __ARCH_SI_TRAPNO
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# define ___ARCH_SI_TRAPNO(_a1) , _a1
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#else
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# define ___ARCH_SI_TRAPNO(_a1)
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#endif
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#ifdef __ia64__
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# define ___ARCH_SI_IA64(_a1, _a2, _a3) , _a1, _a2, _a3
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#else
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# define ___ARCH_SI_IA64(_a1, _a2, _a3)
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#endif
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int force_sig_fault_to_task(int sig, int code, void __user *addr
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___ARCH_SI_TRAPNO(int trapno)
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___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
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, struct task_struct *t);
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int force_sig_fault(int sig, int code, void __user *addr
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___ARCH_SI_TRAPNO(int trapno)
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___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr));
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int send_sig_fault(int sig, int code, void __user *addr
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___ARCH_SI_TRAPNO(int trapno)
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___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
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, struct task_struct *t);
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int force_sig_mceerr(int code, void __user *, short);
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int send_sig_mceerr(int code, void __user *, short, struct task_struct *);
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int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper);
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int force_sig_pkuerr(void __user *addr, u32 pkey);
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int force_sig_ptrace_errno_trap(int errno, void __user *addr);
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extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *);
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extern void force_sigsegv(int sig);
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extern int force_sig_info(struct kernel_siginfo *);
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extern int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp);
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extern int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid);
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extern int kill_pid_usb_asyncio(int sig, int errno, sigval_t addr, struct pid *,
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const struct cred *);
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extern int kill_pgrp(struct pid *pid, int sig, int priv);
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extern int kill_pid(struct pid *pid, int sig, int priv);
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extern __must_check bool do_notify_parent(struct task_struct *, int);
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extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
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extern void force_sig(int);
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extern int send_sig(int, struct task_struct *, int);
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extern int zap_other_threads(struct task_struct *p);
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extern struct sigqueue *sigqueue_alloc(void);
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extern void sigqueue_free(struct sigqueue *);
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extern int send_sigqueue(struct sigqueue *, struct pid *, enum pid_type);
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extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
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static inline int restart_syscall(void)
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{
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set_tsk_thread_flag(current, TIF_SIGPENDING);
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return -ERESTARTNOINTR;
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}
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static inline int signal_pending(struct task_struct *p)
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{
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return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
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}
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static inline int __fatal_signal_pending(struct task_struct *p)
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{
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return unlikely(sigismember(&p->pending.signal, SIGKILL));
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}
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static inline int fatal_signal_pending(struct task_struct *p)
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{
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return signal_pending(p) && __fatal_signal_pending(p);
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}
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static inline int signal_pending_state(long state, struct task_struct *p)
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{
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if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
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return 0;
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if (!signal_pending(p))
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return 0;
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return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
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}
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/*
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* This should only be used in fault handlers to decide whether we
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* should stop the current fault routine to handle the signals
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* instead, especially with the case where we've got interrupted with
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* a VM_FAULT_RETRY.
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*/
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static inline bool fault_signal_pending(vm_fault_t fault_flags,
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struct pt_regs *regs)
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{
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return unlikely((fault_flags & VM_FAULT_RETRY) &&
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(fatal_signal_pending(current) ||
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(user_mode(regs) && signal_pending(current))));
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}
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/*
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* Reevaluate whether the task has signals pending delivery.
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* Wake the task if so.
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* This is required every time the blocked sigset_t changes.
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* callers must hold sighand->siglock.
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*/
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extern void recalc_sigpending_and_wake(struct task_struct *t);
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extern void recalc_sigpending(void);
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extern void calculate_sigpending(void);
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extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
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static inline void signal_wake_up(struct task_struct *t, bool resume)
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{
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signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
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}
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static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
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{
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signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
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}
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void task_join_group_stop(struct task_struct *task);
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#ifdef TIF_RESTORE_SIGMASK
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/*
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* Legacy restore_sigmask accessors. These are inefficient on
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* SMP architectures because they require atomic operations.
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*/
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/**
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* set_restore_sigmask() - make sure saved_sigmask processing gets done
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*
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* This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
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* will run before returning to user mode, to process the flag. For
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* all callers, TIF_SIGPENDING is already set or it's no harm to set
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* it. TIF_RESTORE_SIGMASK need not be in the set of bits that the
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* arch code will notice on return to user mode, in case those bits
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* are scarce. We set TIF_SIGPENDING here to ensure that the arch
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* signal code always gets run when TIF_RESTORE_SIGMASK is set.
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*/
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static inline void set_restore_sigmask(void)
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{
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set_thread_flag(TIF_RESTORE_SIGMASK);
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}
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static inline void clear_tsk_restore_sigmask(struct task_struct *task)
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{
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clear_tsk_thread_flag(task, TIF_RESTORE_SIGMASK);
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}
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static inline void clear_restore_sigmask(void)
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{
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clear_thread_flag(TIF_RESTORE_SIGMASK);
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}
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static inline bool test_tsk_restore_sigmask(struct task_struct *task)
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{
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return test_tsk_thread_flag(task, TIF_RESTORE_SIGMASK);
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}
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static inline bool test_restore_sigmask(void)
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{
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return test_thread_flag(TIF_RESTORE_SIGMASK);
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}
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static inline bool test_and_clear_restore_sigmask(void)
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{
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return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
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}
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#else /* TIF_RESTORE_SIGMASK */
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/* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */
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static inline void set_restore_sigmask(void)
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{
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current->restore_sigmask = true;
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}
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static inline void clear_tsk_restore_sigmask(struct task_struct *task)
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{
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task->restore_sigmask = false;
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}
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static inline void clear_restore_sigmask(void)
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{
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current->restore_sigmask = false;
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}
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static inline bool test_restore_sigmask(void)
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{
|
|
return current->restore_sigmask;
|
|
}
|
|
static inline bool test_tsk_restore_sigmask(struct task_struct *task)
|
|
{
|
|
return task->restore_sigmask;
|
|
}
|
|
static inline bool test_and_clear_restore_sigmask(void)
|
|
{
|
|
if (!current->restore_sigmask)
|
|
return false;
|
|
current->restore_sigmask = false;
|
|
return true;
|
|
}
|
|
#endif
|
|
|
|
static inline void restore_saved_sigmask(void)
|
|
{
|
|
if (test_and_clear_restore_sigmask())
|
|
__set_current_blocked(¤t->saved_sigmask);
|
|
}
|
|
|
|
extern int set_user_sigmask(const sigset_t __user *umask, size_t sigsetsize);
|
|
|
|
static inline void restore_saved_sigmask_unless(bool interrupted)
|
|
{
|
|
if (interrupted)
|
|
WARN_ON(!test_thread_flag(TIF_SIGPENDING));
|
|
else
|
|
restore_saved_sigmask();
|
|
}
|
|
|
|
static inline sigset_t *sigmask_to_save(void)
|
|
{
|
|
sigset_t *res = ¤t->blocked;
|
|
if (unlikely(test_restore_sigmask()))
|
|
res = ¤t->saved_sigmask;
|
|
return res;
|
|
}
|
|
|
|
static inline int kill_cad_pid(int sig, int priv)
|
|
{
|
|
return kill_pid(cad_pid, sig, priv);
|
|
}
|
|
|
|
/* These can be the second arg to send_sig_info/send_group_sig_info. */
|
|
#define SEND_SIG_NOINFO ((struct kernel_siginfo *) 0)
|
|
#define SEND_SIG_PRIV ((struct kernel_siginfo *) 1)
|
|
|
|
/*
|
|
* True if we are on the alternate signal stack.
|
|
*/
|
|
static inline int on_sig_stack(unsigned long sp)
|
|
{
|
|
/*
|
|
* If the signal stack is SS_AUTODISARM then, by construction, we
|
|
* can't be on the signal stack unless user code deliberately set
|
|
* SS_AUTODISARM when we were already on it.
|
|
*
|
|
* This improves reliability: if user state gets corrupted such that
|
|
* the stack pointer points very close to the end of the signal stack,
|
|
* then this check will enable the signal to be handled anyway.
|
|
*/
|
|
if (current->sas_ss_flags & SS_AUTODISARM)
|
|
return 0;
|
|
|
|
#ifdef CONFIG_STACK_GROWSUP
|
|
return sp >= current->sas_ss_sp &&
|
|
sp - current->sas_ss_sp < current->sas_ss_size;
|
|
#else
|
|
return sp > current->sas_ss_sp &&
|
|
sp - current->sas_ss_sp <= current->sas_ss_size;
|
|
#endif
|
|
}
|
|
|
|
static inline int sas_ss_flags(unsigned long sp)
|
|
{
|
|
if (!current->sas_ss_size)
|
|
return SS_DISABLE;
|
|
|
|
return on_sig_stack(sp) ? SS_ONSTACK : 0;
|
|
}
|
|
|
|
static inline void sas_ss_reset(struct task_struct *p)
|
|
{
|
|
p->sas_ss_sp = 0;
|
|
p->sas_ss_size = 0;
|
|
p->sas_ss_flags = SS_DISABLE;
|
|
}
|
|
|
|
static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
|
|
{
|
|
if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
|
|
#ifdef CONFIG_STACK_GROWSUP
|
|
return current->sas_ss_sp;
|
|
#else
|
|
return current->sas_ss_sp + current->sas_ss_size;
|
|
#endif
|
|
return sp;
|
|
}
|
|
|
|
extern void __cleanup_sighand(struct sighand_struct *);
|
|
extern void flush_itimer_signals(void);
|
|
|
|
#define tasklist_empty() \
|
|
list_empty(&init_task.tasks)
|
|
|
|
#define next_task(p) \
|
|
list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
|
|
|
|
#define for_each_process(p) \
|
|
for (p = &init_task ; (p = next_task(p)) != &init_task ; )
|
|
|
|
extern bool current_is_single_threaded(void);
|
|
|
|
/*
|
|
* Careful: do_each_thread/while_each_thread is a double loop so
|
|
* 'break' will not work as expected - use goto instead.
|
|
*/
|
|
#define do_each_thread(g, t) \
|
|
for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
|
|
|
|
#define while_each_thread(g, t) \
|
|
while ((t = next_thread(t)) != g)
|
|
|
|
#define __for_each_thread(signal, t) \
|
|
list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
|
|
|
|
#define for_each_thread(p, t) \
|
|
__for_each_thread((p)->signal, t)
|
|
|
|
/* Careful: this is a double loop, 'break' won't work as expected. */
|
|
#define for_each_process_thread(p, t) \
|
|
for_each_process(p) for_each_thread(p, t)
|
|
|
|
typedef int (*proc_visitor)(struct task_struct *p, void *data);
|
|
void walk_process_tree(struct task_struct *top, proc_visitor, void *);
|
|
|
|
static inline
|
|
struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
|
|
{
|
|
struct pid *pid;
|
|
if (type == PIDTYPE_PID)
|
|
pid = task_pid(task);
|
|
else
|
|
pid = task->signal->pids[type];
|
|
return pid;
|
|
}
|
|
|
|
static inline struct pid *task_tgid(struct task_struct *task)
|
|
{
|
|
return task->signal->pids[PIDTYPE_TGID];
|
|
}
|
|
|
|
/*
|
|
* Without tasklist or RCU lock it is not safe to dereference
|
|
* the result of task_pgrp/task_session even if task == current,
|
|
* we can race with another thread doing sys_setsid/sys_setpgid.
|
|
*/
|
|
static inline struct pid *task_pgrp(struct task_struct *task)
|
|
{
|
|
return task->signal->pids[PIDTYPE_PGID];
|
|
}
|
|
|
|
static inline struct pid *task_session(struct task_struct *task)
|
|
{
|
|
return task->signal->pids[PIDTYPE_SID];
|
|
}
|
|
|
|
static inline int get_nr_threads(struct task_struct *task)
|
|
{
|
|
return task->signal->nr_threads;
|
|
}
|
|
|
|
static inline bool thread_group_leader(struct task_struct *p)
|
|
{
|
|
return p->exit_signal >= 0;
|
|
}
|
|
|
|
static inline
|
|
bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
|
|
{
|
|
return p1->signal == p2->signal;
|
|
}
|
|
|
|
static inline struct task_struct *next_thread(const struct task_struct *p)
|
|
{
|
|
return list_entry_rcu(p->thread_group.next,
|
|
struct task_struct, thread_group);
|
|
}
|
|
|
|
static inline int thread_group_empty(struct task_struct *p)
|
|
{
|
|
return list_empty(&p->thread_group);
|
|
}
|
|
|
|
#define delay_group_leader(p) \
|
|
(thread_group_leader(p) && !thread_group_empty(p))
|
|
|
|
extern bool thread_group_exited(struct pid *pid);
|
|
|
|
extern struct sighand_struct *__lock_task_sighand(struct task_struct *task,
|
|
unsigned long *flags);
|
|
|
|
static inline struct sighand_struct *lock_task_sighand(struct task_struct *task,
|
|
unsigned long *flags)
|
|
{
|
|
struct sighand_struct *ret;
|
|
|
|
ret = __lock_task_sighand(task, flags);
|
|
(void)__cond_lock(&task->sighand->siglock, ret);
|
|
return ret;
|
|
}
|
|
|
|
static inline void unlock_task_sighand(struct task_struct *task,
|
|
unsigned long *flags)
|
|
{
|
|
spin_unlock_irqrestore(&task->sighand->siglock, *flags);
|
|
}
|
|
|
|
static inline unsigned long task_rlimit(const struct task_struct *task,
|
|
unsigned int limit)
|
|
{
|
|
return READ_ONCE(task->signal->rlim[limit].rlim_cur);
|
|
}
|
|
|
|
static inline unsigned long task_rlimit_max(const struct task_struct *task,
|
|
unsigned int limit)
|
|
{
|
|
return READ_ONCE(task->signal->rlim[limit].rlim_max);
|
|
}
|
|
|
|
static inline unsigned long rlimit(unsigned int limit)
|
|
{
|
|
return task_rlimit(current, limit);
|
|
}
|
|
|
|
static inline unsigned long rlimit_max(unsigned int limit)
|
|
{
|
|
return task_rlimit_max(current, limit);
|
|
}
|
|
|
|
#endif /* _LINUX_SCHED_SIGNAL_H */
|