1 files changed, 39 insertions, 48 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index ae2b92be5fae..167e1e3ad7c6 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -40,19 +40,24 @@
 #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 <linux/blkdev.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/tracehook.h>
+#include <linux/init_task.h>
 #include <trace/sched.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);
 
@@ -113,6 +118,8 @@ static void __exit_signal(struct task_struct *tsk)
                  * 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->min_flt += tsk->min_flt;
                 sig->maj_flt += tsk->maj_flt;
@@ -121,6 +128,7 @@ static void __exit_signal(struct task_struct *tsk)
                 sig->inblock += task_io_get_inblock(tsk);
                 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. */
         }
 
@@ -165,7 +173,10 @@ void release_task(struct task_struct * p)
         int zap_leader;
 repeat:
         tracehook_prepare_release_task(p);
-        atomic_dec(&p->user->processes);
+        /* don't need to get the RCU readlock here - the process is dead and
+         * can't be modifying its own credentials */
+        atomic_dec(&__task_cred(p)->user->processes);
+
         proc_flush_task(p);
         write_lock_irq(&tasklist_lock);
         tracehook_finish_release_task(p);
@@ -340,12 +351,12 @@ static void reparent_to_kthreadd(void)
         /* 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));
+
+        atomic_inc(&init_cred.usage);
+        commit_creds(&init_cred);
         write_unlock_irq(&tasklist_lock);
-        switch_uid(INIT_USER);
 }
 
 void __set_special_pids(struct pid *pid)
@@ -634,35 +645,31 @@ retry:
         /*
          * We found no owner yet mm_users > 1: this implies that we are
          * most likely racing with swapoff (try_to_unuse()) or /proc or
-         * ptrace or page migration (get_task_mm()).  Mark owner as NULL,
-         * so that subsystems can understand the callback and take action.
+         * ptrace or page migration (get_task_mm()).  Mark owner as NULL.
          */
-        down_write(&mm->mmap_sem);
-        cgroup_mm_owner_callbacks(mm->owner, NULL);
         mm->owner = NULL;
-        up_write(&mm->mmap_sem);
         return;
 
 assign_new_owner:
         BUG_ON(c == p);
         get_task_struct(c);
-        read_unlock(&tasklist_lock);
-        down_write(&mm->mmap_sem);
         /*
          * The task_lock protects c->mm from changing.
          * We always want mm->owner->mm == mm
          */
         task_lock(c);
+        /*
+         * Delay read_unlock() till we have the task_lock()
+         * to ensure that c does not slip away underneath us
+         */
+        read_unlock(&tasklist_lock);
         if (c->mm != mm) {
                 task_unlock(c);
-                up_write(&mm->mmap_sem);
                 put_task_struct(c);
                 goto retry;
         }
-        cgroup_mm_owner_callbacks(mm->owner, c);
         mm->owner = c;
         task_unlock(c);
-        up_write(&mm->mmap_sem);
         put_task_struct(c);
 }
 #endif /* CONFIG_MM_OWNER */
@@ -973,12 +980,9 @@ 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);
+        free = stack_not_used(current);
 
         if (free >= lowest_to_date)
                 return;
@@ -1029,8 +1033,6 @@ NORET_TYPE void do_exit(long code)
                  * 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();
         }
@@ -1049,24 +1051,13 @@ NORET_TYPE void do_exit(long code)
                                 preempt_count());
 
         acct_update_integrals(tsk);
-        if (tsk->mm) {
-                update_hiwater_rss(tsk->mm);
-                update_hiwater_vm(tsk->mm);
-        }
+
         group_dead = atomic_dec_and_test(&tsk->signal->live);
         if (group_dead) {
                 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);
-#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))
@@ -1087,7 +1078,6 @@ NORET_TYPE void do_exit(long code)
         check_stack_usage();
         exit_thread();
         cgroup_exit(tsk, 1);
-        exit_keys(tsk);
 
         if (group_dead && tsk->signal->leader)
                 disassociate_ctty(1);
@@ -1132,7 +1122,6 @@ NORET_TYPE void do_exit(long code)
         preempt_disable();
         /* causes final put_task_struct in finish_task_switch(). */
         tsk->state = TASK_DEAD;
-
         schedule();
         BUG();
         /* Avoid "noreturn function does return".  */
@@ -1152,7 +1141,7 @@ NORET_TYPE void complete_and_exit(struct completion *comp, long code)
 
 EXPORT_SYMBOL(complete_and_exit);
 
-asmlinkage long sys_exit(int error_code)
+SYSCALL_DEFINE1(exit, int, error_code)
 {
         do_exit((error_code&0xff)<<8);
 }
@@ -1193,9 +1182,11 @@ do_group_exit(int exit_code)
  * 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)
+SYSCALL_DEFINE1(exit_group, int, error_code)
 {
         do_group_exit((error_code & 0xff) << 8);
+        /* NOTREACHED */
+        return 0;
 }
 
 static struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
@@ -1272,12 +1263,12 @@ static int wait_task_zombie(struct task_struct *p, int options,
         unsigned long state;
         int retval, status, traced;
         pid_t pid = task_pid_vnr(p);
+        uid_t uid = __task_cred(p)->uid;
 
         if (!likely(options & WEXITED))
                 return 0;
 
         if (unlikely(options & WNOWAIT)) {
-                uid_t uid = p->uid;
                 int exit_code = p->exit_code;
                 int why, status;
 
@@ -1330,10 +1321,10 @@ static int wait_task_zombie(struct task_struct *p, int options,
                  * 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;
                 sig = p->signal;
-                thread_group_cputime(p, &cputime);
                 psig->cutime =
                         cputime_add(psig->cutime,
                         cputime_add(cputime.utime,
@@ -1398,7 +1389,7 @@ static int wait_task_zombie(struct task_struct *p, int options,
         if (!retval && infop)
                 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 = pid;
 
@@ -1463,7 +1454,8 @@ static int wait_task_stopped(int ptrace, struct task_struct *p,
         if (!unlikely(options & WNOWAIT))
                 p->exit_code = 0;
 
-        uid = p->uid;
+        /* don't need the RCU readlock here as we're holding a spinlock */
+        uid = __task_cred(p)->uid;
 unlock_sig:
         spin_unlock_irq(&p->sighand->siglock);
         if (!exit_code)
@@ -1537,10 +1529,10 @@ static int wait_task_continued(struct task_struct *p, int options,
         }
         if (!unlikely(options & WNOWAIT))
                 p->signal->flags &= ~SIGNAL_STOP_CONTINUED;
+        uid = __task_cred(p)->uid;
         spin_unlock_irq(&p->sighand->siglock);
 
         pid = task_pid_vnr(p);
-        uid = p->uid;
         get_task_struct(p);
         read_unlock(&tasklist_lock);
 
@@ -1762,9 +1754,8 @@ end:
         return retval;
 }
 
-asmlinkage long sys_waitid(int which, pid_t upid,
-                           struct siginfo __user *infop, int options,
-                           struct rusage __user *ru)
+SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
+                infop, int, options, struct rusage __user *, ru)
 {
         struct pid *pid = NULL;
         enum pid_type type;
@@ -1803,8 +1794,8 @@ asmlinkage long sys_waitid(int which, pid_t upid,
         return ret;
 }
 
-asmlinkage long sys_wait4(pid_t upid, int __user *stat_addr,
-                          int options, struct rusage __user *ru)
+SYSCALL_DEFINE4(wait4, pid_t, upid, int __user *, stat_addr,
+                int, options, struct rusage __user *, ru)
 {
         struct pid *pid = NULL;
         enum pid_type type;
@@ -1841,7 +1832,7 @@ asmlinkage long sys_wait4(pid_t upid, int __user *stat_addr,
  * 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)
+SYSCALL_DEFINE3(waitpid, pid_t, pid, int __user *, stat_addr, int, options)
 {
         return sys_wait4(pid, stat_addr, options, NULL);
 }