Re: [PATCH 2/6] m32r: Define THREAD_SIZE only once.

From: Hirokazu Takata
Date: Mon Sep 07 2009 - 01:53:21 EST


Hello,

From: Tim Abbott <tabbott@xxxxxxxxxxx>
Subject: [PATCH 2/6] m32r: Define THREAD_SIZE only once.
Date: Sun, 06 Sep 2009 23:12:55 -0400
> Previously, m32r's asm/thread_info.h defined THREAD_SIZE differently
> for assembly and C code; now that PAGE_SIZE is usable from assembly,
> these can be combined. Also, m32r's asm/processor.h redefines
> THREAD_SIZE to the same value; remove this redundant definition.
>
> Signed-off-by: Tim Abbott <tabbott@xxxxxxxxxxx>
> Cc: Hirokazu Takata <takata@xxxxxxxxxxxxxx>
> ---
> arch/m32r/include/asm/processor.h | 2 --
> arch/m32r/include/asm/thread_info.h | 6 ++----
> 2 files changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch/m32r/include/asm/processor.h b/arch/m32r/include/asm/processor.h
> index 1a997fc..8397c24 100644
> --- a/arch/m32r/include/asm/processor.h
> +++ b/arch/m32r/include/asm/processor.h
> @@ -140,8 +140,6 @@ unsigned long get_wchan(struct task_struct *p);
> #define KSTK_EIP(tsk) ((tsk)->thread.lr)
> #define KSTK_ESP(tsk) ((tsk)->thread.sp)
>
> -#define THREAD_SIZE (2*PAGE_SIZE)
> -
> #define cpu_relax() barrier()
>
> #endif /* _ASM_M32R_PROCESSOR_H */
> diff --git a/arch/m32r/include/asm/thread_info.h b/arch/m32r/include/asm/thread_info.h
> index 07bb5bd..787ac92 100644
> --- a/arch/m32r/include/asm/thread_info.h
> +++ b/arch/m32r/include/asm/thread_info.h
> @@ -55,6 +55,8 @@ struct thread_info {
>
> #define PREEMPT_ACTIVE 0x10000000
>
> +#define THREAD_SIZE (PAGE_SIZE << 1)
> +
> /*
> * macros/functions for gaining access to the thread information structure
> */
> @@ -76,8 +78,6 @@ struct thread_info {
> #define init_thread_info (init_thread_union.thread_info)
> #define init_stack (init_thread_union.stack)
>
> -#define THREAD_SIZE (2*PAGE_SIZE)
> -
> /* how to get the thread information struct from C */
> static inline struct thread_info *current_thread_info(void)
> {
> @@ -127,8 +127,6 @@ static inline unsigned int get_thread_fault_code(void)
>
> #else /* !__ASSEMBLY__ */
>
> -#define THREAD_SIZE 8192
> -
> /* how to get the thread information struct from ASM */
> #define GET_THREAD_INFO(reg) GET_THREAD_INFO reg
> .macro GET_THREAD_INFO reg
> --
> 1.6.3.3
>

This patch causes build errors:

$ m32r-linux-gnu-gcc -Wp,-MD,arch/m32r/kernel/.entry.o.d -nostdinc -isystem /usr/lib/gcc/m32r-linux-gnu/4.1.2/include -Iinclude -Iinclude2 -I/project/m32r-linux/kernel/dev/linux-2.6_dev.git/include -I/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/include -include include/linux/autoconf.h -D__KERNEL__ -D__ASSEMBLY__ -DNO_FPU -m32r2 -O2 -c -o arch/m32r/kernel/entry.o /project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S
/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S: Assembler messages:
/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S:124: Error: undefined symbol `PAGE_SIZE' in operation
/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S:150: Error: undefined symbol `PAGE_SIZE' in operation
/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S:159: Error: undefined symbol `PAGE_SIZE' in operation
/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S:189: Error: undefined symbol `PAGE_SIZE' in operation
/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/entry.S:268: Error: undefined symbol `PAGE_SIZE' in operation

It is because entry.s still has PAGE_SIZE symbol, after C preprocessing:

--- arch/m32r/kernel/entry.S ---
:
121 ENTRY(ret_from_fork)
122 pop r0
123 bl schedule_tail
124 GET_THREAD_INFO(r8)
125 bra syscall_exit
:
---

--- entry.s (preprocessed entry.S) ---
# 132 "/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/include/asm/th
read_info.h"
.macro GET_THREAD_INFO reg
ldi \reg, #-(PAGE_SIZE << 1)
and \reg, sp
.endm

:

# 121 "/project/m32r-linux/kernel/dev/linux-2.6_dev.git/arch/m32r/kernel/ent ry.S"
ENTRY_M ret_from_fork
pop r0
bl schedule_tail
GET_THREAD_INFO r8
bra syscall_exit
---


The PAGE_SIZE symbol is defined in asm/page.h, So I think asm/page.h
should be included at the top of asm/thread-info.h.
Here is a additional patch:

--- a/arch/m32r/include/asm/thread_info.h
+++ b/arch/m32r/include/asm/thread_info.h
@@ -10,6 +10,7 @@

#ifdef __KERNEL__

+#include <asm/page.h>
#ifndef __ASSEMBLY__
#include <asm/processor.h>
#endif

Signed-off-by: Hirokazu Takata <takata@xxxxxxxxxxxxxx>


Please update your patch if possible.

Thank you.

-- Takata
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/