mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-21 11:44:01 +08:00
6cc88bc45c
Rename is_single_threaded() to is_wq_single_threaded() so that a new is_single_threaded() can be created that refers to tasks rather than waitqueues. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <jmorris@namei.org> Signed-off-by: James Morris <jmorris@namei.org>
46 lines
1.2 KiB
C
46 lines
1.2 KiB
C
/* Function to determine if a thread group is single threaded or not
|
|
*
|
|
* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
* - Derived from security/selinux/hooks.c
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
|
|
/**
|
|
* is_single_threaded - Determine if a thread group is single-threaded or not
|
|
* @p: A task in the thread group in question
|
|
*
|
|
* This returns true if the thread group to which a task belongs is single
|
|
* threaded, false if it is not.
|
|
*/
|
|
bool is_single_threaded(struct task_struct *p)
|
|
{
|
|
struct task_struct *g, *t;
|
|
struct mm_struct *mm = p->mm;
|
|
|
|
if (atomic_read(&p->signal->count) != 1)
|
|
goto no;
|
|
|
|
if (atomic_read(&p->mm->mm_users) != 1) {
|
|
read_lock(&tasklist_lock);
|
|
do_each_thread(g, t) {
|
|
if (t->mm == mm && t != p)
|
|
goto no_unlock;
|
|
} while_each_thread(g, t);
|
|
read_unlock(&tasklist_lock);
|
|
}
|
|
|
|
return true;
|
|
|
|
no_unlock:
|
|
read_unlock(&tasklist_lock);
|
|
no:
|
|
return false;
|
|
}
|