recalc_sigpending_tsk fixes

[sfrench/cifs-2.6.git] / kernel / exit.c

diff --git a/kernel/exit.c b/kernel/exit.c
index b55ed4cc91044803a45b74d568d83f9727575b8b..5b888c24e43e0ce650e554c5cec34a99f699c1fd 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -7,7 +7,6 @@
 #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>
@@ -25,8 +24,10 @@
 #include <linux/pid_namespace.h>
 #include <linux/ptrace.h>
 #include <linux/profile.h>
+#include <linux/signalfd.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>
@@ -42,6 +43,7 @@
 #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>
@@ -82,6 +84,14 @@ static void __exit_signal(struct task_struct *tsk)
        sighand = rcu_dereference(tsk->sighand);
        spin_lock(&sighand->siglock);
 
+       /*
+        * Notify that this sighand has been detached. This must
+        * be called with the tsk->sighand lock held. Also, this
+        * access tsk->sighand internally, so it must be called
+        * before tsk->sighand is reset.
+        */
+       signalfd_detach_locked(tsk);
+
        posix_cpu_timers_exit(tsk);
        if (atomic_dec_and_test(&sig->count))
                posix_cpu_timers_exit_group(tsk);
@@ -113,6 +123,8 @@ static void __exit_signal(struct task_struct *tsk)
                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 = NULL; /* Marker for below. */
        }
 
@@ -255,26 +267,25 @@ static int has_stopped_jobs(struct pid *pgrp)
 }
 
 /**
- * reparent_to_init - Reparent the calling kernel thread to the init task of the pid space that the thread belongs to.
+ * 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);
-       current->real_parent = child_reaper(current);
+       current->real_parent = current->parent = kthreadd_task;
        add_parent(current);
 
        /* Set the exit signal to SIGCHLD so we signal init on exit */
@@ -300,12 +311,12 @@ void __set_special_pids(pid_t session, pid_t pgrp)
        if (process_session(curr) != session) {
                detach_pid(curr, PIDTYPE_SID);
                set_signal_session(curr->signal, session);
-               attach_pid(curr, PIDTYPE_SID, session);
+               attach_pid(curr, PIDTYPE_SID, find_pid(session));
        }
        if (process_group(curr) != pgrp) {
                detach_pid(curr, PIDTYPE_PGID);
                curr->signal->pgrp = pgrp;
-               attach_pid(curr, PIDTYPE_PGID, pgrp);
+               attach_pid(curr, PIDTYPE_PGID, find_pid(pgrp));
        }
 }
 
@@ -348,7 +359,7 @@ int disallow_signal(int sig)
                return -EINVAL;
 
        spin_lock_irq(&current->sighand->siglock);
-       sigaddset(&current->blocked, sig);
+       current->sighand->action[(sig)-1].sa.sa_handler = SIG_IGN;
        recalc_sigpending();
        spin_unlock_irq(&current->sighand->siglock);
        return 0;
@@ -401,7 +412,7 @@ void daemonize(const char *name, ...)
        current->files = init_task.files;
        atomic_inc(&current->files->count);
 
-       reparent_to_init();
+       reparent_to_kthreadd();
 }
 
 EXPORT_SYMBOL(daemonize);
@@ -751,11 +762,8 @@ static void exit_notify(struct task_struct *tsk)
                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);
-                       }
+                       if (!signal_pending(t) && !(t->flags & PF_EXITING))
+                               recalc_sigpending_and_wake(t);
                spin_unlock_irq(&tsk->sighand->siglock);
                read_unlock(&tasklist_lock);
        }
@@ -1033,6 +1041,8 @@ asmlinkage void sys_exit_group(int error_code)
 
 static int eligible_child(pid_t pid, int options, struct task_struct *p)
 {
+       int err;
+
        if (pid > 0) {
                if (p->pid != pid)
                        return 0;
@@ -1066,8 +1076,9 @@ static int eligible_child(pid_t pid, int options, struct task_struct *p)
        if (delay_group_leader(p))
                return 2;
 
-       if (security_task_wait(p))
-               return 0;
+       err = security_task_wait(p);
+       if (err)
+               return err;
 
        return 1;
 }
@@ -1191,6 +1202,12 @@ static int wait_task_zombie(struct task_struct *p, int noreap,
                        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);
        }
 
@@ -1449,6 +1466,7 @@ static long do_wait(pid_t pid, int options, struct siginfo __user *infop,
        DECLARE_WAITQUEUE(wait, current);
        struct task_struct *tsk;
        int flag, retval;
+       int allowed, denied;
 
        add_wait_queue(&current->signal->wait_chldexit,&wait);
 repeat:
@@ -1457,6 +1475,7 @@ repeat:
         * match our criteria, even if we are not able to reap it yet.
         */
        flag = 0;
+       allowed = denied = 0;
        current->state = TASK_INTERRUPTIBLE;
        read_lock(&tasklist_lock);
        tsk = current;
@@ -1472,6 +1491,12 @@ repeat:
                        if (!ret)
                                continue;
 
+                       if (unlikely(ret < 0)) {
+                               denied = ret;
+                               continue;
+                       }
+                       allowed = 1;
+
                        switch (p->state) {
                        case TASK_TRACED:
                                /*
@@ -1570,6 +1595,8 @@ check_continued:
                goto repeat;
        }
        retval = -ECHILD;
+       if (unlikely(denied) && !allowed)
+               retval = denied;
 end:
        current->state = TASK_RUNNING;
        remove_wait_queue(&current->signal->wait_chldexit,&wait);