[PATCH] cgroup: explicitly init the early_init field

[PATCH] cgroup: explicitly init the early_init field

[Jianyu Zhan]

For a cgroup subsystem who should init early, then it should carefully
take care of the implementation of css_alloc, because it will be called
before mm_init() setup the world.

Luckily we don't, and we better explicitly assign the early_init field
to 0, for document reason.

Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
---
 kernel/cgroup.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 559f822..f23cb67 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5325,5 +5325,6 @@ struct cgroup_subsys debug_cgrp_subsys = {
 	.css_alloc = debug_css_alloc,
 	.css_free = debug_css_free,
 	.base_cftypes = debug_files,
+	.early_init = 0,
 };
 #endif /* CONFIG_CGROUP_DEBUG */
-- 
2.0.0-rc0

Re: [PATCH] cgroup: explicitly init the early_init field

[Li Zefan]

On 2014/4/22 13:27, Jianyu Zhan wrote:
> For a cgroup subsystem who should init early, then it should carefully
> take care of the implementation of css_alloc, because it will be called
> before mm_init() setup the world.
> 
> Luckily we don't, and we better explicitly assign the early_init field
> to 0, for document reason.
> 

If you think this is the right thing to do, you can apply the same reason
to the initialization of other structures in the whole kernel tree.

> Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>

nack

> ---
>  kernel/cgroup.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index 559f822..f23cb67 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> @@ -5325,5 +5325,6 @@ struct cgroup_subsys debug_cgrp_subsys = {
>  	.css_alloc = debug_css_alloc,
>  	.css_free = debug_css_free,
>  	.base_cftypes = debug_files,
> +	.early_init = 0,
>  };
>  #endif /* CONFIG_CGROUP_DEBUG */
> 

Re: [PATCH] cgroup: explicitly init the early_init field

[Jianyu Zhan]

On Tue, Apr 22, 2014 at 2:22 PM, Li Zefan <lizefan@huawei.com> wrote:
> If you think this is the right thing to do, you can apply the same reason
> to the initialization of other structures in the whole kernel tree.
>
>> Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
>
> nack

Hi, Li,

Sorry for the noise.

For cpuset subsystem, this filed is nonzero; for other subsystems, this is zero.
Actually none of these subsystem will change this field,  I just
thought that  this is a little subtle. as the comment in patches says,
this is mainly for
document reason to inform other maintainers that css_alloc
implementation should be
taken care of , depending on this field is zero or not.


Thanks,
Jianyu Zhan