On 06/25, Jiri Slaby wrote: > > From: Oleg Nesterov <[email protected]> > > This patch has been added to the 3.12 stable tree. If you have any > objections, please let us know.
Well, this patch should not hurt, but why? It was a minor cleanup to improve the "scheduling while atomic" detection. > =============== > > commit 192301e70af3f6803c6354a464ebfa742da738ae upstream. > > schedule_debug() ignores in_atomic() if prev->exit_state != 0. > This is not what we want, ->exit_state is set by exit_notify() > but we should complain until the task does the last schedule() > in TASK_DEAD. > > See also 7407251a0e2e "PF_DEAD cleanup", I think this ancient > commit explains why schedule() had to rely on ->exit_state, > until that commit exit_notify() disabled preemption and set > PF_DEAD which was used to detect the exiting task. > > Signed-off-by: Oleg Nesterov <[email protected]> > Signed-off-by: Peter Zijlstra <[email protected]> > Cc: David Laight <[email protected]> > Cc: Geert Uytterhoeven <[email protected]> > Cc: Tejun Heo <[email protected]> > Cc: Andrew Morton <[email protected]> > Cc: Linus Torvalds <[email protected]> > Link: http://lkml.kernel.org/r/[email protected] > Signed-off-by: Ingo Molnar <[email protected]> > Signed-off-by: Jiri Slaby <[email protected]> > --- > kernel/sched/core.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 07039cba59d9..58a54f219c8f 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -2287,10 +2287,10 @@ static inline void schedule_debug(struct task_struct > *prev) > { > /* > * Test if we are atomic. Since do_exit() needs to call into > - * schedule() atomically, we ignore that path for now. > - * Otherwise, whine if we are scheduling when we should not be. > + * schedule() atomically, we ignore that path. Otherwise whine > + * if we are scheduling when we should not. > */ > - if (unlikely(in_atomic_preempt_off() && !prev->exit_state)) > + if (unlikely(in_atomic_preempt_off() && prev->state != TASK_DEAD)) > __schedule_bug(prev); > rcu_sleep_check(); > > -- > 2.0.0 > -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
