Re: [PATCH cgroup/for-3.11 3/3] cgroup: always use RCU accessors for protected accesses

[Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2013/6/22 6:52, Tejun Heo wrote:
> kernel/cgroup.c still has places where a RCU pointer is set and
> accessed directly without going through RCU_INIT_POINTER() or
> rcu_dereference_protected().  They're all properly protected accesses
> so nothing is broken but it leads to spurious sparse RCU address space
> warnings.
> 
> Substitute direct accesses with RCU_INIT_POINTER() and
> rcu_dereference_protected().  Note that %true is specified as the
> extra condition for all derference updates.  This isn't ideal as all
> it does is suppressing warning without actually policing
> synchronization rules; however, most are scheduled to be removed
> pretty soon along with css_id itself, so no reason to be more
> elaborate.
> 
> Combined with the previous changes, this removes all RCU related
> sparse warnings from cgroup.
> 
> Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Reported-by: Fengguang Wu <fengguang.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> ---
>  kernel/cgroup.c |   21 ++++++++++++---------
>  1 file changed, 12 insertions(+), 9 deletions(-)
> 

Acked-by; Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>