On Fri, 6 Oct 2000 01:19:16 +0200,
Jamie Lokier <lk@tantalophile.demon.co.uk> wrote:
>David S. Miller wrote:
>> > These items are specifically placed into the data section, not the
>> > BSS, because these alignment games are not possible in the BSS.
>>
>> That would mean the BSS needs support alignment games.
>>
>> The problem is it doesn't work, please go try it.
>> So until it does work, I am going to revert this change.
>
>Put __attribute__ ((section (".data"))) into __tcp_clean_cacheline_pad
>and it should do what you want.
>
>Heck, section ".bss" might give you the alignment without the allocation
>but I'm not as confident about that.
Call me mad but you could actually try this instead of guessing.
# cat x.c
int __attribute__ ((section (".data"))) int1;
int __attribute__ ((section (".bss"))) int2;
int __attribute__ ((section (".data.init"))) int3;
int __attribute__ ((section (".data.init"))) int4 = 0;
# gcc -c -o x.o x.c
# nm x.o
00000000 t gcc2_compiled.
00000000 B int1
00000004 B int2
00000008 B int3
00000000 D int4
# objdump -h x.o
x.o: file format elf32-i386
Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00000000 00000000 00000000 00000034 2**2
CONTENTS, ALLOC, LOAD, READONLY, CODE
1 .data 00000000 00000000 00000000 00000034 2**2
CONTENTS, ALLOC, LOAD, DATA
2 .bss 0000000c 00000000 00000000 00000034 2**2
ALLOC
3 .note 00000014 00000000 00000000 00000034 2**0
CONTENTS, READONLY
4 .data.init 00000004 00000000 00000000 00000048 2**2
CONTENTS, ALLOC, LOAD, DATA
5 .comment 0000003d 00000000 00000000 0000004c 2**0
CONTENTS, READONLY
int[123] all end up in .bss, no matter what attributes you assign. If
you want special alignment then you must initialize the variable, even
if that means a zero initializer.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sat Oct 07 2000 - 21:00:18 EST