aboutsummaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2007-12-04 11:04:39 -0500
committerIngo Molnar <mingo@elte.hu>2007-12-04 11:04:39 -0500
commit77034937dc4575ca0a76bf209838ecd39e804089 (patch)
tree96713ca12264ead56f859fd3619b27e49072456a /kernel
parent09b56adc98e0f8a21644fcb4d20ad367c3fceb55 (diff)
sched: fix crash in sys_sched_rr_get_interval()
Luiz Fernando N. Capitulino reported that sched_rr_get_interval() crashes for SCHED_OTHER tasks that are on an idle runqueue. The fix is to return a 0 timeslice for tasks that are on an idle runqueue. (and which are not running, obviously) this also shrinks the code a bit: text data bss dec hex filename 47903 3934 336 52173 cbcd sched.o.before 47885 3934 336 52155 cbbb sched.o.after Reported-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched.c14
1 files changed, 9 insertions, 5 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 59ff6b140edb..b062856b946c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4850,17 +4850,21 @@ long sys_sched_rr_get_interval(pid_t pid, struct timespec __user *interval)
4850 if (retval) 4850 if (retval)
4851 goto out_unlock; 4851 goto out_unlock;
4852 4852
4853 if (p->policy == SCHED_FIFO) 4853 /*
4854 time_slice = 0; 4854 * Time slice is 0 for SCHED_FIFO tasks and for SCHED_OTHER
4855 else if (p->policy == SCHED_RR) 4855 * tasks that are on an otherwise idle runqueue:
4856 */
4857 time_slice = 0;
4858 if (p->policy == SCHED_RR) {
4856 time_slice = DEF_TIMESLICE; 4859 time_slice = DEF_TIMESLICE;
4857 else { 4860 } else {
4858 struct sched_entity *se = &p->se; 4861 struct sched_entity *se = &p->se;
4859 unsigned long flags; 4862 unsigned long flags;
4860 struct rq *rq; 4863 struct rq *rq;
4861 4864
4862 rq = task_rq_lock(p, &flags); 4865 rq = task_rq_lock(p, &flags);
4863 time_slice = NS_TO_JIFFIES(sched_slice(cfs_rq_of(se), se)); 4866 if (rq->cfs.load.weight)
4867 time_slice = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
4864 task_rq_unlock(rq, &flags); 4868 task_rq_unlock(rq, &flags);
4865 } 4869 }
4866 read_unlock(&tasklist_lock); 4870 read_unlock(&tasklist_lock);