diff options
| author | Tejun Heo <tj@kernel.org> | 2009-01-13 20:41:35 +0900 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-01-16 14:19:14 +0100 |
| commit | 3e5d8f978435bb9ba4dfe3f4514e65e7885db1a9 (patch) | |
| tree | 1ce55b2ec16a0bd59a29857e05215960d463a1d8 /arch/x86/kernel/setup_percpu.c | |
| parent | a698c823e15149941b0f0281527d0c0d1daf2639 (diff) | |
x86: make percpu symbols zerobased on SMP
[ Based on original patch from Christoph Lameter and Mike Travis. ]
This patch makes percpu symbols zerobased on x86_64 SMP by adding
PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on
the percpu output section and using it in vmlinux_64.lds.S. A new
PHDR is added as existing ones cannot contain sections near address
zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which
always points to the vaddr of the loaded percpu data.init region.
The following adjustments have been made to accomodate the address
change.
* code to locate percpu gdt_page in head_64.S is updated to add the
load address to the gdt_page offset.
* __per_cpu_load is used in places where access to the init data area
is necessary.
* pda->data_offset is initialized soon after C code is entered as zero
value doesn't work anymore.
This patch is mostly taken from Mike Travis' "x86_64: Base percpu
variables at zero" patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/setup_percpu.c')
| -rw-r--r-- | arch/x86/kernel/setup_percpu.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 56c63ac62b1..44845842e72 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -213,7 +213,7 @@ void __init setup_per_cpu_areas(void) } #endif per_cpu_offset(cpu) = ptr - __per_cpu_start; - memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start); + memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start); DBG("PERCPU: cpu %4d %p\n", cpu, ptr); } |