leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

sched: Add debug check to task_of()

Browse Source 
A frequent mistake appears to be to call task_of() on a
scheduler entity that is not actually a task, which can result
in a wild pointer.

Add a check to catch these mistakes.

Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-07-24 12:25:30 +02:00 committed by Ingo Molnar
parent 00aec93d10
commit 8f48894fcc
2 changed files with 27 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
kernel/sched_fair.c
View File

@ -79,11 +79,6 @@ static const struct sched_class fair_sched_class;
* CFS operations on generic schedulable entities:
*/
static inline struct task_struct *task_of(struct sched_entity *se)
{
return container_of(se, struct task_struct, se);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
/* cpu runqueue to which this cfs_rq is attached */
@ -95,6 +90,14 @@ static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
/* An entity is a task if it doesn't "own" a runqueue */
#define entity_is_task(se) (!se->my_q)
static inline struct task_struct *task_of(struct sched_entity *se)
{
#ifdef CONFIG_SCHED_DEBUG
WARN_ON_ONCE(!entity_is_task(se));
#endif
return container_of(se, struct task_struct, se);
}
/* Walk up scheduling entities hierarchy */
#define for_each_sched_entity(se) \
for (; se; se = se->parent)
@ -186,7 +189,12 @@ find_matching_se(struct sched_entity **se, struct sched_entity **pse)
}
}
#else /* CONFIG_FAIR_GROUP_SCHED */
#else /* !CONFIG_FAIR_GROUP_SCHED */
static inline struct task_struct *task_of(struct sched_entity *se)
{
return container_of(se, struct task_struct, se);
}
static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
{

18
kernel/sched_rt.c
View File

@ -3,15 +3,18 @@
* policies)
*/
static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
{
return container_of(rt_se, struct task_struct, rt);
}
#ifdef CONFIG_RT_GROUP_SCHED
#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
{
#ifdef CONFIG_SCHED_DEBUG
WARN_ON_ONCE(!rt_entity_is_task(rt_se));
#endif
return container_of(rt_se, struct task_struct, rt);
}
static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
{
return rt_rq->rq;
@ -26,6 +29,11 @@ static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
#define rt_entity_is_task(rt_se) (1)
static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
{
return container_of(rt_se, struct task_struct, rt);
}
static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
{
return container_of(rt_rq, struct rq, rt);