On 07/31/2009 02:23 PM, Richard Henderson wrote:
Similarly it is *not* a bug that the page_aligned sections were before
data, because we already knew we had 2 page alignment from the end of
init + 2 pages of init_thread.
Indeed, I'll go further and say that the common definition of
RW_DATA_SECTION is buggy.
#define RW_DATA_SECTION(cacheline, nosave, pagealigned, inittask) \
. = ALIGN(PAGE_SIZE); \
.data : AT(ADDR(.data) - LOAD_OFFSET) { \
INIT_TASK(inittask) \
CACHELINE_ALIGNED_DATA(cacheline) \
READ_MOSTLY_DATA(cacheline) \
DATA_DATA \
CONSTRUCTORS \
NOSAVE_DATA(nosave) \
PAGE_ALIGNED_DATA(pagealigned) \
}
Given that we align the entire .data section why have interior padding
to re-align for page-aligned data? Surely a better ordering would be
. = ALIGN(PAGE_SIZE);
.data : AT(ADDR(.data) - LOAD_OFFSET) {
INIT_TASK(inittask)
NOSAVE_DATA
PAGE_ALIGNED_DATA(pagealigned)
CACHELINE_ALIGNED_DATA(cacheline)
READ_MOSTLY_DATA(cacheline)
DATA_DATA
CONSTRUCTORS
}
with that change, and without
- . = ALIGN(2 * PAGE_SIZE);
+ . = ALIGN(PAGE_SIZE);
__init_end = .;
the patch looks like it'd be ok. All you're doing with this fragment is
failing to free a page of padding. You could change it to
. = ALIGN(THREAD_SIZE)
if it makes you feel better.
r~
--
To unsubscribe from this list: send the line "unsubscribe linux-alpha" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
