#include <linux/completion.h>
#include <linux/personality.h>
#include <linux/tty.h>
-#include <linux/mnt_namespace.h>
#include <linux/iocontext.h>
#include <linux/key.h>
#include <linux/security.h>
#include <linux/tracehook.h>
#include <linux/fs_struct.h>
#include <linux/init_task.h>
-#include <trace/sched.h>
+#include <linux/perf_event.h>
+#include <trace/events/sched.h>
+#include <linux/hw_breakpoint.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
-#include "cred-internals.h"
-
-DEFINE_TRACE(sched_process_free);
-DEFINE_TRACE(sched_process_exit);
-DEFINE_TRACE(sched_process_wait);
static void exit_mm(struct task_struct * tsk);
-static void __unhash_process(struct task_struct *p)
+static void __unhash_process(struct task_struct *p, bool group_dead)
{
nr_threads--;
detach_pid(p, PIDTYPE_PID);
- if (thread_group_leader(p)) {
+ if (group_dead) {
detach_pid(p, PIDTYPE_PGID);
detach_pid(p, PIDTYPE_SID);
list_del_rcu(&p->tasks);
+ list_del_init(&p->sibling);
__get_cpu_var(process_counts)--;
}
list_del_rcu(&p->thread_group);
- list_del_init(&p->sibling);
}
/*
static void __exit_signal(struct task_struct *tsk)
{
struct signal_struct *sig = tsk->signal;
+ bool group_dead = thread_group_leader(tsk);
struct sighand_struct *sighand;
+ struct tty_struct *uninitialized_var(tty);
- BUG_ON(!sig);
- BUG_ON(!atomic_read(&sig->count));
-
- sighand = rcu_dereference(tsk->sighand);
+ sighand = rcu_dereference_check(tsk->sighand,
+ rcu_read_lock_held() ||
+ lockdep_tasklist_lock_is_held());
spin_lock(&sighand->siglock);
posix_cpu_timers_exit(tsk);
- if (atomic_dec_and_test(&sig->count))
+ if (group_dead) {
posix_cpu_timers_exit_group(tsk);
- else {
+ tty = sig->tty;
+ sig->tty = NULL;
+ } 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)
+ if (sig->notify_count > 0 && !--sig->notify_count)
wake_up_process(sig->group_exit_task);
if (tsk == sig->curr_target)
* 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, task_utime(tsk));
- sig->stime = cputime_add(sig->stime, task_stime(tsk));
- sig->gtime = cputime_add(sig->gtime, task_gtime(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->oublock += task_io_get_oublock(tsk);
task_io_accounting_add(&sig->ioac, &tsk->ioac);
sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
- sig = NULL; /* Marker for below. */
}
- __unhash_process(tsk);
+ sig->nr_threads--;
+ __unhash_process(tsk, group_dead);
/*
* Do this under ->siglock, we can race with another thread
* doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals.
*/
flush_sigqueue(&tsk->pending);
-
- tsk->signal = NULL;
tsk->sighand = NULL;
spin_unlock(&sighand->siglock);
__cleanup_sighand(sighand);
clear_tsk_thread_flag(tsk,TIF_SIGPENDING);
- if (sig) {
+ if (group_dead) {
flush_sigqueue(&sig->shared_pending);
- taskstats_tgid_free(sig);
- /*
- * Make sure ->signal can't go away under rq->lock,
- * see account_group_exec_runtime().
- */
- task_rq_unlock_wait(tsk);
- __cleanup_signal(sig);
+ tty_kref_put(tty);
}
}
{
struct task_struct *tsk = container_of(rhp, struct task_struct, rcu);
-#ifdef CONFIG_PERF_COUNTERS
- WARN_ON_ONCE(!list_empty(&tsk->perf_counter_ctx.counter_list));
+#ifdef CONFIG_PERF_EVENTS
+ WARN_ON_ONCE(tsk->perf_event_ctxp);
#endif
trace_sched_process_free(tsk);
put_task_struct(tsk);
repeat:
tracehook_prepare_release_task(p);
/* don't need to get the RCU readlock here - the process is dead and
- * can't be modifying its own credentials */
+ * can't be modifying its own credentials. But shut RCU-lockdep up */
+ rcu_read_lock();
atomic_dec(&__task_cred(p)->user->processes);
+ rcu_read_unlock();
proc_flush_task(p);
- /*
- * Flush inherited counters to the parent - before the parent
- * gets woken up by child-exit notifications.
- */
- perf_counter_exit_task(p);
-
write_lock_irq(&tasklist_lock);
tracehook_finish_release_task(p);
__exit_signal(p);
}
/*
- * Let kernel threads use this to say that they
- * allow a certain signal (since daemonize() will
- * have disabled all of them by default).
+ * Let kernel threads use this to say that they allow a certain signal.
+ * Must not be used if kthread was cloned with CLONE_SIGHAND.
*/
int allow_signal(int sig)
{
return -EINVAL;
spin_lock_irq(¤t->sighand->siglock);
+ /* This is only needed for daemonize()'ed kthreads */
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;
- }
+ /*
+ * 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;
/*
* It is safe to dereference the fd table without RCU or
* ->file_lock because this is the last reference to the
- * files structure.
+ * files structure. But use RCU to shut RCU-lockdep up.
*/
+ rcu_read_lock();
fdt = files_fdtable(files);
+ rcu_read_unlock();
for (;;) {
unsigned long set;
i = j * __NFDBITS;
* at the end of the RCU grace period. Otherwise,
* you can free files immediately.
*/
+ rcu_read_lock();
fdt = files_fdtable(files);
if (fdt != &files->fdtab)
kmem_cache_free(files_cachep, files);
free_fdtable(fdt);
+ rcu_read_unlock();
}
}
/*
* Search in the siblings
*/
- list_for_each_entry(c, &p->parent->children, sibling) {
+ list_for_each_entry(c, &p->real_parent->children, sibling) {
if (c->mm == mm)
goto assign_new_owner;
}
/*
* Any that need to be release_task'd are put on the @dead list.
*/
-static void reparent_thread(struct task_struct *father, struct task_struct *p,
+static void reparent_leader(struct task_struct *father, struct task_struct *p,
struct list_head *dead)
{
- if (p->pdeath_signal)
- group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p);
-
list_move_tail(&p->sibling, &p->real_parent->children);
if (task_detached(p))
p->exit_signal = SIGCHLD;
/* If it has exited notify the new parent about this child's death. */
- if (!p->ptrace &&
+ if (!task_ptrace(p) &&
p->exit_state == EXIT_ZOMBIE && thread_group_empty(p)) {
do_notify_parent(p, p->exit_signal);
if (task_detached(p)) {
reaper = find_new_reaper(father);
list_for_each_entry_safe(p, n, &father->children, sibling) {
- p->real_parent = reaper;
- if (p->parent == father) {
- BUG_ON(p->ptrace);
- p->parent = p->real_parent;
- }
- reparent_thread(father, p, &dead_children);
+ struct task_struct *t = p;
+ do {
+ t->real_parent = reaper;
+ if (t->parent == father) {
+ BUG_ON(task_ptrace(t));
+ t->parent = t->real_parent;
+ }
+ if (t->pdeath_signal)
+ group_send_sig_info(t->pdeath_signal,
+ SEND_SIG_NOINFO, t);
+ } while_each_thread(p, t);
+ reparent_leader(father, p, &dead_children);
}
write_unlock_irq(&tasklist_lock);
tsk->exit_state = signal == DEATH_REAP ? EXIT_DEAD : EXIT_ZOMBIE;
- /* mt-exec, de_thread() is waiting for us */
- if (thread_group_leader(tsk) &&
- tsk->signal->group_exit_task &&
- tsk->signal->notify_count < 0)
+ /* mt-exec, de_thread() is waiting for group leader */
+ if (unlikely(tsk->signal->notify_count < 0))
wake_up_process(tsk->signal->group_exit_task);
-
write_unlock_irq(&tasklist_lock);
tracehook_report_death(tsk, signal, cookie, group_dead);
tracehook_report_exit(&code);
+ validate_creds_for_do_exit(tsk);
+
/*
* We're taking recursive faults here in do_exit. Safest is to just
* leave this task alone and wait for reboot.
* an exiting task cleaning up the robust pi futexes.
*/
smp_mb();
- spin_unlock_wait(&tsk->pi_lock);
+ raw_spin_unlock_wait(&tsk->pi_lock);
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
preempt_count());
acct_update_integrals(tsk);
-
+ /* sync mm's RSS info before statistics gathering */
+ if (tsk->mm)
+ sync_mm_rss(tsk, tsk->mm);
group_dead = atomic_dec_and_test(&tsk->signal->live);
if (group_dead) {
hrtimer_cancel(&tsk->signal->real_timer);
exit_itimers(tsk->signal);
+ if (tsk->mm)
+ setmax_mm_hiwater_rss(&tsk->signal->maxrss, tsk->mm);
}
acct_collect(code, group_dead);
if (group_dead)
exit_thread();
cgroup_exit(tsk, 1);
- if (group_dead && tsk->signal->leader)
+ if (group_dead)
disassociate_ctty(1);
module_put(task_thread_info(tsk)->exec_domain->module);
- if (tsk->binfmt)
- module_put(tsk->binfmt->module);
proc_exit_connector(tsk);
+
+ /*
+ * FIXME: do that only when needed, using sched_exit tracepoint
+ */
+ flush_ptrace_hw_breakpoint(tsk);
+ /*
+ * Flush inherited counters to the parent - before the parent
+ * gets woken up by child-exit notifications.
+ */
+ perf_event_exit_task(tsk);
+
exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA
+ task_lock(tsk);
mpol_put(tsk->mempolicy);
tsk->mempolicy = NULL;
+ task_unlock(tsk);
#endif
#ifdef CONFIG_FUTEX
- if (unlikely(!list_empty(&tsk->pi_state_list)))
- exit_pi_state_list(tsk);
if (unlikely(current->pi_state_cache))
kfree(current->pi_state_cache);
#endif
tsk->flags |= PF_EXITPIDONE;
if (tsk->io_context)
- exit_io_context();
+ exit_io_context(tsk);
if (tsk->splice_pipe)
__free_pipe_info(tsk->splice_pipe);
+ validate_creds_for_do_exit(tsk);
+
preempt_disable();
+ exit_rcu();
/* causes final put_task_struct in finish_task_switch(). */
tsk->state = TASK_DEAD;
schedule();
return 0;
}
-static struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
+struct wait_opts {
+ enum pid_type wo_type;
+ int wo_flags;
+ struct pid *wo_pid;
+
+ struct siginfo __user *wo_info;
+ int __user *wo_stat;
+ struct rusage __user *wo_rusage;
+
+ wait_queue_t child_wait;
+ int notask_error;
+};
+
+static inline
+struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
{
- struct pid *pid = NULL;
- if (type == PIDTYPE_PID)
- pid = task->pids[type].pid;
- else if (type < PIDTYPE_MAX)
- pid = task->group_leader->pids[type].pid;
- return pid;
+ if (type != PIDTYPE_PID)
+ task = task->group_leader;
+ return task->pids[type].pid;
}
-static int eligible_child(enum pid_type type, struct pid *pid, int options,
- struct task_struct *p)
+static int eligible_pid(struct wait_opts *wo, struct task_struct *p)
{
- int err;
-
- if (type < PIDTYPE_MAX) {
- if (task_pid_type(p, type) != pid)
- return 0;
- }
+ return wo->wo_type == PIDTYPE_MAX ||
+ task_pid_type(p, wo->wo_type) == wo->wo_pid;
+}
+static int eligible_child(struct wait_opts *wo, struct task_struct *p)
+{
+ if (!eligible_pid(wo, p))
+ 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))
+ if (((p->exit_signal != SIGCHLD) ^ !!(wo->wo_flags & __WCLONE))
+ && !(wo->wo_flags & __WALL))
return 0;
- err = security_task_wait(p);
- if (err)
- return err;
-
return 1;
}
-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)
+static int wait_noreap_copyout(struct wait_opts *wo, struct task_struct *p,
+ pid_t pid, uid_t uid, int why, int status)
{
- int retval = rusagep ? getrusage(p, RUSAGE_BOTH, rusagep) : 0;
+ struct siginfo __user *infop;
+ int retval = wo->wo_rusage
+ ? getrusage(p, RUSAGE_BOTH, wo->wo_rusage) : 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);
+ infop = wo->wo_info;
+ if (infop) {
+ 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;
* 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(struct task_struct *p, int options,
- struct siginfo __user *infop,
- int __user *stat_addr, struct rusage __user *ru)
+static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
{
unsigned long state;
int retval, status, traced;
pid_t pid = task_pid_vnr(p);
uid_t uid = __task_cred(p)->uid;
+ struct siginfo __user *infop;
- if (!likely(options & WEXITED))
+ if (!likely(wo->wo_flags & WEXITED))
return 0;
- if (unlikely(options & WNOWAIT)) {
+ if (unlikely(wo->wo_flags & WNOWAIT)) {
int exit_code = p->exit_code;
- int why, status;
+ int why;
get_task_struct(p);
read_unlock(&tasklist_lock);
why = (exit_code & 0x80) ? CLD_DUMPED : CLD_KILLED;
status = exit_code & 0x7f;
}
- return wait_noreap_copyout(p, pid, uid, why,
- status, infop, ru);
+ return wait_noreap_copyout(wo, p, pid, uid, why, status);
}
/*
}
traced = ptrace_reparented(p);
-
- if (likely(!traced)) {
+ /*
+ * It can be ptraced but not reparented, check
+ * !task_detached() to filter out sub-threads.
+ */
+ if (likely(!traced) && likely(!task_detached(p))) {
struct signal_struct *psig;
struct signal_struct *sig;
- struct task_cputime cputime;
+ unsigned long maxrss;
+ cputime_t tgutime, tgstime;
/*
* The resource counters for the group leader are in its
* 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,
+ * need to protect the access to parent->signal fields,
* as other threads in the parent group can be right
* here reaping other children at the same time.
*
- * We use thread_group_cputime() to get times for the thread
+ * We use thread_group_times() to get times for the thread
* group, which consolidates times for all threads in the
* group including the group leader.
*/
- thread_group_cputime(p, &cputime);
- spin_lock_irq(&p->parent->sighand->siglock);
- psig = p->parent->signal;
+ thread_group_times(p, &tgutime, &tgstime);
+ spin_lock_irq(&p->real_parent->sighand->siglock);
+ psig = p->real_parent->signal;
sig = p->signal;
psig->cutime =
cputime_add(psig->cutime,
- cputime_add(cputime.utime,
+ cputime_add(tgutime,
sig->cutime));
psig->cstime =
cputime_add(psig->cstime,
- cputime_add(cputime.stime,
+ cputime_add(tgstime,
sig->cstime));
psig->cgtime =
cputime_add(psig->cgtime,
psig->coublock +=
task_io_get_oublock(p) +
sig->oublock + sig->coublock;
+ maxrss = max(sig->maxrss, sig->cmaxrss);
+ if (psig->cmaxrss < maxrss)
+ psig->cmaxrss = maxrss;
task_io_accounting_add(&psig->ioac, &p->ioac);
task_io_accounting_add(&psig->ioac, &sig->ioac);
- spin_unlock_irq(&p->parent->sighand->siglock);
+ spin_unlock_irq(&p->real_parent->sighand->siglock);
}
/*
*/
read_unlock(&tasklist_lock);
- /*
- * Flush inherited counters to the parent - before the parent
- * gets woken up by child-exit notifications.
- */
- perf_counter_exit_task(p);
-
- retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
+ retval = wo->wo_rusage
+ ? getrusage(p, RUSAGE_BOTH, wo->wo_rusage) : 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 && wo->wo_stat)
+ retval = put_user(status, wo->wo_stat);
+
+ infop = wo->wo_info;
if (!retval && infop)
retval = put_user(SIGCHLD, &infop->si_signo);
if (!retval && infop)
* 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(int ptrace, struct task_struct *p,
- int options, struct siginfo __user *infop,
- int __user *stat_addr, struct rusage __user *ru)
+static int wait_task_stopped(struct wait_opts *wo,
+ int ptrace, struct task_struct *p)
{
+ struct siginfo __user *infop;
int retval, exit_code, *p_code, why;
uid_t uid = 0; /* unneeded, required by compiler */
pid_t pid;
- if (!(options & WUNTRACED))
+ /*
+ * Traditionally we see ptrace'd stopped tasks regardless of options.
+ */
+ if (!ptrace && !(wo->wo_flags & WUNTRACED))
return 0;
exit_code = 0;
if (!exit_code)
goto unlock_sig;
- if (!unlikely(options & WNOWAIT))
+ if (!unlikely(wo->wo_flags & WNOWAIT))
*p_code = 0;
/* don't need the RCU readlock here as we're holding a spinlock */
why = ptrace ? CLD_TRAPPED : CLD_STOPPED;
read_unlock(&tasklist_lock);
- if (unlikely(options & WNOWAIT))
- return wait_noreap_copyout(p, pid, uid,
- why, exit_code,
- infop, ru);
+ if (unlikely(wo->wo_flags & WNOWAIT))
+ return wait_noreap_copyout(wo, p, pid, uid, why, exit_code);
- retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
- if (!retval && stat_addr)
- retval = put_user((exit_code << 8) | 0x7f, stat_addr);
+ retval = wo->wo_rusage
+ ? getrusage(p, RUSAGE_BOTH, wo->wo_rusage) : 0;
+ if (!retval && wo->wo_stat)
+ retval = put_user((exit_code << 8) | 0x7f, wo->wo_stat);
+
+ infop = wo->wo_info;
if (!retval && infop)
retval = put_user(SIGCHLD, &infop->si_signo);
if (!retval && infop)
* 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(struct task_struct *p, int options,
- struct siginfo __user *infop,
- int __user *stat_addr, struct rusage __user *ru)
+static int wait_task_continued(struct wait_opts *wo, struct task_struct *p)
{
int retval;
pid_t pid;
uid_t uid;
- if (!unlikely(options & WCONTINUED))
+ if (!unlikely(wo->wo_flags & WCONTINUED))
return 0;
if (!(p->signal->flags & SIGNAL_STOP_CONTINUED))
spin_unlock_irq(&p->sighand->siglock);
return 0;
}
- if (!unlikely(options & WNOWAIT))
+ if (!unlikely(wo->wo_flags & WNOWAIT))
p->signal->flags &= ~SIGNAL_STOP_CONTINUED;
uid = __task_cred(p)->uid;
spin_unlock_irq(&p->sighand->siglock);
get_task_struct(p);
read_unlock(&tasklist_lock);
- if (!infop) {
- retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0;
+ if (!wo->wo_info) {
+ retval = wo->wo_rusage
+ ? getrusage(p, RUSAGE_BOTH, wo->wo_rusage) : 0;
put_task_struct(p);
- if (!retval && stat_addr)
- retval = put_user(0xffff, stat_addr);
+ if (!retval && wo->wo_stat)
+ retval = put_user(0xffff, wo->wo_stat);
if (!retval)
retval = pid;
} else {
- retval = wait_noreap_copyout(p, pid, uid,
- CLD_CONTINUED, SIGCONT,
- infop, ru);
+ retval = wait_noreap_copyout(wo, p, pid, uid,
+ CLD_CONTINUED, SIGCONT);
BUG_ON(retval == 0);
}
/*
* Consider @p for a wait by @parent.
*
- * -ECHILD should be in *@notask_error before the first call.
+ * -ECHILD should be in ->notask_error before the first call.
* Returns nonzero for a final return, when we have unlocked tasklist_lock.
* Returns zero if the search for a child should continue;
- * then *@notask_error is 0 if @p is an eligible child,
+ * then ->notask_error is 0 if @p is an eligible child,
* or another error from security_task_wait(), or still -ECHILD.
*/
-static int wait_consider_task(struct task_struct *parent, int ptrace,
- struct task_struct *p, int *notask_error,
- enum pid_type type, struct pid *pid, int options,
- struct siginfo __user *infop,
- int __user *stat_addr, struct rusage __user *ru)
+static int wait_consider_task(struct wait_opts *wo, int ptrace,
+ struct task_struct *p)
{
- int ret = eligible_child(type, pid, options, p);
+ int ret = eligible_child(wo, p);
if (!ret)
return ret;
+ ret = security_task_wait(p);
if (unlikely(ret < 0)) {
/*
* If we have not yet seen any eligible child,
* to look for security policy problems, rather
* than for mysterious wait bugs.
*/
- if (*notask_error)
- *notask_error = ret;
+ if (wo->notask_error)
+ wo->notask_error = ret;
+ return 0;
}
- if (likely(!ptrace) && unlikely(p->ptrace)) {
+ if (likely(!ptrace) && unlikely(task_ptrace(p))) {
/*
* This child is hidden by ptrace.
* We aren't allowed to see it now, but eventually we will.
*/
- *notask_error = 0;
+ wo->notask_error = 0;
return 0;
}
* We don't reap group leaders with subthreads.
*/
if (p->exit_state == EXIT_ZOMBIE && !delay_group_leader(p))
- return wait_task_zombie(p, options, infop, stat_addr, ru);
+ return wait_task_zombie(wo, p);
/*
* It's stopped or running now, so it might
* later continue, exit, or stop again.
*/
- *notask_error = 0;
+ wo->notask_error = 0;
if (task_stopped_code(p, ptrace))
- return wait_task_stopped(ptrace, p, options,
- infop, stat_addr, ru);
+ return wait_task_stopped(wo, ptrace, p);
- return wait_task_continued(p, options, infop, stat_addr, ru);
+ return wait_task_continued(wo, p);
}
/*
* Do the work of do_wait() for one thread in the group, @tsk.
*
- * -ECHILD should be in *@notask_error before the first call.
+ * -ECHILD should be in ->notask_error before the first call.
* Returns nonzero for a final return, when we have unlocked tasklist_lock.
* Returns zero if the search for a child should continue; then
- * *@notask_error is 0 if there were any eligible children,
+ * ->notask_error is 0 if there were any eligible children,
* or another error from security_task_wait(), or still -ECHILD.
*/
-static int do_wait_thread(struct task_struct *tsk, int *notask_error,
- enum pid_type type, struct pid *pid, int options,
- struct siginfo __user *infop, int __user *stat_addr,
- struct rusage __user *ru)
+static int do_wait_thread(struct wait_opts *wo, struct task_struct *tsk)
{
struct task_struct *p;
list_for_each_entry(p, &tsk->children, sibling) {
- /*
- * Do not consider detached threads.
- */
- if (!task_detached(p)) {
- int ret = wait_consider_task(tsk, 0, p, notask_error,
- type, pid, options,
- infop, stat_addr, ru);
- if (ret)
- return ret;
- }
+ int ret = wait_consider_task(wo, 0, p);
+ if (ret)
+ return ret;
}
return 0;
}
-static int ptrace_do_wait(struct task_struct *tsk, int *notask_error,
- enum pid_type type, struct pid *pid, int options,
- struct siginfo __user *infop, int __user *stat_addr,
- struct rusage __user *ru)
+static int ptrace_do_wait(struct wait_opts *wo, struct task_struct *tsk)
{
struct task_struct *p;
- /*
- * Traditionally we see ptrace'd stopped tasks regardless of options.
- */
- options |= WUNTRACED;
-
list_for_each_entry(p, &tsk->ptraced, ptrace_entry) {
- int ret = wait_consider_task(tsk, 1, p, notask_error,
- type, pid, options,
- infop, stat_addr, ru);
+ int ret = wait_consider_task(wo, 1, p);
if (ret)
return ret;
}
return 0;
}
-static long do_wait(enum pid_type type, struct pid *pid, int options,
- struct siginfo __user *infop, int __user *stat_addr,
- struct rusage __user *ru)
+static int child_wait_callback(wait_queue_t *wait, unsigned mode,
+ int sync, void *key)
+{
+ struct wait_opts *wo = container_of(wait, struct wait_opts,
+ child_wait);
+ struct task_struct *p = key;
+
+ if (!eligible_pid(wo, p))
+ return 0;
+
+ if ((wo->wo_flags & __WNOTHREAD) && wait->private != p->parent)
+ return 0;
+
+ return default_wake_function(wait, mode, sync, key);
+}
+
+void __wake_up_parent(struct task_struct *p, struct task_struct *parent)
+{
+ __wake_up_sync_key(&parent->signal->wait_chldexit,
+ TASK_INTERRUPTIBLE, 1, p);
+}
+
+static long do_wait(struct wait_opts *wo)
{
- DECLARE_WAITQUEUE(wait, current);
struct task_struct *tsk;
int retval;
- trace_sched_process_wait(pid);
+ trace_sched_process_wait(wo->wo_pid);
- add_wait_queue(¤t->signal->wait_chldexit,&wait);
+ init_waitqueue_func_entry(&wo->child_wait, child_wait_callback);
+ wo->child_wait.private = current;
+ add_wait_queue(¤t->signal->wait_chldexit, &wo->child_wait);
repeat:
/*
* If there is nothing that can match our critiera just get out.
- * We will clear @retval to zero if we see any child that might later
- * match our criteria, even if we are not able to reap it yet.
+ * We will clear ->notask_error to zero if we see any child that
+ * might later match our criteria, even if we are not able to reap
+ * it yet.
*/
- retval = -ECHILD;
- if ((type < PIDTYPE_MAX) && (!pid || hlist_empty(&pid->tasks[type])))
- goto end;
+ wo->notask_error = -ECHILD;
+ if ((wo->wo_type < PIDTYPE_MAX) &&
+ (!wo->wo_pid || hlist_empty(&wo->wo_pid->tasks[wo->wo_type])))
+ goto notask;
- current->state = TASK_INTERRUPTIBLE;
+ set_current_state(TASK_INTERRUPTIBLE);
read_lock(&tasklist_lock);
tsk = current;
do {
- int tsk_result = do_wait_thread(tsk, &retval,
- type, pid, options,
- infop, stat_addr, ru);
- if (!tsk_result)
- tsk_result = ptrace_do_wait(tsk, &retval,
- type, pid, options,
- infop, stat_addr, ru);
- if (tsk_result) {
- /*
- * tasklist_lock is unlocked and we have a final result.
- */
- retval = tsk_result;
+ retval = do_wait_thread(wo, tsk);
+ if (retval)
+ goto end;
+
+ retval = ptrace_do_wait(wo, tsk);
+ if (retval)
goto end;
- }
- if (options & __WNOTHREAD)
+ if (wo->wo_flags & __WNOTHREAD)
break;
- tsk = next_thread(tsk);
- BUG_ON(tsk->signal != current->signal);
- } while (tsk != current);
+ } while_each_thread(current, tsk);
read_unlock(&tasklist_lock);
- if (!retval && !(options & WNOHANG)) {
+notask:
+ retval = wo->notask_error;
+ if (!retval && !(wo->wo_flags & WNOHANG)) {
retval = -ERESTARTSYS;
if (!signal_pending(current)) {
schedule();
goto repeat;
}
}
-
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);
- }
- }
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(¤t->signal->wait_chldexit, &wo->child_wait);
return retval;
}
SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
infop, int, options, struct rusage __user *, ru)
{
+ struct wait_opts wo;
struct pid *pid = NULL;
enum pid_type type;
long ret;
if (type < PIDTYPE_MAX)
pid = find_get_pid(upid);
- ret = do_wait(type, pid, options, infop, NULL, ru);
+
+ wo.wo_type = type;
+ wo.wo_pid = pid;
+ wo.wo_flags = options;
+ wo.wo_info = infop;
+ wo.wo_stat = NULL;
+ wo.wo_rusage = ru;
+ ret = do_wait(&wo);
+
+ if (ret > 0) {
+ ret = 0;
+ } else if (infop) {
+ /*
+ * For a WNOHANG return, clear out all the fields
+ * we would set so the user can easily tell the
+ * difference.
+ */
+ if (!ret)
+ ret = put_user(0, &infop->si_signo);
+ if (!ret)
+ ret = put_user(0, &infop->si_errno);
+ if (!ret)
+ ret = put_user(0, &infop->si_code);
+ if (!ret)
+ ret = put_user(0, &infop->si_pid);
+ if (!ret)
+ ret = put_user(0, &infop->si_uid);
+ if (!ret)
+ ret = put_user(0, &infop->si_status);
+ }
+
put_pid(pid);
/* avoid REGPARM breakage on x86: */
SYSCALL_DEFINE4(wait4, pid_t, upid, int __user *, stat_addr,
int, options, struct rusage __user *, ru)
{
+ struct wait_opts wo;
struct pid *pid = NULL;
enum pid_type type;
long ret;
pid = find_get_pid(upid);
}
- ret = do_wait(type, pid, options | WEXITED, NULL, stat_addr, ru);
+ wo.wo_type = type;
+ wo.wo_pid = pid;
+ wo.wo_flags = options | WEXITED;
+ wo.wo_info = NULL;
+ wo.wo_stat = stat_addr;
+ wo.wo_rusage = ru;
+ ret = do_wait(&wo);
put_pid(pid);
/* avoid REGPARM breakage on x86: */
Code Review / linux-2.6.git / blobdiff