diff options
Diffstat (limited to 'kernel/sys.c')
-rw-r--r-- | kernel/sys.c | 13 |
1 files changed, 1 insertions, 12 deletions
diff --git a/kernel/sys.c b/kernel/sys.c index 84371fdc660b..7ef7f6054c28 100644 --- a/kernel/sys.c +++ b/kernel/sys.c | |||
@@ -1206,7 +1206,7 @@ asmlinkage long sys_times(struct tms __user * tbuf) | |||
1206 | struct task_struct *t; | 1206 | struct task_struct *t; |
1207 | cputime_t utime, stime, cutime, cstime; | 1207 | cputime_t utime, stime, cutime, cstime; |
1208 | 1208 | ||
1209 | read_lock(&tasklist_lock); | 1209 | spin_lock_irq(&tsk->sighand->siglock); |
1210 | utime = tsk->signal->utime; | 1210 | utime = tsk->signal->utime; |
1211 | stime = tsk->signal->stime; | 1211 | stime = tsk->signal->stime; |
1212 | t = tsk; | 1212 | t = tsk; |
@@ -1216,20 +1216,9 @@ asmlinkage long sys_times(struct tms __user * tbuf) | |||
1216 | t = next_thread(t); | 1216 | t = next_thread(t); |
1217 | } while (t != tsk); | 1217 | } while (t != tsk); |
1218 | 1218 | ||
1219 | /* | ||
1220 | * While we have tasklist_lock read-locked, no dying thread | ||
1221 | * can be updating current->signal->[us]time. Instead, | ||
1222 | * we got their counts included in the live thread loop. | ||
1223 | * However, another thread can come in right now and | ||
1224 | * do a wait call that updates current->signal->c[us]time. | ||
1225 | * To make sure we always see that pair updated atomically, | ||
1226 | * we take the siglock around fetching them. | ||
1227 | */ | ||
1228 | spin_lock_irq(&tsk->sighand->siglock); | ||
1229 | cutime = tsk->signal->cutime; | 1219 | cutime = tsk->signal->cutime; |
1230 | cstime = tsk->signal->cstime; | 1220 | cstime = tsk->signal->cstime; |
1231 | spin_unlock_irq(&tsk->sighand->siglock); | 1221 | spin_unlock_irq(&tsk->sighand->siglock); |
1232 | read_unlock(&tasklist_lock); | ||
1233 | 1222 | ||
1234 | tmp.tms_utime = cputime_to_clock_t(utime); | 1223 | tmp.tms_utime = cputime_to_clock_t(utime); |
1235 | tmp.tms_stime = cputime_to_clock_t(stime); | 1224 | tmp.tms_stime = cputime_to_clock_t(stime); |