diff options
author | Avi Kivity <avi@qumranet.com> | 2007-07-26 13:40:43 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2007-07-26 13:40:43 +0200 |
commit | e107be36efb2a233833e8c9899039a370e4b2318 (patch) | |
tree | 655955aa81aefeff441c412adaafe9b51a00ff56 /include | |
parent | b47e8608a08766ef8121cd747d3aaf6c3dc22649 (diff) | |
download | op-kernel-dev-e107be36efb2a233833e8c9899039a370e4b2318.zip op-kernel-dev-e107be36efb2a233833e8c9899039a370e4b2318.tar.gz |
[PATCH] sched: arch preempt notifier mechanism
This adds a general mechanism whereby a task can request the scheduler to
notify it whenever it is preempted or scheduled back in. This allows the
task to swap any special-purpose registers like the fpu or Intel's VT
registers.
Signed-off-by: Avi Kivity <avi@qumranet.com>
[ mingo@elte.hu: fixes, cleanups ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/preempt.h | 44 | ||||
-rw-r--r-- | include/linux/sched.h | 5 |
2 files changed, 49 insertions, 0 deletions
diff --git a/include/linux/preempt.h b/include/linux/preempt.h index d0926d6..484988e 100644 --- a/include/linux/preempt.h +++ b/include/linux/preempt.h @@ -8,6 +8,7 @@ #include <linux/thread_info.h> #include <linux/linkage.h> +#include <linux/list.h> #ifdef CONFIG_DEBUG_PREEMPT extern void fastcall add_preempt_count(int val); @@ -60,4 +61,47 @@ do { \ #endif +#ifdef CONFIG_PREEMPT_NOTIFIERS + +struct preempt_notifier; + +/** + * preempt_ops - notifiers called when a task is preempted and rescheduled + * @sched_in: we're about to be rescheduled: + * notifier: struct preempt_notifier for the task being scheduled + * cpu: cpu we're scheduled on + * @sched_out: we've just been preempted + * notifier: struct preempt_notifier for the task being preempted + * next: the task that's kicking us out + */ +struct preempt_ops { + void (*sched_in)(struct preempt_notifier *notifier, int cpu); + void (*sched_out)(struct preempt_notifier *notifier, + struct task_struct *next); +}; + +/** + * preempt_notifier - key for installing preemption notifiers + * @link: internal use + * @ops: defines the notifier functions to be called + * + * Usually used in conjunction with container_of(). + */ +struct preempt_notifier { + struct hlist_node link; + struct preempt_ops *ops; +}; + +void preempt_notifier_register(struct preempt_notifier *notifier); +void preempt_notifier_unregister(struct preempt_notifier *notifier); + +static inline void preempt_notifier_init(struct preempt_notifier *notifier, + struct preempt_ops *ops) +{ + INIT_HLIST_NODE(¬ifier->link); + notifier->ops = ops; +} + +#endif + #endif /* __LINUX_PREEMPT_H */ diff --git a/include/linux/sched.h b/include/linux/sched.h index 7c61b50..7a4de87 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -935,6 +935,11 @@ struct task_struct { struct sched_class *sched_class; struct sched_entity se; +#ifdef CONFIG_PREEMPT_NOTIFIERS + /* list of struct preempt_notifier: */ + struct hlist_head preempt_notifiers; +#endif + unsigned short ioprio; #ifdef CONFIG_BLK_DEV_IO_TRACE unsigned int btrace_seq; |