bianbu-repo-mirror/bianbu-linux-6.6
1
0
Fork 0
mirror of https://gitee.com/bianbu-linux/linux-6.6 synced 2025-04-24 14:07:52 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

tasks: Add a count of task RCU users

Browse source 
Add a count of the number of RCU users (currently 1) of the task
struct so that we can later add the scheduler case and get rid of the
very subtle task_rcu_dereference(), and just use rcu_dereference().

As suggested by Oleg have the count overlap rcu_head so that no
additional space in task_struct is required.

Inspired-by: Linus Torvalds <torvalds@linux-foundation.org>
Inspired-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87woebdplt.fsf_-_@x220.int.ebiederm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Eric W. Biederman 2019-09-14 07:33:34 -05:00 • committed by Ingo Molnar
parent 42fd8baab3
commit 3fbd7ee285
4 changed files with 14 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

1
include/linux/sched/task.h
View file

@ -120,6 +120,7 @@ static inline void put_task_struct(struct task_struct *t)
}
struct task_struct *task_rcu_dereference(struct task_struct **ptask);
void put_task_struct_rcu_user(struct task_struct *task);
#ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
extern int arch_task_struct_size __read_mostly;