redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

x86, percpu: Fix DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED()

Browse source 
DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED() put percpu variables in
.page_aligned section without adding any alignment restrictions.
Currently, this doesn't cause any problem because all users of the
macros have explicit page alignment and page-sized but it's much safer
to enforce page alignment from the macros.  After all, it's what they
claim to do.

Add __aligned(PAGE_SIZE) to DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED() and
drop explicit alignment from it users.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Tejun Heo 2009-08-03 14:10:11 +09:00
parent ed8d9adf35
commit 3e352aa8ee
2 changed files with 6 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
arch/x86/kernel/cpu/common.c
View file

@ -1008,8 +1008,7 @@ static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
};
static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ])
__aligned(PAGE_SIZE);
[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
/* May not be marked __init: used by software suspend */
void syscall_init(void)

8
include/linux/percpu-defs.h
View file

@ -69,11 +69,13 @@
/*
* Declaration/definition used for per-CPU variables that must be page aligned.
*/
#define DECLARE_PER_CPU_PAGE_ALIGNED(type, name) \
DECLARE_PER_CPU_SECTION(type, name, ".page_aligned")
#define DECLARE_PER_CPU_PAGE_ALIGNED(type, name) \
DECLARE_PER_CPU_SECTION(type, name, ".page_aligned") \
__aligned(PAGE_SIZE)
#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \
DEFINE_PER_CPU_SECTION(type, name, ".page_aligned")
DEFINE_PER_CPU_SECTION(type, name, ".page_aligned") \
__aligned(PAGE_SIZE)
/*
* Intermodule exports for per-CPU variables.