kernel_optimize_test/arch/tile/kernel/vmlinux.lds.S
Tejun Heo 0415b00d17 percpu: Always align percpu output section to PAGE_SIZE
Percpu allocator honors alignment request upto PAGE_SIZE and both the
percpu addresses in the percpu address space and the translated kernel
addresses should be aligned accordingly.  The calculation of the
former depends on the alignment of percpu output section in the kernel
image.

The linker script macros PERCPU_VADDR() and PERCPU() are used to
define this output section and the latter takes @align parameter.
Several architectures are using @align smaller than PAGE_SIZE breaking
percpu memory alignment.

This patch removes @align parameter from PERCPU(), renames it to
PERCPU_SECTION() and makes it always align to PAGE_SIZE.  While at it,
add PCPU_SETUP_BUG_ON() checks such that alignment problems are
reliably detected and remove percpu alignment comment recently added
in workqueue.c as the condition would trigger BUG way before reaching
there.

For um, this patch raises the alignment of percpu area.  As the area
is in .init, there shouldn't be any noticeable difference.

This problem was discovered by David Howells while debugging boot
failure on mn10300.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: user-mode-linux-devel@lists.sourceforge.net
2011-03-24 18:50:09 +01:00

96 lines
2.0 KiB
ArmAsm

#include <asm-generic/vmlinux.lds.h>
#include <asm/page.h>
#include <asm/cache.h>
#include <asm/thread_info.h>
#include <hv/hypervisor.h>
/* Text loads starting from the supervisor interrupt vector address. */
#define TEXT_OFFSET MEM_SV_INTRPT
OUTPUT_ARCH(tile)
ENTRY(_start)
jiffies = jiffies_64;
PHDRS
{
intrpt1 PT_LOAD ;
text PT_LOAD ;
data PT_LOAD ;
}
SECTIONS
{
/* Text is loaded with a different VA than data; start with text. */
#undef LOAD_OFFSET
#define LOAD_OFFSET TEXT_OFFSET
/* Interrupt vectors */
.intrpt1 (LOAD_OFFSET) : AT ( 0 ) /* put at the start of physical memory */
{
_text = .;
_stext = .;
*(.intrpt1)
} :intrpt1 =0
/* Hypervisor call vectors */
#include "hvglue.lds"
/* Now the real code */
. = ALIGN(0x20000);
.text : AT (ADDR(.text) - LOAD_OFFSET) {
HEAD_TEXT
SCHED_TEXT
LOCK_TEXT
__fix_text_end = .; /* tile-cpack won't rearrange before this */
TEXT_TEXT
*(.text.*)
*(.coldtext*)
*(.fixup)
*(.gnu.warning)
} :text =0
_etext = .;
/* "Init" is divided into two areas with very different virtual addresses. */
INIT_TEXT_SECTION(PAGE_SIZE)
/* Now we skip back to PAGE_OFFSET for the data. */
. = (. - TEXT_OFFSET + PAGE_OFFSET);
#undef LOAD_OFFSET
#define LOAD_OFFSET PAGE_OFFSET
. = ALIGN(PAGE_SIZE);
VMLINUX_SYMBOL(_sinitdata) = .;
INIT_DATA_SECTION(16) :data =0
PERCPU_SECTION(L2_CACHE_BYTES)
. = ALIGN(PAGE_SIZE);
VMLINUX_SYMBOL(_einitdata) = .;
_sdata = .; /* Start of data section */
RO_DATA_SECTION(PAGE_SIZE)
/* initially writeable, then read-only */
. = ALIGN(PAGE_SIZE);
__w1data_begin = .;
.w1data : AT(ADDR(.w1data) - LOAD_OFFSET) {
VMLINUX_SYMBOL(__w1data_begin) = .;
*(.w1data)
VMLINUX_SYMBOL(__w1data_end) = .;
}
RW_DATA_SECTION(L2_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
_edata = .;
EXCEPTION_TABLE(L2_CACHE_BYTES)
NOTES
BSS_SECTION(8, PAGE_SIZE, 1)
_end = . ;
STABS_DEBUG
DWARF_DEBUG
DISCARDS
}