Re: [PATCH -mmotm v2] mm: fix kmemcheck.c build errors

[Randy Dunlap <rdunlap@infradead.org>]

On 08/31/14 17:13, Joonsoo Kim wrote:
> On Sun, Aug 31, 2014 at 04:33:12PM -0700, Randy Dunlap wrote:
>> On 08/31/14 07:48, Randy Dunlap wrote:
>>> On 08/31/14 04:36, Andrey Ryabinin wrote:
>>>> 2014-08-30 5:48 GMT+04:00 Randy Dunlap <rdunlap@infradead.org>:
>>>>> From: Randy Dunlap <rdunlap@infradead.org>
>>>>>
>>>>> Add header file to fix kmemcheck.c build errors:
>>>>>
>>>>> ../mm/kmemcheck.c:70:7: error: dereferencing pointer to incomplete type
>>>>> ../mm/kmemcheck.c:83:15: error: dereferencing pointer to incomplete type
>>>>> ../mm/kmemcheck.c:95:8: error: dereferencing pointer to incomplete type
>>>>> ../mm/kmemcheck.c:95:21: error: dereferencing pointer to incomplete type
>>>>>
>>>>> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
>>>>> ---
>>>>>  mm/kmemcheck.c |    1 +
>>>>>  1 file changed, 1 insertion(+)
>>>>>
>>>>> Index: mmotm-2014-0829-1515/mm/kmemcheck.c
>>>>> ===================================================================
>>>>> --- mmotm-2014-0829-1515.orig/mm/kmemcheck.c
>>>>> +++ mmotm-2014-0829-1515/mm/kmemcheck.c
>>>>> @@ -2,6 +2,7 @@
>>>>>  #include <linux/mm_types.h>
>>>>>  #include <linux/mm.h>
>>>>>  #include <linux/slab.h>
>>>>> +#include <linux/slab_def.h>
>>>>
>>>> This will work only for CONFIG_SLAB=y. struct kmem_cache definition
>>>> was moved to internal header [*],
>>>> so you need to include it here:
>>>> #include "slab.h"
>>>>
>>>> [*] http://ozlabs.org/~akpm/mmotm/broken-out/mm-slab_common-move-kmem_cache-definition-to-internal-header.patch
>>>
>>> Thanks.  That makes sense.  [testing]  mm/kmemcheck.c still has a build error:
>>>
>>> In file included from ../mm/kmemcheck.c:5:0:
>>> ../mm/slab.h: In function 'cache_from_obj':
>>> ../mm/slab.h:283:2: error: implicit declaration of function 'memcg_kmem_enabled' [-Werror=implicit-function-declaration]
>>>
>>
>> Naughty header file.  It uses something from <linux/memcontrol.h> without
>> #including that header file...
> 
> 
> Hello.
> 
> Indeed...
> Thanks for catching this.
> 
>>
>> Working patch is below.
> 
> With your patch, build also failed if CONFIG_MEMCG_KMEM=y.
> Right fix is something like below.
> 
> Thanks.
> 
> --------->8----------
> diff --git a/mm/kmemcheck.c b/mm/kmemcheck.c
> index fd814fd..cab58bb 100644
> --- a/mm/kmemcheck.c
> +++ b/mm/kmemcheck.c
> @@ -2,6 +2,7 @@
>  #include <linux/mm_types.h>
>  #include <linux/mm.h>
>  #include <linux/slab.h>
> +#include "slab.h"
>  #include <linux/kmemcheck.h>
>  
>  void kmemcheck_alloc_shadow(struct page *page, int order, gfp_t flags, int node)
> diff --git a/mm/slab.h b/mm/slab.h
> index 13845d0..963a3f8 100644
> --- a/mm/slab.h
> +++ b/mm/slab.h
> @@ -37,6 +37,8 @@ struct kmem_cache {
>  #include <linux/slub_def.h>
>  #endif
>  
> +#include <linux/memcontrol.h>
> +
>  /*
>   * State of the slab allocator.
>   *
> --

Um, yeah, looks equivalent to what I sent as v2.

Thanks.

-- 
~Randy