diff options
| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2009-08-31 14:43:35 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-08-31 18:08:49 +0200 |
| commit | 0ee000e5e8fa2e5c760250be0d78d5906e3eb94b (patch) | |
| tree | 7c3d253b2e6d89bdae8c1fbe86baa17b080efcce /arch/m68k/include | |
| parent | f159ee782990aacb5494738c98f13a2aa61dbb4a (diff) | |
| download | kernel_samsung_smdk4412-0ee000e5e8fa2e5c760250be0d78d5906e3eb94b.tar.gz kernel_samsung_smdk4412-0ee000e5e8fa2e5c760250be0d78d5906e3eb94b.tar.bz2 kernel_samsung_smdk4412-0ee000e5e8fa2e5c760250be0d78d5906e3eb94b.zip | |
locking, m68k: Calculate thread_info offset with asm offset
m68k has the thread_info structure embedded in its task struct.
Therefore its not possible to implement current_thread_info()
by looking at the stack pointer and do some simple calculations
like most other architectures do it.
To return the thread_info pointer for a task two defines are
used. This works until the spinlock function bodies get moved
into an own header file and CONFIG_SPINLOCK_DEBUG is turned on.
That results into this compile error:
In file included from include/linux/spinlock.h:378,
from include/linux/seqlock.h:29,
from include/linux/time.h:8,
from include/linux/timex.h:56,
from include/linux/sched.h:54,
from arch/m68k/kernel/asm-offsets.c:12:
include/linux/spinlock_api_smp.h: In function '__spin_unlock_irq':
include/linux/spinlock_api_smp.h:371: error: 'current' undeclared (first use in this function)
include/linux/spinlock_api_smp.h:371: error: (Each undeclared identifier is reported only once
include/linux/spinlock_api_smp.h:371: error: for each function it appears in.)
Including asm/current.h to asm-offsets.c wouldn't help since
the definition of struct task is needed. So we end up with ugly
header file include dependencies.
To solve this calculate the offset of the thread_info structure
into the task struct in asm-offsets.h and use the offset in
task_thread_info(). This works just like it does for IA64 as
well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Horst Hartmann <horsth@linux.vnet.ibm.com>
Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Miller <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <20090831124417.329662275@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/m68k/include')
| -rw-r--r-- | arch/m68k/include/asm/thread_info_mm.h | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/m68k/include/asm/thread_info_mm.h b/arch/m68k/include/asm/thread_info_mm.h index 6ea5c33b3c5..b6da3882be9 100644 --- a/arch/m68k/include/asm/thread_info_mm.h +++ b/arch/m68k/include/asm/thread_info_mm.h @@ -1,6 +1,10 @@ #ifndef _ASM_M68K_THREAD_INFO_H #define _ASM_M68K_THREAD_INFO_H +#ifndef ASM_OFFSETS_C +#include <asm/asm-offsets.h> +#endif +#include <asm/current.h> #include <asm/types.h> #include <asm/page.h> @@ -31,7 +35,12 @@ struct thread_info { #define init_thread_info (init_task.thread.info) #define init_stack (init_thread_union.stack) -#define task_thread_info(tsk) (&(tsk)->thread.info) +#ifdef ASM_OFFSETS_C +#define task_thread_info(tsk) ((struct thread_info *) NULL) +#else +#define task_thread_info(tsk) ((struct thread_info *)((char *)tsk+TASK_TINFO)) +#endif + #define task_stack_page(tsk) ((tsk)->stack) #define current_thread_info() task_thread_info(current) |