From 85ba2d862e521375a8ee01526c5c46b1f24bb4af Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Fri, 25 Jul 2008 19:45:58 -0700 Subject: tracehook: wait_task_inactive This extends wait_task_inactive() with a new argument so it can be used in a "soft" mode where it will check for the task changing state unexpectedly and back off. There is no change to existing callers. This lays the groundwork to allow robust, noninvasive tracing that can try to sample a blocked thread but back off safely if it wakes up. Signed-off-by: Roland McGrath Cc: Oleg Nesterov Reviewed-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/sched.h b/include/linux/sched.h index a95d84d0da9..f59318a0099 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1882,9 +1882,13 @@ extern void set_task_comm(struct task_struct *tsk, char *from); extern char *get_task_comm(char *to, struct task_struct *tsk); #ifdef CONFIG_SMP -extern void wait_task_inactive(struct task_struct * p); +extern unsigned long wait_task_inactive(struct task_struct *, long match_state); #else -#define wait_task_inactive(p) do { } while (0) +static inline unsigned long wait_task_inactive(struct task_struct *p, + long match_state) +{ + return 1; +} #endif #define next_task(p) list_entry(rcu_dereference((p)->tasks.next), struct task_struct, tasks) -- cgit v1.2.3-18-g5258