* Copyright (C) 1991, 1992 Linus Torvalds
*/
-#include <linux/config.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/security.h>
#include <linux/cpu.h>
#include <linux/acct.h>
+#include <linux/tsacct_kern.h>
#include <linux/file.h>
#include <linux/binfmts.h>
+#include <linux/nsproxy.h>
#include <linux/ptrace.h>
#include <linux/profile.h>
#include <linux/mount.h>
#include <linux/proc_fs.h>
#include <linux/mempolicy.h>
+#include <linux/taskstats_kern.h>
+#include <linux/delayacct.h>
#include <linux/cpuset.h>
#include <linux/syscalls.h>
#include <linux/signal.h>
+#include <linux/posix-timers.h>
#include <linux/cn_proc.h>
#include <linux/mutex.h>
#include <linux/futex.h>
#include <linux/compat.h>
+#include <linux/pipe_fs_i.h>
+#include <linux/audit.h> /* for audit_free() */
+#include <linux/resource.h>
+#include <linux/blkdev.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
extern void sem_exit (void);
extern struct task_struct *child_reaper;
-int getrusage(struct task_struct *, int, struct rusage __user *);
-
static void exit_mm(struct task_struct * tsk);
static void __unhash_process(struct task_struct *p)
{
nr_threads--;
detach_pid(p, PIDTYPE_PID);
- detach_pid(p, PIDTYPE_TGID);
if (thread_group_leader(p)) {
detach_pid(p, PIDTYPE_PGID);
detach_pid(p, PIDTYPE_SID);
- list_del_init(&p->tasks);
- if (p->pid)
- __get_cpu_var(process_counts)--;
+ list_del_rcu(&p->tasks);
+ __get_cpu_var(process_counts)--;
}
-
+ list_del_rcu(&p->thread_group);
remove_parent(p);
}
+/*
+ * This function expects the tasklist_lock write-locked.
+ */
+static void __exit_signal(struct task_struct *tsk)
+{
+ struct signal_struct *sig = tsk->signal;
+ struct sighand_struct *sighand;
+
+ BUG_ON(!sig);
+ BUG_ON(!atomic_read(&sig->count));
+
+ rcu_read_lock();
+ sighand = rcu_dereference(tsk->sighand);
+ spin_lock(&sighand->siglock);
+
+ posix_cpu_timers_exit(tsk);
+ if (atomic_dec_and_test(&sig->count))
+ posix_cpu_timers_exit_group(tsk);
+ else {
+ /*
+ * If there is any task waiting for the group exit
+ * then notify it:
+ */
+ if (sig->group_exit_task && atomic_read(&sig->count) == sig->notify_count) {
+ wake_up_process(sig->group_exit_task);
+ sig->group_exit_task = NULL;
+ }
+ if (tsk == sig->curr_target)
+ sig->curr_target = next_thread(tsk);
+ /*
+ * Accumulate here the counters for all threads but the
+ * group leader as they die, so they can be added into
+ * the process-wide totals when those are taken.
+ * The group leader stays around as a zombie as long
+ * as there are other threads. When it gets reaped,
+ * the exit.c code will add its counts into these totals.
+ * We won't ever get here for the group leader, since it
+ * will have been the last reference on the signal_struct.
+ */
+ sig->utime = cputime_add(sig->utime, tsk->utime);
+ sig->stime = cputime_add(sig->stime, tsk->stime);
+ sig->min_flt += tsk->min_flt;
+ sig->maj_flt += tsk->maj_flt;
+ sig->nvcsw += tsk->nvcsw;
+ sig->nivcsw += tsk->nivcsw;
+ sig->sched_time += tsk->sched_time;
+ sig = NULL; /* Marker for below. */
+ }
+
+ __unhash_process(tsk);
+
+ tsk->signal = NULL;
+ tsk->sighand = NULL;
+ spin_unlock(&sighand->siglock);
+ rcu_read_unlock();
+
+ __cleanup_sighand(sighand);
+ clear_tsk_thread_flag(tsk,TIF_SIGPENDING);
+ flush_sigqueue(&tsk->pending);
+ if (sig) {
+ flush_sigqueue(&sig->shared_pending);
+ __cleanup_signal(sig);
+ }
+}
+
+static void delayed_put_task_struct(struct rcu_head *rhp)
+{
+ put_task_struct(container_of(rhp, struct task_struct, rcu));
+}
+
void release_task(struct task_struct * p)
{
+ struct task_struct *leader;
int zap_leader;
- task_t *leader;
- struct dentry *proc_dentry;
-
-repeat:
+repeat:
atomic_dec(&p->user->processes);
- spin_lock(&p->proc_lock);
- proc_dentry = proc_pid_unhash(p);
write_lock_irq(&tasklist_lock);
- if (unlikely(p->ptrace))
- __ptrace_unlink(p);
+ ptrace_unlink(p);
BUG_ON(!list_empty(&p->ptrace_list) || !list_empty(&p->ptrace_children));
__exit_signal(p);
- /*
- * Note that the fastpath in sys_times depends on __exit_signal having
- * updated the counters before a task is removed from the tasklist of
- * the process by __unhash_process.
- */
- __unhash_process(p);
/*
* If we are the last non-leader member of the thread
sched_exit(p);
write_unlock_irq(&tasklist_lock);
- spin_unlock(&p->proc_lock);
- proc_pid_flush(proc_dentry);
+ proc_flush_task(p);
release_thread(p);
- put_task_struct(p);
+ call_rcu(&p->rcu, delayed_put_task_struct);
p = leader;
if (unlikely(zap_leader))
goto repeat;
}
-/* we are using it only for SMP init */
-
-void unhash_process(struct task_struct *p)
-{
- struct dentry *proc_dentry;
-
- spin_lock(&p->proc_lock);
- proc_dentry = proc_pid_unhash(p);
- write_lock_irq(&tasklist_lock);
- __unhash_process(p);
- write_unlock_irq(&tasklist_lock);
- spin_unlock(&p->proc_lock);
- proc_pid_flush(proc_dentry);
-}
-
/*
* This checks not only the pgrp, but falls back on the pid if no
* satisfactory pgrp is found. I dunno - gdb doesn't work correctly
*
* "I ask you, have you ever known what it is to be an orphan?"
*/
-static int will_become_orphaned_pgrp(int pgrp, task_t *ignored_task)
+static int will_become_orphaned_pgrp(int pgrp, struct task_struct *ignored_task)
{
struct task_struct *p;
int ret = 1;
do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
if (p == ignored_task
|| p->exit_state
- || p->real_parent->pid == 1)
+ || is_init(p->real_parent))
continue;
if (process_group(p->real_parent) != pgrp
&& p->real_parent->signal->session == p->signal->session) {
do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
if (p->state != TASK_STOPPED)
continue;
-
- /* If p is stopped by a debugger on a signal that won't
- stop it, then don't count p as stopped. This isn't
- perfect but it's a good approximation. */
- if (unlikely (p->ptrace)
- && p->exit_code != SIGSTOP
- && p->exit_code != SIGTSTP
- && p->exit_code != SIGTTOU
- && p->exit_code != SIGTTIN)
- continue;
-
retval = 1;
break;
} while_each_task_pid(pgrp, PIDTYPE_PGID, p);
/* Set the exit signal to SIGCHLD so we signal init on exit */
current->exit_signal = SIGCHLD;
- if ((current->policy == SCHED_NORMAL ||
- current->policy == SCHED_BATCH)
- && (task_nice(current) < 0))
+ if (!has_rt_policy(current) && (task_nice(current) < 0))
set_user_nice(current, 0);
/* cpus_allowed? */
/* rt_priority? */
fs = init_task.fs;
current->fs = fs;
atomic_inc(&fs->count);
- exit_namespace(current);
- current->namespace = init_task.namespace;
- get_namespace(current->namespace);
+
+ exit_task_namespaces(current);
+ current->nsproxy = init_task.nsproxy;
+ get_task_namespaces(current);
+
exit_files(current);
current->files = init_task.files;
atomic_inc(¤t->files->count);
EXPORT_SYMBOL(put_files_struct);
+void reset_files_struct(struct task_struct *tsk, struct files_struct *files)
+{
+ struct files_struct *old;
+
+ old = tsk->files;
+ task_lock(tsk);
+ tsk->files = files;
+ task_unlock(tsk);
+ put_files_struct(old);
+}
+EXPORT_SYMBOL(reset_files_struct);
+
static inline void __exit_files(struct task_struct *tsk)
{
struct files_struct * files = tsk->files;
down_read(&mm->mmap_sem);
}
atomic_inc(&mm->mm_count);
- if (mm != tsk->active_mm) BUG();
+ BUG_ON(mm != tsk->active_mm);
/* more a memory barrier than a real lock */
task_lock(tsk);
tsk->mm = NULL;
mmput(mm);
}
-static inline void choose_new_parent(task_t *p, task_t *reaper)
+static inline void
+choose_new_parent(struct task_struct *p, struct task_struct *reaper)
{
/*
* Make sure we're not reparenting to ourselves and that
p->real_parent = reaper;
}
-static void reparent_thread(task_t *p, task_t *father, int traced)
+static void
+reparent_thread(struct task_struct *p, struct task_struct *father, int traced)
{
/* We don't want people slaying init. */
if (p->exit_signal != -1)
* anyway, so let go of it.
*/
p->ptrace = 0;
- list_del_init(&p->sibling);
+ remove_parent(p);
p->parent = p->real_parent;
- list_add_tail(&p->sibling, &p->parent->children);
+ add_parent(p);
/* If we'd notified the old parent about this child's death,
* also notify the new parent.
* group, and if no such member exists, give it to
* the global child reaper process (ie "init")
*/
-static void forget_original_parent(struct task_struct * father,
- struct list_head *to_release)
+static void
+forget_original_parent(struct task_struct *father, struct list_head *to_release)
{
struct task_struct *p, *reaper = father;
struct list_head *_p, *_n;
*/
list_for_each_safe(_p, _n, &father->children) {
int ptrace;
- p = list_entry(_p,struct task_struct,sibling);
+ p = list_entry(_p, struct task_struct, sibling);
ptrace = p->ptrace;
list_add(&p->ptrace_list, to_release);
}
list_for_each_safe(_p, _n, &father->ptrace_children) {
- p = list_entry(_p,struct task_struct,ptrace_list);
+ p = list_entry(_p, struct task_struct, ptrace_list);
choose_new_parent(p, reaper);
reparent_thread(p, father, 1);
}
list_for_each_safe(_p, _n, &ptrace_dead) {
list_del_init(_p);
- t = list_entry(_p,struct task_struct,ptrace_list);
+ t = list_entry(_p, struct task_struct, ptrace_list);
release_task(t);
}
fastcall NORET_TYPE void do_exit(long code)
{
struct task_struct *tsk = current;
+ struct taskstats *tidstats;
int group_dead;
+ unsigned int mycpu;
profile_task_exit(tsk);
tsk->flags |= PF_EXITING;
- /*
- * Make sure we don't try to process any timer firings
- * while we are already exiting.
- */
- tsk->it_virt_expires = cputime_zero;
- tsk->it_prof_expires = cputime_zero;
- tsk->it_sched_expires = 0;
-
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
current->comm, current->pid,
preempt_count());
+ taskstats_exit_alloc(&tidstats, &mycpu);
+
acct_update_integrals(tsk);
if (tsk->mm) {
update_hiwater_rss(tsk->mm);
if (group_dead) {
hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
- acct_process(code);
}
+ acct_collect(code, group_dead);
if (unlikely(tsk->robust_list))
exit_robust_list(tsk);
-#ifdef CONFIG_COMPAT
+#if defined(CONFIG_FUTEX) && defined(CONFIG_COMPAT)
if (unlikely(tsk->compat_robust_list))
compat_exit_robust_list(tsk);
#endif
+ if (unlikely(tsk->audit_context))
+ audit_free(tsk);
+ taskstats_exit_send(tsk, tidstats, group_dead, mycpu);
+ taskstats_exit_free(tidstats);
+
exit_mm(tsk);
+ if (group_dead)
+ acct_process();
exit_sem(tsk);
__exit_files(tsk);
__exit_fs(tsk);
- exit_namespace(tsk);
exit_thread();
cpuset_exit(tsk);
exit_keys(tsk);
tsk->exit_code = code;
proc_exit_connector(tsk);
exit_notify(tsk);
+ exit_task_namespaces(tsk);
#ifdef CONFIG_NUMA
mpol_free(tsk->mempolicy);
tsk->mempolicy = NULL;
#endif
/*
- * If DEBUG_MUTEXES is on, make sure we are holding no locks:
+ * This must happen late, after the PID is not
+ * hashed anymore:
+ */
+ if (unlikely(!list_empty(&tsk->pi_state_list)))
+ exit_pi_state_list(tsk);
+ if (unlikely(current->pi_state_cache))
+ kfree(current->pi_state_cache);
+ /*
+ * Make sure we are holding no locks:
*/
- mutex_debug_check_no_locks_held(tsk);
+ debug_check_no_locks_held(tsk);
if (tsk->io_context)
exit_io_context();
- /* PF_DEAD causes final put_task_struct after we schedule. */
+ if (tsk->splice_pipe)
+ __free_pipe_info(tsk->splice_pipe);
+
preempt_disable();
- BUG_ON(tsk->flags & PF_DEAD);
- tsk->flags |= PF_DEAD;
+ /* causes final put_task_struct in finish_task_switch(). */
+ tsk->state = TASK_DEAD;
schedule();
BUG();
/* Avoid "noreturn function does return". */
- for (;;) ;
+ for (;;)
+ cpu_relax(); /* For when BUG is null */
}
EXPORT_SYMBOL_GPL(do_exit);
{
if (comp)
complete(comp);
-
+
do_exit(code);
}
do_exit((error_code&0xff)<<8);
}
-task_t fastcall *next_thread(const task_t *p)
-{
- return pid_task(p->pids[PIDTYPE_TGID].pid_list.next, PIDTYPE_TGID);
-}
-
-EXPORT_SYMBOL(next_thread);
-
/*
* Take down every thread in the group. This is called by fatal signals
* as well as by sys_exit_group (below).
else if (!thread_group_empty(current)) {
struct signal_struct *const sig = current->signal;
struct sighand_struct *const sighand = current->sighand;
- read_lock(&tasklist_lock);
spin_lock_irq(&sighand->siglock);
if (sig->flags & SIGNAL_GROUP_EXIT)
/* Another thread got here before we took the lock. */
zap_other_threads(current);
}
spin_unlock_irq(&sighand->siglock);
- read_unlock(&tasklist_lock);
}
do_exit(exit_code);
do_group_exit((error_code & 0xff) << 8);
}
-static int eligible_child(pid_t pid, int options, task_t *p)
+static int eligible_child(pid_t pid, int options, struct task_struct *p)
{
if (pid > 0) {
if (p->pid != pid)
* Do not consider thread group leaders that are
* in a non-empty thread group:
*/
- if (current->tgid != p->tgid && delay_group_leader(p))
+ if (delay_group_leader(p))
return 2;
if (security_task_wait(p))
return 1;
}
-static int wait_noreap_copyout(task_t *p, pid_t pid, uid_t uid,
+static int wait_noreap_copyout(struct task_struct *p, pid_t pid, uid_t uid,
int why, int status,
struct siginfo __user *infop,
struct rusage __user *rusagep)
{
int retval = rusagep ? getrusage(p, RUSAGE_BOTH, rusagep) : 0;
+
put_task_struct(p);
if (!retval)
retval = put_user(SIGCHLD, &infop->si_signo);
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_zombie(task_t *p, int noreap,
+static int wait_task_zombie(struct task_struct *p, int noreap,
struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_stopped(task_t *p, int delayed_group_leader, int noreap,
- struct siginfo __user *infop,
+static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
+ int noreap, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
int retval, exit_code;
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_continued(task_t *p, int noreap,
+static int wait_task_continued(struct task_struct *p, int noreap,
struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
int ret;
list_for_each(_p,&tsk->children) {
- p = list_entry(_p,struct task_struct,sibling);
+ p = list_entry(_p, struct task_struct, sibling);
ret = eligible_child(pid, options, p);
if (!ret)
if (options & __WNOTHREAD)
break;
tsk = next_thread(tsk);
- if (tsk->signal != current->signal)
- BUG();
+ BUG_ON(tsk->signal != current->signal);
} while (tsk != current);
read_unlock(&tasklist_lock);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff