Revert "kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function"

This reverts commit 23196f2e5f.

Now that struct kthread is kmalloc'ed and not longer on the task stack
there is no need anymore to pin the stack.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chunming Zhou <David1.Zhou@amd.com>
Cc: Roman Pen <roman.penyaev@profitbricks.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20161129175100.GA5333@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Oleg Nesterov 2016-11-29 18:51:00 +01:00 committed by Thomas Gleixner
parent 1da5c46fa9
commit eff9662547

View File

@ -88,7 +88,7 @@ void free_kthread_struct(struct task_struct *k)
static struct kthread *to_live_kthread(struct task_struct *k)
{
struct completion *vfork = ACCESS_ONCE(k->vfork_done);
if (likely(vfork) && try_get_task_stack(k))
if (likely(vfork))
return __to_kthread(vfork);
return NULL;
}
@ -473,10 +473,8 @@ void kthread_unpark(struct task_struct *k)
{
struct kthread *kthread = to_live_kthread(k);
if (kthread) {
if (kthread)
__kthread_unpark(k, kthread);
put_task_stack(k);
}
}
EXPORT_SYMBOL_GPL(kthread_unpark);
@ -505,7 +503,6 @@ int kthread_park(struct task_struct *k)
wait_for_completion(&kthread->parked);
}
}
put_task_stack(k);
ret = 0;
}
return ret;
@ -541,7 +538,6 @@ int kthread_stop(struct task_struct *k)
__kthread_unpark(k, kthread);
wake_up_process(k);
wait_for_completion(&kthread->exited);
put_task_stack(k);
}
ret = k->exit_code;
put_task_struct(k);