#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
-#include <linux/smp_lock.h>
#include <linux/module.h>
#include <linux/capability.h>
#include <linux/completion.h>
#include <linux/file.h>
#include <linux/binfmts.h>
#include <linux/nsproxy.h>
+#include <linux/pid_namespace.h>
#include <linux/ptrace.h>
#include <linux/profile.h>
#include <linux/mount.h>
#include <linux/proc_fs.h>
+#include <linux/kthread.h>
#include <linux/mempolicy.h>
#include <linux/taskstats_kern.h>
#include <linux/delayacct.h>
-#include <linux/cpuset.h>
+#include <linux/freezer.h>
+#include <linux/cgroup.h>
#include <linux/syscalls.h>
#include <linux/signal.h>
#include <linux/posix-timers.h>
#include <linux/audit.h> /* for audit_free() */
#include <linux/resource.h>
#include <linux/blkdev.h>
+#include <linux/task_io_accounting_ops.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
-extern void sem_exit (void);
-extern struct task_struct *child_reaper;
-
static void exit_mm(struct task_struct * tsk);
static void __unhash_process(struct task_struct *p)
* 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) {
+ 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);
/*
*/
sig->utime = cputime_add(sig->utime, tsk->utime);
sig->stime = cputime_add(sig->stime, tsk->stime);
+ sig->gtime = cputime_add(sig->gtime, tsk->gtime);
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->inblock += task_io_get_inblock(tsk);
+ sig->oublock += task_io_get_oublock(tsk);
+ sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
sig = NULL; /* Marker for below. */
}
int zap_leader;
repeat:
atomic_dec(&p->user->processes);
+ proc_flush_task(p);
write_lock_irq(&tasklist_lock);
ptrace_unlink(p);
BUG_ON(!list_empty(&p->ptrace_list) || !list_empty(&p->ptrace_children));
zap_leader = (leader->exit_signal == -1);
}
- sched_exit(p);
write_unlock_irq(&tasklist_lock);
- proc_flush_task(p);
release_thread(p);
call_rcu(&p->rcu, delayed_put_task_struct);
* 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
* without this...
+ *
+ * The caller must hold rcu lock or the tasklist lock.
*/
-int session_of_pgrp(int pgrp)
+struct pid *session_of_pgrp(struct pid *pgrp)
{
struct task_struct *p;
- int sid = -1;
+ struct pid *sid = NULL;
+
+ p = pid_task(pgrp, PIDTYPE_PGID);
+ if (p == NULL)
+ p = pid_task(pgrp, PIDTYPE_PID);
+ if (p != NULL)
+ sid = task_session(p);
- read_lock(&tasklist_lock);
- do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
- if (process_session(p) > 0) {
- sid = process_session(p);
- goto out;
- }
- } while_each_task_pid(pgrp, PIDTYPE_PGID, p);
- p = find_task_by_pid(pgrp);
- if (p)
- sid = process_session(p);
-out:
- read_unlock(&tasklist_lock);
-
return sid;
}
*
* "I ask you, have you ever known what it is to be an orphan?"
*/
-static int will_become_orphaned_pgrp(int pgrp, struct task_struct *ignored_task)
+static int will_become_orphaned_pgrp(struct pid *pgrp, struct task_struct *ignored_task)
{
struct task_struct *p;
int ret = 1;
- do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
+ do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
if (p == ignored_task
|| p->exit_state
- || is_init(p->real_parent))
+ || is_global_init(p->real_parent))
continue;
- if (process_group(p->real_parent) != pgrp &&
- process_session(p->real_parent) == process_session(p)) {
+ if (task_pgrp(p->real_parent) != pgrp &&
+ task_session(p->real_parent) == task_session(p)) {
ret = 0;
break;
}
- } while_each_task_pid(pgrp, PIDTYPE_PGID, p);
+ } while_each_pid_task(pgrp, PIDTYPE_PGID, p);
return ret; /* (sighing) "Often!" */
}
-int is_orphaned_pgrp(int pgrp)
+int is_current_pgrp_orphaned(void)
{
int retval;
read_lock(&tasklist_lock);
- retval = will_become_orphaned_pgrp(pgrp, NULL);
+ retval = will_become_orphaned_pgrp(task_pgrp(current), NULL);
read_unlock(&tasklist_lock);
return retval;
}
-static int has_stopped_jobs(int pgrp)
+static int has_stopped_jobs(struct pid *pgrp)
{
int retval = 0;
struct task_struct *p;
- do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
- if (p->state != TASK_STOPPED)
+ do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
+ if (!task_is_stopped(p))
continue;
retval = 1;
break;
- } while_each_task_pid(pgrp, PIDTYPE_PGID, p);
+ } while_each_pid_task(pgrp, PIDTYPE_PGID, p);
return retval;
}
/**
- * reparent_to_init - Reparent the calling kernel thread to the init task.
+ * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd
*
* If a kernel thread is launched as a result of a system call, or if
- * it ever exits, it should generally reparent itself to init so that
- * it is correctly cleaned up on exit.
+ * it ever exits, it should generally reparent itself to kthreadd so it
+ * isn't in the way of other processes and is correctly cleaned up on exit.
*
* The various task state such as scheduling policy and priority may have
* been inherited from a user process, so we reset them to sane values here.
*
- * NOTE that reparent_to_init() gives the caller full capabilities.
+ * NOTE that reparent_to_kthreadd() gives the caller full capabilities.
*/
-static void reparent_to_init(void)
+static void reparent_to_kthreadd(void)
{
write_lock_irq(&tasklist_lock);
ptrace_unlink(current);
/* Reparent to init */
remove_parent(current);
- current->parent = child_reaper;
- current->real_parent = child_reaper;
+ current->real_parent = current->parent = kthreadd_task;
add_parent(current);
/* Set the exit signal to SIGCHLD so we signal init on exit */
current->exit_signal = SIGCHLD;
- if (!has_rt_policy(current) && (task_nice(current) < 0))
+ if (task_nice(current) < 0)
set_user_nice(current, 0);
/* cpus_allowed? */
/* rt_priority? */
switch_uid(INIT_USER);
}
-void __set_special_pids(pid_t session, pid_t pgrp)
+void __set_special_pids(struct pid *pid)
{
struct task_struct *curr = current->group_leader;
+ pid_t nr = pid_nr(pid);
- if (process_session(curr) != session) {
+ if (task_session(curr) != pid) {
detach_pid(curr, PIDTYPE_SID);
- set_signal_session(curr->signal, session);
- attach_pid(curr, PIDTYPE_SID, session);
+ attach_pid(curr, PIDTYPE_SID, pid);
+ set_task_session(curr, nr);
}
- if (process_group(curr) != pgrp) {
+ if (task_pgrp(curr) != pid) {
detach_pid(curr, PIDTYPE_PGID);
- curr->signal->pgrp = pgrp;
- attach_pid(curr, PIDTYPE_PGID, pgrp);
+ attach_pid(curr, PIDTYPE_PGID, pid);
+ set_task_pgrp(curr, nr);
}
}
-static void set_special_pids(pid_t session, pid_t pgrp)
+static void set_special_pids(struct pid *pid)
{
write_lock_irq(&tasklist_lock);
- __set_special_pids(session, pgrp);
+ __set_special_pids(pid);
write_unlock_irq(&tasklist_lock);
}
return -EINVAL;
spin_lock_irq(¤t->sighand->siglock);
- sigaddset(¤t->blocked, sig);
+ current->sighand->action[(sig)-1].sa.sa_handler = SIG_IGN;
recalc_sigpending();
spin_unlock_irq(¤t->sighand->siglock);
return 0;
* they would be locked into memory.
*/
exit_mm(current);
+ /*
+ * We don't want to have TIF_FREEZE set if the system-wide hibernation
+ * or suspend transition begins right now.
+ */
+ current->flags |= PF_NOFREEZE;
- set_special_pids(1, 1);
+ if (current->nsproxy != &init_nsproxy) {
+ get_nsproxy(&init_nsproxy);
+ switch_task_namespaces(current, &init_nsproxy);
+ }
+ set_special_pids(&init_struct_pid);
proc_clear_tty(current);
/* Block and flush all signals */
current->fs = fs;
atomic_inc(&fs->count);
- exit_task_namespaces(current);
- current->nsproxy = init_task.nsproxy;
- get_task_namespaces(current);
-
- exit_files(current);
+ exit_files(current);
current->files = init_task.files;
atomic_inc(¤t->files->count);
- reparent_to_init();
+ reparent_to_kthreadd();
}
EXPORT_SYMBOL(daemonize);
for (;;) {
unsigned long set;
i = j * __NFDBITS;
- if (i >= fdt->max_fdset || i >= fdt->max_fds)
+ if (i >= fdt->max_fds)
break;
set = fdt->open_fds->fds_bits[j++];
while (set) {
if (set & 1) {
struct file * file = xchg(&fdt->fd[i], NULL);
- if (file)
+ if (file) {
filp_close(file, files);
+ cond_resched();
+ }
}
i++;
set >>= 1;
* you can free files immediately.
*/
fdt = files_fdtable(files);
- if (fdt == &files->fdtab)
- fdt->free_files = files;
- else
+ if (fdt != &files->fdtab)
kmem_cache_free(files_cachep, files);
free_fdtable(fdt);
}
}
EXPORT_SYMBOL(reset_files_struct);
-static inline void __exit_files(struct task_struct *tsk)
+static void __exit_files(struct task_struct *tsk)
{
struct files_struct * files = tsk->files;
__exit_files(tsk);
}
-static inline void __put_fs_struct(struct fs_struct *fs)
+static void __put_fs_struct(struct fs_struct *fs)
{
/* No need to hold fs->lock if we are killing it */
if (atomic_dec_and_test(&fs->count)) {
__put_fs_struct(fs);
}
-static inline void __exit_fs(struct task_struct *tsk)
+static void __exit_fs(struct task_struct *tsk)
{
struct fs_struct * fs = tsk->fs;
tsk->mm = NULL;
up_read(&mm->mmap_sem);
enter_lazy_tlb(mm, current);
+ /* We don't want this task to be frozen prematurely */
+ clear_freeze_flag(tsk);
task_unlock(tsk);
mmput(mm);
}
-static inline void
-choose_new_parent(struct task_struct *p, struct task_struct *reaper)
-{
- /*
- * Make sure we're not reparenting to ourselves and that
- * the parent is not a zombie.
- */
- BUG_ON(p == reaper || reaper->exit_state);
- p->real_parent = reaper;
-}
-
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)
- p->exit_signal = SIGCHLD;
-
if (p->pdeath_signal)
/* We already hold the tasklist_lock here. */
group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p);
p->parent = p->real_parent;
add_parent(p);
- /* If we'd notified the old parent about this child's death,
- * also notify the new parent.
- */
- if (p->exit_state == EXIT_ZOMBIE && p->exit_signal != -1 &&
- thread_group_empty(p))
- do_notify_parent(p, p->exit_signal);
- else if (p->state == TASK_TRACED) {
+ if (task_is_traced(p)) {
/*
* If it was at a trace stop, turn it into
* a normal stop since it's no longer being
}
}
+ /* If this is a threaded reparent there is no need to
+ * notify anyone anything has happened.
+ */
+ if (p->real_parent->group_leader == father->group_leader)
+ return;
+
+ /* We don't want people slaying init. */
+ if (p->exit_signal != -1)
+ p->exit_signal = SIGCHLD;
+
+ /* If we'd notified the old parent about this child's death,
+ * also notify the new parent.
+ */
+ if (!traced && p->exit_state == EXIT_ZOMBIE &&
+ p->exit_signal != -1 && thread_group_empty(p))
+ do_notify_parent(p, p->exit_signal);
+
/*
* process group orphan check
* Case ii: Our child is in a different pgrp
* than we are, and it was the only connection
* outside, so the child pgrp is now orphaned.
*/
- if ((process_group(p) != process_group(father)) &&
- (process_session(p) == process_session(father))) {
- int pgrp = process_group(p);
+ if ((task_pgrp(p) != task_pgrp(father)) &&
+ (task_session(p) == task_session(father))) {
+ struct pid *pgrp = task_pgrp(p);
if (will_become_orphaned_pgrp(pgrp, NULL) &&
has_stopped_jobs(pgrp)) {
- __kill_pg_info(SIGHUP, SEND_SIG_PRIV, pgrp);
- __kill_pg_info(SIGCONT, SEND_SIG_PRIV, pgrp);
+ __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp);
+ __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp);
}
}
}
* When we die, we re-parent all our children.
* Try to give them to another thread in our thread
* group, and if no such member exists, give it to
- * the global child reaper process (ie "init")
+ * the child reaper process (ie "init") in our pid
+ * space.
*/
-static void
-forget_original_parent(struct task_struct *father, struct list_head *to_release)
+static void forget_original_parent(struct task_struct *father)
{
- struct task_struct *p, *reaper = father;
- struct list_head *_p, *_n;
+ struct task_struct *p, *n, *reaper = father;
+ struct list_head ptrace_dead;
+
+ INIT_LIST_HEAD(&ptrace_dead);
+
+ write_lock_irq(&tasklist_lock);
do {
reaper = next_thread(reaper);
if (reaper == father) {
- reaper = child_reaper;
+ reaper = task_child_reaper(father);
break;
}
- } while (reaper->exit_state);
+ } while (reaper->flags & PF_EXITING);
/*
* There are only two places where our children can be:
*
* Search them and reparent children.
*/
- list_for_each_safe(_p, _n, &father->children) {
+ list_for_each_entry_safe(p, n, &father->children, sibling) {
int ptrace;
- p = list_entry(_p, struct task_struct, sibling);
ptrace = p->ptrace;
if (father == p->real_parent) {
/* reparent with a reaper, real father it's us */
- choose_new_parent(p, reaper);
+ p->real_parent = reaper;
reparent_thread(p, father, 0);
} else {
/* reparent ptraced task to its real parent */
* while it was being traced by us, to be able to see it in wait4.
*/
if (unlikely(ptrace && p->exit_state == EXIT_ZOMBIE && p->exit_signal == -1))
- list_add(&p->ptrace_list, to_release);
+ list_add(&p->ptrace_list, &ptrace_dead);
}
- list_for_each_safe(_p, _n, &father->ptrace_children) {
- p = list_entry(_p, struct task_struct, ptrace_list);
- choose_new_parent(p, reaper);
+
+ list_for_each_entry_safe(p, n, &father->ptrace_children, ptrace_list) {
+ p->real_parent = reaper;
reparent_thread(p, father, 1);
}
+
+ write_unlock_irq(&tasklist_lock);
+ BUG_ON(!list_empty(&father->children));
+ BUG_ON(!list_empty(&father->ptrace_children));
+
+ list_for_each_entry_safe(p, n, &ptrace_dead, ptrace_list) {
+ list_del_init(&p->ptrace_list);
+ release_task(p);
+ }
+
}
/*
{
int state;
struct task_struct *t;
- struct list_head ptrace_dead, *_p, *_n;
-
- if (signal_pending(tsk) && !(tsk->signal->flags & SIGNAL_GROUP_EXIT)
- && !thread_group_empty(tsk)) {
- /*
- * This occurs when there was a race between our exit
- * syscall and a group signal choosing us as the one to
- * wake up. It could be that we are the only thread
- * alerted to check for pending signals, but another thread
- * should be woken now to take the signal since we will not.
- * Now we'll wake all the threads in the group just to make
- * sure someone gets all the pending signals.
- */
- read_lock(&tasklist_lock);
- spin_lock_irq(&tsk->sighand->siglock);
- for (t = next_thread(tsk); t != tsk; t = next_thread(t))
- if (!signal_pending(t) && !(t->flags & PF_EXITING)) {
- recalc_sigpending_tsk(t);
- if (signal_pending(t))
- signal_wake_up(t, 0);
- }
- spin_unlock_irq(&tsk->sighand->siglock);
- read_unlock(&tasklist_lock);
- }
-
- write_lock_irq(&tasklist_lock);
+ struct pid *pgrp;
/*
* This does two things:
* as a result of our exiting, and if they have any stopped
* jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2)
*/
+ forget_original_parent(tsk);
+ exit_task_namespaces(tsk);
- INIT_LIST_HEAD(&ptrace_dead);
- forget_original_parent(tsk, &ptrace_dead);
- BUG_ON(!list_empty(&tsk->children));
- BUG_ON(!list_empty(&tsk->ptrace_children));
-
+ write_lock_irq(&tasklist_lock);
/*
* Check to see if any process groups have become orphaned
* as a result of our exiting, and if they have any stopped
* and we were the only connection outside, so our pgrp
* is about to become orphaned.
*/
-
t = tsk->real_parent;
-
- if ((process_group(t) != process_group(tsk)) &&
- (process_session(t) == process_session(tsk)) &&
- will_become_orphaned_pgrp(process_group(tsk), tsk) &&
- has_stopped_jobs(process_group(tsk))) {
- __kill_pg_info(SIGHUP, SEND_SIG_PRIV, process_group(tsk));
- __kill_pg_info(SIGCONT, SEND_SIG_PRIV, process_group(tsk));
+
+ pgrp = task_pgrp(tsk);
+ if ((task_pgrp(t) != pgrp) &&
+ (task_session(t) == task_session(tsk)) &&
+ will_become_orphaned_pgrp(pgrp, tsk) &&
+ has_stopped_jobs(pgrp)) {
+ __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp);
+ __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp);
}
- /* Let father know we died
+ /* Let father know we died
*
* Thread signals are configurable, but you aren't going to use
- * that to send signals to arbitary processes.
+ * that to send signals to arbitary processes.
* That stops right now.
*
* If the parent exec id doesn't match the exec id we saved
* If our self_exec id doesn't match our parent_exec_id then
* we have changed execution domain as these two values started
* the same after a fork.
- *
*/
-
if (tsk->exit_signal != SIGCHLD && tsk->exit_signal != -1 &&
( tsk->parent_exec_id != t->self_exec_id ||
tsk->self_exec_id != tsk->parent_exec_id)
}
state = EXIT_ZOMBIE;
- if (tsk->exit_signal == -1 &&
- (likely(tsk->ptrace == 0) ||
- unlikely(tsk->parent->signal->flags & SIGNAL_GROUP_EXIT)))
+ if (tsk->exit_signal == -1 && likely(!tsk->ptrace))
state = EXIT_DEAD;
tsk->exit_state = state;
- write_unlock_irq(&tasklist_lock);
+ if (thread_group_leader(tsk) &&
+ tsk->signal->notify_count < 0 &&
+ tsk->signal->group_exit_task)
+ wake_up_process(tsk->signal->group_exit_task);
- list_for_each_safe(_p, _n, &ptrace_dead) {
- list_del_init(_p);
- t = list_entry(_p, struct task_struct, ptrace_list);
- release_task(t);
- }
+ write_unlock_irq(&tasklist_lock);
/* If the process is dead, release it - nobody will wait for it */
if (state == EXIT_DEAD)
release_task(tsk);
}
+#ifdef CONFIG_DEBUG_STACK_USAGE
+static void check_stack_usage(void)
+{
+ static DEFINE_SPINLOCK(low_water_lock);
+ static int lowest_to_date = THREAD_SIZE;
+ unsigned long *n = end_of_stack(current);
+ unsigned long free;
+
+ while (*n == 0)
+ n++;
+ free = (unsigned long)n - (unsigned long)end_of_stack(current);
+
+ if (free >= lowest_to_date)
+ return;
+
+ spin_lock(&low_water_lock);
+ if (free < lowest_to_date) {
+ printk(KERN_WARNING "%s used greatest stack depth: %lu bytes "
+ "left\n",
+ current->comm, free);
+ lowest_to_date = free;
+ }
+ spin_unlock(&low_water_lock);
+}
+#else
+static inline void check_stack_usage(void) {}
+#endif
+
+static inline void exit_child_reaper(struct task_struct *tsk)
+{
+ if (likely(tsk->group_leader != task_child_reaper(tsk)))
+ return;
+
+ if (tsk->nsproxy->pid_ns == &init_pid_ns)
+ panic("Attempted to kill init!");
+
+ /*
+ * @tsk is the last thread in the 'cgroup-init' and is exiting.
+ * Terminate all remaining processes in the namespace and reap them
+ * before exiting @tsk.
+ *
+ * Note that @tsk (last thread of cgroup-init) may not necessarily
+ * be the child-reaper (i.e main thread of cgroup-init) of the
+ * namespace i.e the child_reaper may have already exited.
+ *
+ * Even after a child_reaper exits, we let it inherit orphaned children,
+ * because, pid_ns->child_reaper remains valid as long as there is
+ * at least one living sub-thread in the cgroup init.
+
+ * This living sub-thread of the cgroup-init will be notified when
+ * a child inherited by the 'child-reaper' exits (do_notify_parent()
+ * uses __group_send_sig_info()). Further, when reaping child processes,
+ * do_wait() iterates over children of all living sub threads.
+
+ * i.e even though 'child_reaper' thread is listed as the parent of the
+ * orphaned children, any living sub-thread in the cgroup-init can
+ * perform the role of the child_reaper.
+ */
+ zap_pid_ns_processes(tsk->nsproxy->pid_ns);
+}
+
fastcall NORET_TYPE void do_exit(long code)
{
struct task_struct *tsk = current;
panic("Aiee, killing interrupt handler!");
if (unlikely(!tsk->pid))
panic("Attempted to kill the idle task!");
- if (unlikely(tsk == child_reaper))
- panic("Attempted to kill init!");
if (unlikely(current->ptrace & PT_TRACE_EXIT)) {
current->ptrace_message = code;
if (unlikely(tsk->flags & PF_EXITING)) {
printk(KERN_ALERT
"Fixing recursive fault but reboot is needed!\n");
+ /*
+ * We can do this unlocked here. The futex code uses
+ * this flag just to verify whether the pi state
+ * cleanup has been done or not. In the worst case it
+ * loops once more. We pretend that the cleanup was
+ * done as there is no way to return. Either the
+ * OWNER_DIED bit is set by now or we push the blocked
+ * task into the wait for ever nirwana as well.
+ */
+ tsk->flags |= PF_EXITPIDONE;
if (tsk->io_context)
exit_io_context();
set_current_state(TASK_UNINTERRUPTIBLE);
schedule();
}
- tsk->flags |= PF_EXITING;
+ exit_signals(tsk); /* sets PF_EXITING */
+ /*
+ * tsk->flags are checked in the futex code to protect against
+ * an exiting task cleaning up the robust pi futexes.
+ */
+ smp_mb();
+ spin_unlock_wait(&tsk->pi_lock);
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
- current->comm, current->pid,
+ current->comm, task_pid_nr(current),
preempt_count());
acct_update_integrals(tsk);
}
group_dead = atomic_dec_and_test(&tsk->signal->live);
if (group_dead) {
- hrtimer_cancel(&tsk->signal->real_timer);
+ exit_child_reaper(tsk);
+ hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
}
acct_collect(code, group_dead);
+#ifdef CONFIG_FUTEX
if (unlikely(tsk->robust_list))
exit_robust_list(tsk);
-#if defined(CONFIG_FUTEX) && defined(CONFIG_COMPAT)
+#ifdef CONFIG_COMPAT
if (unlikely(tsk->compat_robust_list))
compat_exit_robust_list(tsk);
#endif
+#endif
+ if (group_dead)
+ tty_audit_exit();
if (unlikely(tsk->audit_context))
audit_free(tsk);
+ tsk->exit_code = code;
taskstats_exit(tsk, group_dead);
exit_mm(tsk);
exit_sem(tsk);
__exit_files(tsk);
__exit_fs(tsk);
+ check_stack_usage();
exit_thread();
- cpuset_exit(tsk);
+ cgroup_exit(tsk, 1);
exit_keys(tsk);
if (group_dead && tsk->signal->leader)
if (tsk->binfmt)
module_put(tsk->binfmt->module);
- 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
+#ifdef CONFIG_FUTEX
/*
* This must happen late, after the PID is not
* hashed anymore:
exit_pi_state_list(tsk);
if (unlikely(current->pi_state_cache))
kfree(current->pi_state_cache);
+#endif
/*
* Make sure we are holding no locks:
*/
debug_check_no_locks_held(tsk);
+ /*
+ * We can do this unlocked here. The futex code uses this flag
+ * just to verify whether the pi state cleanup has been done
+ * or not. In the worst case it loops once more.
+ */
+ tsk->flags |= PF_EXITPIDONE;
if (tsk->io_context)
exit_io_context();
struct signal_struct *const sig = current->signal;
struct sighand_struct *const sighand = current->sighand;
spin_lock_irq(&sighand->siglock);
- if (sig->flags & SIGNAL_GROUP_EXIT)
+ if (signal_group_exit(sig))
/* Another thread got here before we took the lock. */
exit_code = sig->group_exit_code;
else {
sig->group_exit_code = exit_code;
+ sig->flags = SIGNAL_GROUP_EXIT;
zap_other_threads(current);
}
spin_unlock_irq(&sighand->siglock);
static int eligible_child(pid_t pid, int options, struct task_struct *p)
{
+ int err;
+ struct pid_namespace *ns;
+
+ ns = current->nsproxy->pid_ns;
if (pid > 0) {
- if (p->pid != pid)
+ if (task_pid_nr_ns(p, ns) != pid)
return 0;
} else if (!pid) {
- if (process_group(p) != process_group(current))
+ if (task_pgrp_nr_ns(p, ns) != task_pgrp_vnr(current))
return 0;
} else if (pid != -1) {
- if (process_group(p) != -pid)
+ if (task_pgrp_nr_ns(p, ns) != -pid)
return 0;
}
if (((p->exit_signal != SIGCHLD) ^ ((options & __WCLONE) != 0))
&& !(options & __WALL))
return 0;
- /*
- * Do not consider thread group leaders that are
- * in a non-empty thread group:
- */
- if (delay_group_leader(p))
- return 2;
- if (security_task_wait(p))
- return 0;
+ err = security_task_wait(p);
+ if (likely(!err))
+ return 1;
- return 1;
+ if (pid <= 0)
+ return 0;
+ /* This child was explicitly requested, abort */
+ read_unlock(&tasklist_lock);
+ return err;
}
static int wait_noreap_copyout(struct task_struct *p, pid_t pid, uid_t uid,
int __user *stat_addr, struct rusage __user *ru)
{
unsigned long state;
- int retval;
- int status;
+ int retval, status, traced;
+ pid_t pid = task_pid_nr_ns(p, current->nsproxy->pid_ns);
if (unlikely(noreap)) {
- pid_t pid = p->pid;
uid_t uid = p->uid;
int exit_code = p->exit_code;
int why, status;
- if (unlikely(p->exit_state != EXIT_ZOMBIE))
- return 0;
- if (unlikely(p->exit_signal == -1 && p->ptrace == 0))
- return 0;
get_task_struct(p);
read_unlock(&tasklist_lock);
if ((exit_code & 0x7f) == 0) {
BUG_ON(state != EXIT_DEAD);
return 0;
}
- if (unlikely(p->exit_signal == -1 && p->ptrace == 0)) {
- /*
- * This can only happen in a race with a ptraced thread
- * dying on another processor.
- */
- return 0;
- }
- if (likely(p->real_parent == p->parent) && likely(p->signal)) {
+ /* traced means p->ptrace, but not vice versa */
+ traced = (p->real_parent != p->parent);
+
+ if (likely(!traced)) {
struct signal_struct *psig;
struct signal_struct *sig;
cputime_add(p->stime,
cputime_add(sig->stime,
sig->cstime)));
+ psig->cgtime =
+ cputime_add(psig->cgtime,
+ cputime_add(p->gtime,
+ cputime_add(sig->gtime,
+ sig->cgtime)));
psig->cmin_flt +=
p->min_flt + sig->min_flt + sig->cmin_flt;
psig->cmaj_flt +=
p->nvcsw + sig->nvcsw + sig->cnvcsw;
psig->cnivcsw +=
p->nivcsw + sig->nivcsw + sig->cnivcsw;
+ psig->cinblock +=
+ task_io_get_inblock(p) +
+ sig->inblock + sig->cinblock;
+ psig->coublock +=
+ task_io_get_oublock(p) +
+ sig->oublock + sig->coublock;
spin_unlock_irq(&p->parent->sighand->siglock);
}
retval = put_user(status, &infop->si_status);
}
if (!retval && infop)
- retval = put_user(p->pid, &infop->si_pid);
+ retval = put_user(pid, &infop->si_pid);
if (!retval && infop)
retval = put_user(p->uid, &infop->si_uid);
- if (retval) {
- // TODO: is this safe?
- p->exit_state = EXIT_ZOMBIE;
- return retval;
- }
- retval = p->pid;
- if (p->real_parent != p->parent) {
+ if (!retval)
+ retval = pid;
+
+ if (traced) {
write_lock_irq(&tasklist_lock);
- /* Double-check with lock held. */
- if (p->real_parent != p->parent) {
- __ptrace_unlink(p);
- // TODO: is this safe?
- p->exit_state = EXIT_ZOMBIE;
- /*
- * If this is not a detached task, notify the parent.
- * If it's still not detached after that, don't release
- * it now.
- */
+ /* We dropped tasklist, ptracer could die and untrace */
+ ptrace_unlink(p);
+ /*
+ * If this is not a detached task, notify the parent.
+ * If it's still not detached after that, don't release
+ * it now.
+ */
+ if (p->exit_signal != -1) {
+ do_notify_parent(p, p->exit_signal);
if (p->exit_signal != -1) {
- do_notify_parent(p, p->exit_signal);
- if (p->exit_signal != -1)
- p = NULL;
+ p->exit_state = EXIT_ZOMBIE;
+ p = NULL;
}
}
write_unlock_irq(&tasklist_lock);
}
if (p != NULL)
release_task(p);
- BUG_ON(!retval);
+
return retval;
}
* 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(struct task_struct *p, int delayed_group_leader,
+static int wait_task_stopped(struct task_struct *p,
int noreap, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
- int retval, exit_code;
+ int retval, exit_code, why;
+ uid_t uid = 0; /* unneeded, required by compiler */
+ pid_t pid;
- if (!p->exit_code)
- return 0;
- if (delayed_group_leader && !(p->ptrace & PT_PTRACED) &&
- p->signal && p->signal->group_stop_count > 0)
+ exit_code = 0;
+ spin_lock_irq(&p->sighand->siglock);
+
+ if (unlikely(!task_is_stopped_or_traced(p)))
+ goto unlock_sig;
+
+ if (!(p->ptrace & PT_PTRACED) && p->signal->group_stop_count > 0)
/*
* A group stop is in progress and this is the group leader.
* We won't report until all threads have stopped.
*/
+ goto unlock_sig;
+
+ exit_code = p->exit_code;
+ if (!exit_code)
+ goto unlock_sig;
+
+ if (!noreap)
+ p->exit_code = 0;
+
+ uid = p->uid;
+unlock_sig:
+ spin_unlock_irq(&p->sighand->siglock);
+ if (!exit_code)
return 0;
/*
* possibly take page faults for user memory.
*/
get_task_struct(p);
+ pid = task_pid_nr_ns(p, current->nsproxy->pid_ns);
+ why = (p->ptrace & PT_PTRACED) ? CLD_TRAPPED : CLD_STOPPED;
read_unlock(&tasklist_lock);
- if (unlikely(noreap)) {
- pid_t pid = p->pid;
- uid_t uid = p->uid;
- int why = (p->ptrace & PT_PTRACED) ? CLD_TRAPPED : CLD_STOPPED;
-
- exit_code = p->exit_code;
- if (unlikely(!exit_code) ||
- unlikely(p->state & TASK_TRACED))
- goto bail_ref;
+ if (unlikely(noreap))
return wait_noreap_copyout(p, pid, uid,
- why, (exit_code << 8) | 0x7f,
+ why, exit_code,
infop, ru);
- }
-
- write_lock_irq(&tasklist_lock);
-
- /*
- * This uses xchg to be atomic with the thread resuming and setting
- * it. It must also be done with the write lock held to prevent a
- * race with the EXIT_ZOMBIE case.
- */
- exit_code = xchg(&p->exit_code, 0);
- if (unlikely(p->exit_state)) {
- /*
- * The task resumed and then died. Let the next iteration
- * catch it in EXIT_ZOMBIE. Note that exit_code might
- * already be zero here if it resumed and did _exit(0).
- * The task itself is dead and won't touch exit_code again;
- * other processors in this function are locked out.
- */
- p->exit_code = exit_code;
- exit_code = 0;
- }
- if (unlikely(exit_code == 0)) {
- /*
- * Another thread in this function got to it first, or it
- * resumed, or it resumed and then died.
- */
- write_unlock_irq(&tasklist_lock);
-bail_ref:
- put_task_struct(p);
- /*
- * We are returning to the wait loop without having successfully
- * removed the process and having released the lock. We cannot
- * continue, since the "p" task pointer is potentially stale.
- *
- * Return -EAGAIN, and do_wait() will restart the loop from the
- * beginning. Do _not_ re-acquire the lock.
- */
- return -EAGAIN;
- }
-
- /* move to end of parent's list to avoid starvation */
- remove_parent(p);
- add_parent(p);
-
- write_unlock_irq(&tasklist_lock);
retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
if (!retval && stat_addr)
if (!retval && infop)
retval = put_user(0, &infop->si_errno);
if (!retval && infop)
- retval = put_user((short)((p->ptrace & PT_PTRACED)
- ? CLD_TRAPPED : CLD_STOPPED),
- &infop->si_code);
+ retval = put_user(why, &infop->si_code);
if (!retval && infop)
retval = put_user(exit_code, &infop->si_status);
if (!retval && infop)
- retval = put_user(p->pid, &infop->si_pid);
+ retval = put_user(pid, &infop->si_pid);
if (!retval && infop)
- retval = put_user(p->uid, &infop->si_uid);
+ retval = put_user(uid, &infop->si_uid);
if (!retval)
- retval = p->pid;
+ retval = pid;
put_task_struct(p);
BUG_ON(!retval);
pid_t pid;
uid_t uid;
- if (unlikely(!p->signal))
- return 0;
-
if (!(p->signal->flags & SIGNAL_STOP_CONTINUED))
return 0;
p->signal->flags &= ~SIGNAL_STOP_CONTINUED;
spin_unlock_irq(&p->sighand->siglock);
- pid = p->pid;
+ pid = task_pid_nr_ns(p, current->nsproxy->pid_ns);
uid = p->uid;
get_task_struct(p);
read_unlock(&tasklist_lock);
if (!retval && stat_addr)
retval = put_user(0xffff, stat_addr);
if (!retval)
- retval = p->pid;
+ retval = pid;
} else {
retval = wait_noreap_copyout(p, pid, uid,
CLD_CONTINUED, SIGCONT,
return retval;
}
-
-static inline int my_ptrace_child(struct task_struct *p)
-{
- if (!(p->ptrace & PT_PTRACED))
- return 0;
- if (!(p->ptrace & PT_ATTACHED))
- return 1;
- /*
- * This child was PTRACE_ATTACH'd. We should be seeing it only if
- * we are the attacher. If we are the real parent, this is a race
- * inside ptrace_attach. It is waiting for the tasklist_lock,
- * which we have to switch the parent links, but has already set
- * the flags in p->ptrace.
- */
- return (p->parent != p->real_parent);
-}
-
static long do_wait(pid_t pid, int options, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
* We will set this flag if we see any child that might later
* match our criteria, even if we are not able to reap it yet.
*/
- flag = 0;
+ flag = retval = 0;
current->state = TASK_INTERRUPTIBLE;
read_lock(&tasklist_lock);
tsk = current;
do {
struct task_struct *p;
- struct list_head *_p;
- int ret;
- list_for_each(_p,&tsk->children) {
- p = list_entry(_p, struct task_struct, sibling);
-
- ret = eligible_child(pid, options, p);
+ list_for_each_entry(p, &tsk->children, sibling) {
+ int ret = eligible_child(pid, options, p);
if (!ret)
continue;
- switch (p->state) {
- case TASK_TRACED:
- /*
- * When we hit the race with PTRACE_ATTACH,
- * we will not report this child. But the
- * race means it has not yet been moved to
- * our ptrace_children list, so we need to
- * set the flag here to avoid a spurious ECHILD
- * when the race happens with the only child.
- */
- flag = 1;
- if (!my_ptrace_child(p))
- continue;
- /*FALLTHROUGH*/
- case TASK_STOPPED:
+ if (unlikely(ret < 0)) {
+ retval = ret;
+ } else if (task_is_stopped_or_traced(p)) {
/*
* It's stopped now, so it might later
* continue, exit, or stop again.
*/
flag = 1;
- if (!(options & WUNTRACED) &&
- !my_ptrace_child(p))
+ if (!(p->ptrace & PT_PTRACED) &&
+ !(options & WUNTRACED))
continue;
- retval = wait_task_stopped(p, ret == 2,
- (options & WNOWAIT),
- infop,
- stat_addr, ru);
- if (retval == -EAGAIN)
- goto repeat;
- if (retval != 0) /* He released the lock. */
- goto end;
- break;
- default:
- // case EXIT_DEAD:
- if (p->exit_state == EXIT_DEAD)
+
+ retval = wait_task_stopped(p,
+ (options & WNOWAIT), infop,
+ stat_addr, ru);
+ } else if (p->exit_state == EXIT_ZOMBIE &&
+ !delay_group_leader(p)) {
+ /*
+ * We don't reap group leaders with subthreads.
+ */
+ if (!likely(options & WEXITED))
continue;
- // case EXIT_ZOMBIE:
- if (p->exit_state == EXIT_ZOMBIE) {
- /*
- * Eligible but we cannot release
- * it yet:
- */
- if (ret == 2)
- goto check_continued;
- if (!likely(options & WEXITED))
- continue;
- retval = wait_task_zombie(
- p, (options & WNOWAIT),
- infop, stat_addr, ru);
- /* He released the lock. */
- if (retval != 0)
- goto end;
- break;
- }
-check_continued:
+ retval = wait_task_zombie(p,
+ (options & WNOWAIT), infop,
+ stat_addr, ru);
+ } else if (p->exit_state != EXIT_DEAD) {
/*
* It's running now, so it might later
* exit, stop, or stop and then continue.
flag = 1;
if (!unlikely(options & WCONTINUED))
continue;
- retval = wait_task_continued(
- p, (options & WNOWAIT),
- infop, stat_addr, ru);
- if (retval != 0) /* He released the lock. */
- goto end;
- break;
+ retval = wait_task_continued(p,
+ (options & WNOWAIT), infop,
+ stat_addr, ru);
}
+ if (retval != 0) /* tasklist_lock released */
+ goto end;
}
if (!flag) {
- list_for_each(_p, &tsk->ptrace_children) {
- p = list_entry(_p, struct task_struct,
- ptrace_list);
- if (!eligible_child(pid, options, p))
+ list_for_each_entry(p, &tsk->ptrace_children,
+ ptrace_list) {
+ flag = eligible_child(pid, options, p);
+ if (!flag)
continue;
- flag = 1;
- break;
+ if (likely(flag > 0))
+ break;
+ retval = flag;
+ goto end;
}
}
if (options & __WNOTHREAD)
tsk = next_thread(tsk);
BUG_ON(tsk->signal != current->signal);
} while (tsk != current);
-
read_unlock(&tasklist_lock);
+
if (flag) {
- retval = 0;
if (options & WNOHANG)
goto end;
retval = -ERESTARTSYS;
remove_wait_queue(¤t->signal->wait_chldexit,&wait);
if (infop) {
if (retval > 0)
- retval = 0;
+ retval = 0;
else {
/*
* For a WNOHANG return, clear out all the fields
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff