#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 <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);
- 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);
+}
- REMOVE_LINKS(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)
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
spin_unlock(&p->proc_lock);
proc_pid_flush(proc_dentry);
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
ptrace_unlink(current);
/* Reparent to init */
- REMOVE_LINKS(current);
+ remove_parent(current);
current->parent = child_reaper;
current->real_parent = child_reaper;
- SET_LINKS(current);
+ add_parent(current);
/* Set the exit signal to SIGCHLD so we signal init on exit */
current->exit_signal = SIGCHLD;
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, task_t *child_reaper)
+static inline void choose_new_parent(task_t *p, task_t *reaper)
{
/*
* Make sure we're not reparenting to ourselves and that
* the parent is not a zombie.
*/
- BUG_ON(p == reaper || reaper->exit_state >= EXIT_ZOMBIE);
+ BUG_ON(p == reaper || reaper->exit_state);
p->real_parent = reaper;
}
* 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.
if (father == p->real_parent) {
/* reparent with a reaper, real father it's us */
- choose_new_parent(p, reaper, child_reaper);
+ choose_new_parent(p, reaper);
reparent_thread(p, father, 0);
} else {
/* reparent ptraced task to its real parent */
}
list_for_each_safe(_p, _n, &father->ptrace_children) {
p = list_entry(_p,struct task_struct,ptrace_list);
- choose_new_parent(p, reaper, child_reaper);
+ choose_new_parent(p, reaper);
reparent_thread(p, father, 1);
}
}
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,
if (unlikely(tsk->compat_robust_list))
compat_exit_robust_list(tsk);
#endif
+ if (unlikely(tsk->audit_context))
+ audit_free(tsk);
exit_mm(tsk);
exit_sem(tsk);
if (tsk->io_context)
exit_io_context();
+ if (tsk->splice_pipe)
+ __free_pipe_info(tsk->splice_pipe);
+
/* PF_DEAD causes final put_task_struct after we schedule. */
preempt_disable();
BUG_ON(tsk->flags & PF_DEAD);
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);
/* move to end of parent's list to avoid starvation */
remove_parent(p);
- add_parent(p, p->parent);
+ add_parent(p);
write_unlock_irq(&tasklist_lock);
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);
Code Review / linux-2.6.git / blobdiff