1 files changed, 22 insertions, 23 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index ce17760d9c5..26a6b73a6b8 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -8,7 +8,6 @@
 #include <linux/mm.h>
 #include <linux/utsname.h>
 #include <linux/mman.h>
-#include <linux/smp_lock.h>
 #include <linux/notifier.h>
 #include <linux/reboot.h>
 #include <linux/prctl.h>
@@ -163,6 +162,7 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
 	if (niceval > 19)
 		niceval = 19;
 
+	rcu_read_lock();
 	read_lock(&tasklist_lock);
 	switch (which) {
 		case PRIO_PROCESS:
@@ -190,16 +190,17 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
 				 !(user = find_user(who)))
 				goto out_unlock;	/* No processes for this user */
 
-			do_each_thread(g, p)
+			do_each_thread(g, p) {
 				if (__task_cred(p)->uid == who)
 					error = set_one_prio(p, niceval, error);
-			while_each_thread(g, p);
+			} while_each_thread(g, p);
 			if (who != cred->uid)
 				free_uid(user);		/* For find_user() */
 			break;
 	}
 out_unlock:
 	read_unlock(&tasklist_lock);
+	rcu_read_unlock();
 out:
 	return error;
 }
@@ -253,13 +254,13 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
 				 !(user = find_user(who)))
 				goto out_unlock;	/* No processes for this user */
 
-			do_each_thread(g, p)
+			do_each_thread(g, p) {
 				if (__task_cred(p)->uid == who) {
 					niceval = 20 - task_nice(p);
 					if (niceval > retval)
 						retval = niceval;
 				}
-			while_each_thread(g, p);
+			} while_each_thread(g, p);
 			if (who != cred->uid)
 				free_uid(user);		/* for find_user() */
 			break;
@@ -349,6 +350,9 @@ void kernel_power_off(void)
 	machine_power_off();
 }
 EXPORT_SYMBOL_GPL(kernel_power_off);
+
+static DEFINE_MUTEX(reboot_mutex);
+
 /*
  * Reboot system call: for obvious reasons only root may call it,
  * and even root needs to set up some magic numbers in the registers
@@ -381,7 +385,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
 	if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
 		cmd = LINUX_REBOOT_CMD_HALT;
 
-	lock_kernel();
+	mutex_lock(&reboot_mutex);
 	switch (cmd) {
 	case LINUX_REBOOT_CMD_RESTART:
 		kernel_restart(NULL);
@@ -397,20 +401,18 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
 
 	case LINUX_REBOOT_CMD_HALT:
 		kernel_halt();
-		unlock_kernel();
 		do_exit(0);
 		panic("cannot halt");
 
 	case LINUX_REBOOT_CMD_POWER_OFF:
 		kernel_power_off();
-		unlock_kernel();
 		do_exit(0);
 		break;
 
 	case LINUX_REBOOT_CMD_RESTART2:
 		if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
-			unlock_kernel();
-			return -EFAULT;
+			ret = -EFAULT;
+			break;
 		}
 		buffer[sizeof(buffer) - 1] = '\0';
 
@@ -433,7 +435,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
 		ret = -EINVAL;
 		break;
 	}
-	unlock_kernel();
+	mutex_unlock(&reboot_mutex);
 	return ret;
 }
 
@@ -911,16 +913,15 @@ change_okay:
 
 void do_sys_times(struct tms *tms)
 {
-	struct task_cputime cputime;
-	cputime_t cutime, cstime;
+	cputime_t tgutime, tgstime, cutime, cstime;
 
-	thread_group_cputime(current, &cputime);
 	spin_lock_irq(&current->sighand->siglock);
+	thread_group_times(current, &tgutime, &tgstime);
 	cutime = current->signal->cutime;
 	cstime = current->signal->cstime;
 	spin_unlock_irq(&current->sighand->siglock);
-	tms->tms_utime = cputime_to_clock_t(cputime.utime);
-	tms->tms_stime = cputime_to_clock_t(cputime.stime);
+	tms->tms_utime = cputime_to_clock_t(tgutime);
+	tms->tms_stime = cputime_to_clock_t(tgstime);
 	tms->tms_cutime = cputime_to_clock_t(cutime);
 	tms->tms_cstime = cputime_to_clock_t(cstime);
 }
@@ -1338,16 +1339,14 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 {
 	struct task_struct *t;
 	unsigned long flags;
-	cputime_t utime, stime;
-	struct task_cputime cputime;
+	cputime_t tgutime, tgstime, utime, stime;
 	unsigned long maxrss = 0;
 
 	memset((char *) r, 0, sizeof *r);
 	utime = stime = cputime_zero;
 
 	if (who == RUSAGE_THREAD) {
-		utime = task_utime(current);
-		stime = task_stime(current);
+		task_times(current, &utime, &stime);
 		accumulate_thread_rusage(p, r);
 		maxrss = p->signal->maxrss;
 		goto out;
@@ -1373,9 +1372,9 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 				break;
 
 		case RUSAGE_SELF:
-			thread_group_cputime(p, &cputime);
-			utime = cputime_add(utime, cputime.utime);
-			stime = cputime_add(stime, cputime.stime);
+			thread_group_times(p, &tgutime, &tgstime);
+			utime = cputime_add(utime, tgutime);
+			stime = cputime_add(stime, tgstime);
 			r->ru_nvcsw += p->signal->nvcsw;
 			r->ru_nivcsw += p->signal->nivcsw;
 			r->ru_minflt += p->signal->min_flt;