diff options
| author | Christoph Lameter <cl@linux.com> | 2011-07-06 09:46:18 -0500 |
|---|---|---|
| committer | Pekka Enberg <penberg@kernel.org> | 2011-07-07 22:24:30 +0300 |
| commit | ea6bd8ee1a2ccdffc38b2b1fcfe941addfafaade (patch) | |
| tree | d8f98147ed392a6b49d89f6cfe5885b059a58538 /include/linux/mm_types.h | |
| parent | 9da4714a2d44ff48618a8d375dd81873e858803d (diff) | |
SLUB: Fix build breakage in linux/mm_types.h
On Wed, 6 Jul 2011, Jonathan Cameron wrote:
> Getting:
>
> CHK include/linux/version.h
> CHK include/generated/utsrelease.h
> make[1]: `include/generated/mach-types.h' is up to date.
> CC arch/arm/kernel/asm-offsets.s
> In file included from include/linux/sched.h:64:0,
> from arch/arm/kernel/asm-offsets.c:13:
> include/linux/mm_types.h:74:15: error: duplicate member '_count'
> make[1]: *** [arch/arm/kernel/asm-offsets.s] Error 1
> make: *** [prepare0] Error 2
>
> Issue looks to have been introduced by
>
> mm: Rearrange struct page
>
> fc9bb8c768abe7ae10861c3510e01a95f98d5933
>
> Guessing it's a known issue, but just thought I'd flag it up in case
> it's something very specific about my build.
>
> gcc-2.6 armv7a
>
> Reverting that patch works, but given I don't know the history, I'm
> not proposing doing that in general!
Well _count exists in two unionized structs but always has the same offset
within the larger struct. Maybe ARM creates different offsets there for
some reason?
The following is a patch to restructure the union / structs combo in such
a way that only a single definition of _count
Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Tested-by: Piotr Hosowicz <piotr@hosowicz.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Diffstat (limited to 'include/linux/mm_types.h')
| -rw-r--r-- | include/linux/mm_types.h | 25 |
1 files changed, 10 insertions, 15 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3d76a433d52..6dc6413f5de 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -49,32 +49,27 @@ struct page { * see PAGE_MAPPING_ANON below. */ /* Second double word */ - union { - struct { + struct { + union { pgoff_t index; /* Our offset within mapping. */ + void *freelist; /* slub first free object */ + }; + + union { atomic_t _mapcount; /* Count of ptes mapped in mms, * to show when page is mapped * & limit reverse map searches. */ - atomic_t _count; /* Usage count, see below. */ - }; - struct { /* SLUB cmpxchg_double area */ - void *freelist; - union { - unsigned long counters; - struct { + /* Used for cmpxchg_double in slub */ + unsigned long counters; + struct { unsigned inuse:16; unsigned objects:15; unsigned frozen:1; - /* - * Kernel may make use of this field even when slub - * uses the rest of the double word! - */ - atomic_t _count; - }; }; }; + atomic_t _count; /* Usage count, see below. */ }; /* Third double word block */ |