Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/kernel/exit.c b/kernel/exit.c
new file mode 100644
index 0000000..6dd4ebe
--- /dev/null
+++ b/kernel/exit.c
@@ -0,0 +1,1527 @@
+/*
+ * linux/kernel/exit.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/config.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/smp_lock.h>
+#include <linux/module.h>
+#include <linux/completion.h>
+#include <linux/personality.h>
+#include <linux/tty.h>
+#include <linux/namespace.h>
+#include <linux/key.h>
+#include <linux/security.h>
+#include <linux/cpu.h>
+#include <linux/acct.h>
+#include <linux/file.h>
+#include <linux/binfmts.h>
+#include <linux/ptrace.h>
+#include <linux/profile.h>
+#include <linux/mount.h>
+#include <linux/proc_fs.h>
+#include <linux/mempolicy.h>
+#include <linux/cpuset.h>
+#include <linux/syscalls.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;
+
+int getrusage(struct task_struct *, int, struct rusage __user *);
+
+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)--;
+ }
+
+ REMOVE_LINKS(p);
+}
+
+void release_task(struct task_struct * p)
+{
+ int zap_leader;
+ task_t *leader;
+ struct dentry *proc_dentry;
+
+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);
+ BUG_ON(!list_empty(&p->ptrace_list) || !list_empty(&p->ptrace_children));
+ __exit_signal(p);
+ __exit_sighand(p);
+ __unhash_process(p);
+
+ /*
+ * If we are the last non-leader member of the thread
+ * group, and the leader is zombie, then notify the
+ * group leader's parent process. (if it wants notification.)
+ */
+ zap_leader = 0;
+ leader = p->group_leader;
+ if (leader != p && thread_group_empty(leader) && leader->exit_state == EXIT_ZOMBIE) {
+ BUG_ON(leader->exit_signal == -1);
+ do_notify_parent(leader, leader->exit_signal);
+ /*
+ * If we were the last child thread and the leader has
+ * exited already, and the leader's parent ignores SIGCHLD,
+ * then we are the one who should release the leader.
+ *
+ * do_notify_parent() will have marked it self-reaping in
+ * that case.
+ */
+ zap_leader = (leader->exit_signal == -1);
+ }
+
+ sched_exit(p);
+ write_unlock_irq(&tasklist_lock);
+ spin_unlock(&p->proc_lock);
+ proc_pid_flush(proc_dentry);
+ release_thread(p);
+ put_task_struct(p);
+
+ 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
+ * without this...
+ */
+int session_of_pgrp(int pgrp)
+{
+ struct task_struct *p;
+ int sid = -1;
+
+ read_lock(&tasklist_lock);
+ do_each_task_pid(pgrp, PIDTYPE_PGID, p) {
+ if (p->signal->session > 0) {
+ sid = p->signal->session;
+ goto out;
+ }
+ } while_each_task_pid(pgrp, PIDTYPE_PGID, p);
+ p = find_task_by_pid(pgrp);
+ if (p)
+ sid = p->signal->session;
+out:
+ read_unlock(&tasklist_lock);
+
+ return sid;
+}
+
+/*
+ * Determine if a process group is "orphaned", according to the POSIX
+ * definition in 2.2.2.52. Orphaned process groups are not to be affected
+ * by terminal-generated stop signals. Newly orphaned process groups are
+ * to receive a SIGHUP and a SIGCONT.
+ *
+ * "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)
+{
+ 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)
+ continue;
+ if (process_group(p->real_parent) != pgrp
+ && p->real_parent->signal->session == p->signal->session) {
+ ret = 0;
+ break;
+ }
+ } while_each_task_pid(pgrp, PIDTYPE_PGID, p);
+ return ret; /* (sighing) "Often!" */
+}
+
+int is_orphaned_pgrp(int pgrp)
+{
+ int retval;
+
+ read_lock(&tasklist_lock);
+ retval = will_become_orphaned_pgrp(pgrp, NULL);
+ read_unlock(&tasklist_lock);
+
+ return retval;
+}
+
+static inline int has_stopped_jobs(int pgrp)
+{
+ int retval = 0;
+ struct task_struct *p;
+
+ 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);
+ return retval;
+}
+
+/**
+ * reparent_to_init() - Reparent the calling kernel thread to the init task.
+ *
+ * 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.
+ *
+ * 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.
+ */
+void reparent_to_init(void)
+{
+ write_lock_irq(&tasklist_lock);
+
+ ptrace_unlink(current);
+ /* Reparent to init */
+ REMOVE_LINKS(current);
+ current->parent = child_reaper;
+ current->real_parent = child_reaper;
+ SET_LINKS(current);
+
+ /* Set the exit signal to SIGCHLD so we signal init on exit */
+ current->exit_signal = SIGCHLD;
+
+ if ((current->policy == SCHED_NORMAL) && (task_nice(current) < 0))
+ set_user_nice(current, 0);
+ /* cpus_allowed? */
+ /* rt_priority? */
+ /* signals? */
+ security_task_reparent_to_init(current);
+ memcpy(current->signal->rlim, init_task.signal->rlim,
+ sizeof(current->signal->rlim));
+ atomic_inc(&(INIT_USER->__count));
+ write_unlock_irq(&tasklist_lock);
+ switch_uid(INIT_USER);
+}
+
+void __set_special_pids(pid_t session, pid_t pgrp)
+{
+ struct task_struct *curr = current;
+
+ if (curr->signal->session != session) {
+ detach_pid(curr, PIDTYPE_SID);
+ curr->signal->session = session;
+ attach_pid(curr, PIDTYPE_SID, session);
+ }
+ if (process_group(curr) != pgrp) {
+ detach_pid(curr, PIDTYPE_PGID);
+ curr->signal->pgrp = pgrp;
+ attach_pid(curr, PIDTYPE_PGID, pgrp);
+ }
+}
+
+void set_special_pids(pid_t session, pid_t pgrp)
+{
+ write_lock_irq(&tasklist_lock);
+ __set_special_pids(session, pgrp);
+ write_unlock_irq(&tasklist_lock);
+}
+
+/*
+ * Let kernel threads use this to say that they
+ * allow a certain signal (since daemonize() will
+ * have disabled all of them by default).
+ */
+int allow_signal(int sig)
+{
+ if (sig < 1 || sig > _NSIG)
+ return -EINVAL;
+
+ spin_lock_irq(¤t->sighand->siglock);
+ sigdelset(¤t->blocked, sig);
+ if (!current->mm) {
+ /* Kernel threads handle their own signals.
+ Let the signal code know it'll be handled, so
+ that they don't get converted to SIGKILL or
+ just silently dropped */
+ current->sighand->action[(sig)-1].sa.sa_handler = (void __user *)2;
+ }
+ recalc_sigpending();
+ spin_unlock_irq(¤t->sighand->siglock);
+ return 0;
+}
+
+EXPORT_SYMBOL(allow_signal);
+
+int disallow_signal(int sig)
+{
+ if (sig < 1 || sig > _NSIG)
+ return -EINVAL;
+
+ spin_lock_irq(¤t->sighand->siglock);
+ sigaddset(¤t->blocked, sig);
+ recalc_sigpending();
+ spin_unlock_irq(¤t->sighand->siglock);
+ return 0;
+}
+
+EXPORT_SYMBOL(disallow_signal);
+
+/*
+ * Put all the gunge required to become a kernel thread without
+ * attached user resources in one place where it belongs.
+ */
+
+void daemonize(const char *name, ...)
+{
+ va_list args;
+ struct fs_struct *fs;
+ sigset_t blocked;
+
+ va_start(args, name);
+ vsnprintf(current->comm, sizeof(current->comm), name, args);
+ va_end(args);
+
+ /*
+ * If we were started as result of loading a module, close all of the
+ * user space pages. We don't need them, and if we didn't close them
+ * they would be locked into memory.
+ */
+ exit_mm(current);
+
+ set_special_pids(1, 1);
+ down(&tty_sem);
+ current->signal->tty = NULL;
+ up(&tty_sem);
+
+ /* Block and flush all signals */
+ sigfillset(&blocked);
+ sigprocmask(SIG_BLOCK, &blocked, NULL);
+ flush_signals(current);
+
+ /* Become as one with the init task */
+
+ exit_fs(current); /* current->fs->count--; */
+ fs = init_task.fs;
+ current->fs = fs;
+ atomic_inc(&fs->count);
+ exit_files(current);
+ current->files = init_task.files;
+ atomic_inc(¤t->files->count);
+
+ reparent_to_init();
+}
+
+EXPORT_SYMBOL(daemonize);
+
+static inline void close_files(struct files_struct * files)
+{
+ int i, j;
+
+ j = 0;
+ for (;;) {
+ unsigned long set;
+ i = j * __NFDBITS;
+ if (i >= files->max_fdset || i >= files->max_fds)
+ break;
+ set = files->open_fds->fds_bits[j++];
+ while (set) {
+ if (set & 1) {
+ struct file * file = xchg(&files->fd[i], NULL);
+ if (file)
+ filp_close(file, files);
+ }
+ i++;
+ set >>= 1;
+ }
+ }
+}
+
+struct files_struct *get_files_struct(struct task_struct *task)
+{
+ struct files_struct *files;
+
+ task_lock(task);
+ files = task->files;
+ if (files)
+ atomic_inc(&files->count);
+ task_unlock(task);
+
+ return files;
+}
+
+void fastcall put_files_struct(struct files_struct *files)
+{
+ if (atomic_dec_and_test(&files->count)) {
+ close_files(files);
+ /*
+ * Free the fd and fdset arrays if we expanded them.
+ */
+ if (files->fd != &files->fd_array[0])
+ free_fd_array(files->fd, files->max_fds);
+ if (files->max_fdset > __FD_SETSIZE) {
+ free_fdset(files->open_fds, files->max_fdset);
+ free_fdset(files->close_on_exec, files->max_fdset);
+ }
+ kmem_cache_free(files_cachep, files);
+ }
+}
+
+EXPORT_SYMBOL(put_files_struct);
+
+static inline void __exit_files(struct task_struct *tsk)
+{
+ struct files_struct * files = tsk->files;
+
+ if (files) {
+ task_lock(tsk);
+ tsk->files = NULL;
+ task_unlock(tsk);
+ put_files_struct(files);
+ }
+}
+
+void exit_files(struct task_struct *tsk)
+{
+ __exit_files(tsk);
+}
+
+static inline 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)) {
+ dput(fs->root);
+ mntput(fs->rootmnt);
+ dput(fs->pwd);
+ mntput(fs->pwdmnt);
+ if (fs->altroot) {
+ dput(fs->altroot);
+ mntput(fs->altrootmnt);
+ }
+ kmem_cache_free(fs_cachep, fs);
+ }
+}
+
+void put_fs_struct(struct fs_struct *fs)
+{
+ __put_fs_struct(fs);
+}
+
+static inline void __exit_fs(struct task_struct *tsk)
+{
+ struct fs_struct * fs = tsk->fs;
+
+ if (fs) {
+ task_lock(tsk);
+ tsk->fs = NULL;
+ task_unlock(tsk);
+ __put_fs_struct(fs);
+ }
+}
+
+void exit_fs(struct task_struct *tsk)
+{
+ __exit_fs(tsk);
+}
+
+EXPORT_SYMBOL_GPL(exit_fs);
+
+/*
+ * Turn us into a lazy TLB process if we
+ * aren't already..
+ */
+void exit_mm(struct task_struct * tsk)
+{
+ struct mm_struct *mm = tsk->mm;
+
+ mm_release(tsk, mm);
+ if (!mm)
+ return;
+ /*
+ * Serialize with any possible pending coredump.
+ * We must hold mmap_sem around checking core_waiters
+ * and clearing tsk->mm. The core-inducing thread
+ * will increment core_waiters for each thread in the
+ * group with ->mm != NULL.
+ */
+ down_read(&mm->mmap_sem);
+ if (mm->core_waiters) {
+ up_read(&mm->mmap_sem);
+ down_write(&mm->mmap_sem);
+ if (!--mm->core_waiters)
+ complete(mm->core_startup_done);
+ up_write(&mm->mmap_sem);
+
+ wait_for_completion(&mm->core_done);
+ down_read(&mm->mmap_sem);
+ }
+ atomic_inc(&mm->mm_count);
+ if (mm != tsk->active_mm) BUG();
+ /* more a memory barrier than a real lock */
+ task_lock(tsk);
+ tsk->mm = NULL;
+ up_read(&mm->mmap_sem);
+ enter_lazy_tlb(mm, current);
+ task_unlock(tsk);
+ mmput(mm);
+}
+
+static inline void choose_new_parent(task_t *p, task_t *reaper, task_t *child_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);
+ p->real_parent = reaper;
+ if (p->parent == p->real_parent)
+ BUG();
+}
+
+static inline void reparent_thread(task_t *p, task_t *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, (void *) 0, p);
+
+ /* Move the child from its dying parent to the new one. */
+ if (unlikely(traced)) {
+ /* Preserve ptrace links if someone else is tracing this child. */
+ list_del_init(&p->ptrace_list);
+ if (p->parent != p->real_parent)
+ list_add(&p->ptrace_list, &p->real_parent->ptrace_children);
+ } else {
+ /* If this child is being traced, then we're the one tracing it
+ * anyway, so let go of it.
+ */
+ p->ptrace = 0;
+ list_del_init(&p->sibling);
+ p->parent = p->real_parent;
+ list_add_tail(&p->sibling, &p->parent->children);
+
+ /* 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 it was at a trace stop, turn it into
+ * a normal stop since it's no longer being
+ * traced.
+ */
+ ptrace_untrace(p);
+ }
+ }
+
+ /*
+ * 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)) &&
+ (p->signal->session == father->signal->session)) {
+ int pgrp = process_group(p);
+
+ if (will_become_orphaned_pgrp(pgrp, NULL) && has_stopped_jobs(pgrp)) {
+ __kill_pg_info(SIGHUP, (void *)1, pgrp);
+ __kill_pg_info(SIGCONT, (void *)1, 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")
+ */
+static inline void forget_original_parent(struct task_struct * father,
+ struct list_head *to_release)
+{
+ struct task_struct *p, *reaper = father;
+ struct list_head *_p, *_n;
+
+ do {
+ reaper = next_thread(reaper);
+ if (reaper == father) {
+ reaper = child_reaper;
+ break;
+ }
+ } while (reaper->exit_state);
+
+ /*
+ * There are only two places where our children can be:
+ *
+ * - in our child list
+ * - in our ptraced child list
+ *
+ * Search them and reparent children.
+ */
+ list_for_each_safe(_p, _n, &father->children) {
+ int ptrace;
+ p = list_entry(_p,struct task_struct,sibling);
+
+ ptrace = p->ptrace;
+
+ /* if father isn't the real parent, then ptrace must be enabled */
+ BUG_ON(father != p->real_parent && !ptrace);
+
+ if (father == p->real_parent) {
+ /* reparent with a reaper, real father it's us */
+ choose_new_parent(p, reaper, child_reaper);
+ reparent_thread(p, father, 0);
+ } else {
+ /* reparent ptraced task to its real parent */
+ __ptrace_unlink (p);
+ if (p->exit_state == EXIT_ZOMBIE && p->exit_signal != -1 &&
+ thread_group_empty(p))
+ do_notify_parent(p, p->exit_signal);
+ }
+
+ /*
+ * if the ptraced child is a zombie with exit_signal == -1
+ * we must collect it before we exit, or it will remain
+ * zombie forever since we prevented it from self-reap itself
+ * 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_for_each_safe(_p, _n, &father->ptrace_children) {
+ p = list_entry(_p,struct task_struct,ptrace_list);
+ choose_new_parent(p, reaper, child_reaper);
+ reparent_thread(p, father, 1);
+ }
+}
+
+/*
+ * Send signals to all our closest relatives so that they know
+ * to properly mourn us..
+ */
+static void exit_notify(struct task_struct *tsk)
+{
+ 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);
+
+ /*
+ * This does two things:
+ *
+ * A. Make init inherit all the child processes
+ * B. Check to see if any process groups have become orphaned
+ * 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)
+ */
+
+ INIT_LIST_HEAD(&ptrace_dead);
+ forget_original_parent(tsk, &ptrace_dead);
+ BUG_ON(!list_empty(&tsk->children));
+ BUG_ON(!list_empty(&tsk->ptrace_children));
+
+ /*
+ * Check to see if any process groups have become orphaned
+ * 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)
+ *
+ * Case i: Our father is in a different pgrp than we are
+ * 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)) &&
+ (t->signal->session == tsk->signal->session) &&
+ will_become_orphaned_pgrp(process_group(tsk), tsk) &&
+ has_stopped_jobs(process_group(tsk))) {
+ __kill_pg_info(SIGHUP, (void *)1, process_group(tsk));
+ __kill_pg_info(SIGCONT, (void *)1, process_group(tsk));
+ }
+
+ /* Let father know we died
+ *
+ * Thread signals are configurable, but you aren't going to use
+ * that to send signals to arbitary processes.
+ * That stops right now.
+ *
+ * If the parent exec id doesn't match the exec id we saved
+ * when we started then we know the parent has changed security
+ * domain.
+ *
+ * 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)
+ && !capable(CAP_KILL))
+ tsk->exit_signal = SIGCHLD;
+
+
+ /* If something other than our normal parent is ptracing us, then
+ * send it a SIGCHLD instead of honoring exit_signal. exit_signal
+ * only has special meaning to our real parent.
+ */
+ if (tsk->exit_signal != -1 && thread_group_empty(tsk)) {
+ int signal = tsk->parent == tsk->real_parent ? tsk->exit_signal : SIGCHLD;
+ do_notify_parent(tsk, signal);
+ } else if (tsk->ptrace) {
+ do_notify_parent(tsk, SIGCHLD);
+ }
+
+ state = EXIT_ZOMBIE;
+ if (tsk->exit_signal == -1 &&
+ (likely(tsk->ptrace == 0) ||
+ unlikely(tsk->parent->signal->flags & SIGNAL_GROUP_EXIT)))
+ state = EXIT_DEAD;
+ tsk->exit_state = state;
+
+ write_unlock_irq(&tasklist_lock);
+
+ list_for_each_safe(_p, _n, &ptrace_dead) {
+ list_del_init(_p);
+ t = list_entry(_p,struct task_struct,ptrace_list);
+ release_task(t);
+ }
+
+ /* If the process is dead, release it - nobody will wait for it */
+ if (state == EXIT_DEAD)
+ release_task(tsk);
+
+ /* PF_DEAD causes final put_task_struct after we schedule. */
+ preempt_disable();
+ tsk->flags |= PF_DEAD;
+}
+
+fastcall NORET_TYPE void do_exit(long code)
+{
+ struct task_struct *tsk = current;
+ int group_dead;
+
+ profile_task_exit(tsk);
+
+ if (unlikely(in_interrupt()))
+ panic("Aiee, killing interrupt handler!");
+ if (unlikely(!tsk->pid))
+ panic("Attempted to kill the idle task!");
+ if (unlikely(tsk->pid == 1))
+ panic("Attempted to kill init!");
+ if (tsk->io_context)
+ exit_io_context();
+
+ if (unlikely(current->ptrace & PT_TRACE_EXIT)) {
+ current->ptrace_message = code;
+ ptrace_notify((PTRACE_EVENT_EXIT << 8) | SIGTRAP);
+ }
+
+ 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());
+
+ acct_update_integrals(tsk);
+ update_mem_hiwater(tsk);
+ group_dead = atomic_dec_and_test(&tsk->signal->live);
+ if (group_dead) {
+ del_timer_sync(&tsk->signal->real_timer);
+ acct_process(code);
+ }
+ exit_mm(tsk);
+
+ exit_sem(tsk);
+ __exit_files(tsk);
+ __exit_fs(tsk);
+ exit_namespace(tsk);
+ exit_thread();
+ cpuset_exit(tsk);
+ exit_keys(tsk);
+
+ if (group_dead && tsk->signal->leader)
+ disassociate_ctty(1);
+
+ module_put(tsk->thread_info->exec_domain->module);
+ if (tsk->binfmt)
+ module_put(tsk->binfmt->module);
+
+ tsk->exit_code = code;
+ exit_notify(tsk);
+#ifdef CONFIG_NUMA
+ mpol_free(tsk->mempolicy);
+ tsk->mempolicy = NULL;
+#endif
+
+ BUG_ON(!(current->flags & PF_DEAD));
+ schedule();
+ BUG();
+ /* Avoid "noreturn function does return". */
+ for (;;) ;
+}
+
+NORET_TYPE void complete_and_exit(struct completion *comp, long code)
+{
+ if (comp)
+ complete(comp);
+
+ do_exit(code);
+}
+
+EXPORT_SYMBOL(complete_and_exit);
+
+asmlinkage long sys_exit(int error_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).
+ */
+NORET_TYPE void
+do_group_exit(int exit_code)
+{
+ BUG_ON(exit_code & 0x80); /* core dumps don't get here */
+
+ if (current->signal->flags & SIGNAL_GROUP_EXIT)
+ exit_code = current->signal->group_exit_code;
+ 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. */
+ exit_code = sig->group_exit_code;
+ else {
+ sig->flags = SIGNAL_GROUP_EXIT;
+ sig->group_exit_code = exit_code;
+ zap_other_threads(current);
+ }
+ spin_unlock_irq(&sighand->siglock);
+ read_unlock(&tasklist_lock);
+ }
+
+ do_exit(exit_code);
+ /* NOTREACHED */
+}
+
+/*
+ * this kills every thread in the thread group. Note that any externally
+ * wait4()-ing process will get the correct exit code - even if this
+ * thread is not the thread group leader.
+ */
+asmlinkage void sys_exit_group(int error_code)
+{
+ do_group_exit((error_code & 0xff) << 8);
+}
+
+static int eligible_child(pid_t pid, int options, task_t *p)
+{
+ if (pid > 0) {
+ if (p->pid != pid)
+ return 0;
+ } else if (!pid) {
+ if (process_group(p) != process_group(current))
+ return 0;
+ } else if (pid != -1) {
+ if (process_group(p) != -pid)
+ return 0;
+ }
+
+ /*
+ * Do not consider detached threads that are
+ * not ptraced:
+ */
+ if (p->exit_signal == -1 && !p->ptrace)
+ return 0;
+
+ /* Wait for all children (clone and not) if __WALL is set;
+ * otherwise, wait for clone children *only* if __WCLONE is
+ * set; otherwise, wait for non-clone children *only*. (Note:
+ * A "clone" child here is one that reports to its parent
+ * using a signal other than SIGCHLD.) */
+ 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 (current->tgid != p->tgid && delay_group_leader(p))
+ return 2;
+
+ if (security_task_wait(p))
+ return 0;
+
+ return 1;
+}
+
+static int wait_noreap_copyout(task_t *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);
+ if (!retval)
+ retval = put_user(0, &infop->si_errno);
+ if (!retval)
+ retval = put_user((short)why, &infop->si_code);
+ if (!retval)
+ retval = put_user(pid, &infop->si_pid);
+ if (!retval)
+ retval = put_user(uid, &infop->si_uid);
+ if (!retval)
+ retval = put_user(status, &infop->si_status);
+ if (!retval)
+ retval = pid;
+ return retval;
+}
+
+/*
+ * Handle sys_wait4 work for one task in state EXIT_ZOMBIE. We hold
+ * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
+ * 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,
+ struct siginfo __user *infop,
+ int __user *stat_addr, struct rusage __user *ru)
+{
+ unsigned long state;
+ int retval;
+ int status;
+
+ 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) {
+ why = CLD_EXITED;
+ status = exit_code >> 8;
+ } else {
+ why = (exit_code & 0x80) ? CLD_DUMPED : CLD_KILLED;
+ status = exit_code & 0x7f;
+ }
+ return wait_noreap_copyout(p, pid, uid, why,
+ status, infop, ru);
+ }
+
+ /*
+ * Try to move the task's state to DEAD
+ * only one thread is allowed to do this:
+ */
+ state = xchg(&p->exit_state, EXIT_DEAD);
+ if (state != EXIT_ZOMBIE) {
+ 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)) {
+ /*
+ * The resource counters for the group leader are in its
+ * own task_struct. Those for dead threads in the group
+ * are in its signal_struct, as are those for the child
+ * processes it has previously reaped. All these
+ * accumulate in the parent's signal_struct c* fields.
+ *
+ * We don't bother to take a lock here to protect these
+ * p->signal fields, because they are only touched by
+ * __exit_signal, which runs with tasklist_lock
+ * write-locked anyway, and so is excluded here. We do
+ * need to protect the access to p->parent->signal fields,
+ * as other threads in the parent group can be right
+ * here reaping other children at the same time.
+ */
+ spin_lock_irq(&p->parent->sighand->siglock);
+ p->parent->signal->cutime =
+ cputime_add(p->parent->signal->cutime,
+ cputime_add(p->utime,
+ cputime_add(p->signal->utime,
+ p->signal->cutime)));
+ p->parent->signal->cstime =
+ cputime_add(p->parent->signal->cstime,
+ cputime_add(p->stime,
+ cputime_add(p->signal->stime,
+ p->signal->cstime)));
+ p->parent->signal->cmin_flt +=
+ p->min_flt + p->signal->min_flt + p->signal->cmin_flt;
+ p->parent->signal->cmaj_flt +=
+ p->maj_flt + p->signal->maj_flt + p->signal->cmaj_flt;
+ p->parent->signal->cnvcsw +=
+ p->nvcsw + p->signal->nvcsw + p->signal->cnvcsw;
+ p->parent->signal->cnivcsw +=
+ p->nivcsw + p->signal->nivcsw + p->signal->cnivcsw;
+ spin_unlock_irq(&p->parent->sighand->siglock);
+ }
+
+ /*
+ * Now we are sure this task is interesting, and no other
+ * thread can reap it because we set its state to EXIT_DEAD.
+ */
+ read_unlock(&tasklist_lock);
+
+ retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
+ status = (p->signal->flags & SIGNAL_GROUP_EXIT)
+ ? p->signal->group_exit_code : p->exit_code;
+ if (!retval && stat_addr)
+ retval = put_user(status, stat_addr);
+ if (!retval && infop)
+ retval = put_user(SIGCHLD, &infop->si_signo);
+ if (!retval && infop)
+ retval = put_user(0, &infop->si_errno);
+ if (!retval && infop) {
+ int why;
+
+ if ((status & 0x7f) == 0) {
+ why = CLD_EXITED;
+ status >>= 8;
+ } else {
+ why = (status & 0x80) ? CLD_DUMPED : CLD_KILLED;
+ status &= 0x7f;
+ }
+ retval = put_user((short)why, &infop->si_code);
+ if (!retval)
+ retval = put_user(status, &infop->si_status);
+ }
+ if (!retval && infop)
+ retval = put_user(p->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) {
+ 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.
+ */
+ if (p->exit_signal != -1) {
+ do_notify_parent(p, p->exit_signal);
+ if (p->exit_signal != -1)
+ p = NULL;
+ }
+ }
+ write_unlock_irq(&tasklist_lock);
+ }
+ if (p != NULL)
+ release_task(p);
+ BUG_ON(!retval);
+ return retval;
+}
+
+/*
+ * Handle sys_wait4 work for one task in state TASK_STOPPED. We hold
+ * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
+ * 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,
+ int __user *stat_addr, struct rusage __user *ru)
+{
+ int retval, exit_code;
+
+ if (!p->exit_code)
+ return 0;
+ if (delayed_group_leader && !(p->ptrace & PT_PTRACED) &&
+ p->signal && 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.
+ */
+ return 0;
+
+ /*
+ * Now we are pretty sure this task is interesting.
+ * Make sure it doesn't get reaped out from under us while we
+ * give up the lock and then examine it below. We don't want to
+ * keep holding onto the tasklist_lock while we call getrusage and
+ * possibly take page faults for user memory.
+ */
+ get_task_struct(p);
+ 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_STOPPED))
+ goto bail_ref;
+ return wait_noreap_copyout(p, pid, uid,
+ why, (exit_code << 8) | 0x7f,
+ 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, p->parent);
+
+ write_unlock_irq(&tasklist_lock);
+
+ retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
+ if (!retval && stat_addr)
+ retval = put_user((exit_code << 8) | 0x7f, stat_addr);
+ if (!retval && infop)
+ retval = put_user(SIGCHLD, &infop->si_signo);
+ 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);
+ if (!retval && infop)
+ retval = put_user(exit_code, &infop->si_status);
+ if (!retval && infop)
+ retval = put_user(p->pid, &infop->si_pid);
+ if (!retval && infop)
+ retval = put_user(p->uid, &infop->si_uid);
+ if (!retval)
+ retval = p->pid;
+ put_task_struct(p);
+
+ BUG_ON(!retval);
+ return retval;
+}
+
+/*
+ * Handle do_wait work for one task in a live, non-stopped state.
+ * read_lock(&tasklist_lock) on entry. If we return zero, we still hold
+ * 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,
+ struct siginfo __user *infop,
+ int __user *stat_addr, struct rusage __user *ru)
+{
+ int retval;
+ pid_t pid;
+ uid_t uid;
+
+ if (unlikely(!p->signal))
+ return 0;
+
+ if (!(p->signal->flags & SIGNAL_STOP_CONTINUED))
+ return 0;
+
+ spin_lock_irq(&p->sighand->siglock);
+ /* Re-check with the lock held. */
+ if (!(p->signal->flags & SIGNAL_STOP_CONTINUED)) {
+ spin_unlock_irq(&p->sighand->siglock);
+ return 0;
+ }
+ if (!noreap)
+ p->signal->flags &= ~SIGNAL_STOP_CONTINUED;
+ spin_unlock_irq(&p->sighand->siglock);
+
+ pid = p->pid;
+ uid = p->uid;
+ get_task_struct(p);
+ read_unlock(&tasklist_lock);
+
+ if (!infop) {
+ retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
+ put_task_struct(p);
+ if (!retval && stat_addr)
+ retval = put_user(0xffff, stat_addr);
+ if (!retval)
+ retval = p->pid;
+ } else {
+ retval = wait_noreap_copyout(p, pid, uid,
+ CLD_CONTINUED, SIGCONT,
+ infop, ru);
+ BUG_ON(retval == 0);
+ }
+
+ 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)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ struct task_struct *tsk;
+ int flag, retval;
+
+ add_wait_queue(¤t->signal->wait_chldexit,&wait);
+repeat:
+ /*
+ * 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;
+ 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);
+ if (!ret)
+ continue;
+
+ switch (p->state) {
+ case TASK_TRACED:
+ if (!my_ptrace_child(p))
+ continue;
+ /*FALLTHROUGH*/
+ case TASK_STOPPED:
+ /*
+ * It's stopped now, so it might later
+ * continue, exit, or stop again.
+ */
+ flag = 1;
+ if (!(options & WUNTRACED) &&
+ !my_ptrace_child(p))
+ 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)
+ 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:
+ /*
+ * 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;
+ }
+ }
+ if (!flag) {
+ list_for_each(_p, &tsk->ptrace_children) {
+ p = list_entry(_p, struct task_struct,
+ ptrace_list);
+ if (!eligible_child(pid, options, p))
+ continue;
+ flag = 1;
+ break;
+ }
+ }
+ if (options & __WNOTHREAD)
+ break;
+ tsk = next_thread(tsk);
+ if (tsk->signal != current->signal)
+ BUG();
+ } while (tsk != current);
+
+ read_unlock(&tasklist_lock);
+ if (flag) {
+ retval = 0;
+ if (options & WNOHANG)
+ goto end;
+ retval = -ERESTARTSYS;
+ if (signal_pending(current))
+ goto end;
+ schedule();
+ goto repeat;
+ }
+ retval = -ECHILD;
+end:
+ current->state = TASK_RUNNING;
+ remove_wait_queue(¤t->signal->wait_chldexit,&wait);
+ if (infop) {
+ if (retval > 0)
+ retval = 0;
+ else {
+ /*
+ * For a WNOHANG return, clear out all the fields
+ * we would set so the user can easily tell the
+ * difference.
+ */
+ if (!retval)
+ retval = put_user(0, &infop->si_signo);
+ if (!retval)
+ retval = put_user(0, &infop->si_errno);
+ if (!retval)
+ retval = put_user(0, &infop->si_code);
+ if (!retval)
+ retval = put_user(0, &infop->si_pid);
+ if (!retval)
+ retval = put_user(0, &infop->si_uid);
+ if (!retval)
+ retval = put_user(0, &infop->si_status);
+ }
+ }
+ return retval;
+}
+
+asmlinkage long sys_waitid(int which, pid_t pid,
+ struct siginfo __user *infop, int options,
+ struct rusage __user *ru)
+{
+ long ret;
+
+ if (options & ~(WNOHANG|WNOWAIT|WEXITED|WSTOPPED|WCONTINUED))
+ return -EINVAL;
+ if (!(options & (WEXITED|WSTOPPED|WCONTINUED)))
+ return -EINVAL;
+
+ switch (which) {
+ case P_ALL:
+ pid = -1;
+ break;
+ case P_PID:
+ if (pid <= 0)
+ return -EINVAL;
+ break;
+ case P_PGID:
+ if (pid <= 0)
+ return -EINVAL;
+ pid = -pid;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = do_wait(pid, options, infop, NULL, ru);
+
+ /* avoid REGPARM breakage on x86: */
+ prevent_tail_call(ret);
+ return ret;
+}
+
+asmlinkage long sys_wait4(pid_t pid, int __user *stat_addr,
+ int options, struct rusage __user *ru)
+{
+ long ret;
+
+ if (options & ~(WNOHANG|WUNTRACED|WCONTINUED|
+ __WNOTHREAD|__WCLONE|__WALL))
+ return -EINVAL;
+ ret = do_wait(pid, options | WEXITED, NULL, stat_addr, ru);
+
+ /* avoid REGPARM breakage on x86: */
+ prevent_tail_call(ret);
+ return ret;
+}
+
+#ifdef __ARCH_WANT_SYS_WAITPID
+
+/*
+ * sys_waitpid() remains for compatibility. waitpid() should be
+ * implemented by calling sys_wait4() from libc.a.
+ */
+asmlinkage long sys_waitpid(pid_t pid, int __user *stat_addr, int options)
+{
+ return sys_wait4(pid, stat_addr, options, NULL);
+}
+
+#endif