x86-64: Move kernelstack from PDA to per-cpu.
Also clean up PER_CPU_VAR usage in xen-asm_64.S
tj: * remove now unused stack_thread_info()
* s/kernelstack/kernel_stack/
* added FIXME comment in xen-asm_64.S
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 05794c5..5a23e89 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -17,6 +17,7 @@
#include <asm/processor-flags.h>
#include <asm/errno.h>
#include <asm/segment.h>
+#include <asm/percpu.h>
#include <xen/interface/xen.h>
@@ -28,12 +29,10 @@
#if 1
/*
- x86-64 does not yet support direct access to percpu variables
- via a segment override, so we just need to make sure this code
- never gets used
+ FIXME: x86_64 now can support direct access to percpu variables
+ via a segment override. Update xen accordingly.
*/
#define BUG ud2a
-#define PER_CPU_VAR(var, off) 0xdeadbeef
#endif
/*
@@ -45,14 +44,14 @@
BUG
/* Unmask events */
- movb $0, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
+ movb $0, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
/* Preempt here doesn't matter because that will deal with
any pending interrupts. The pending check may end up being
run on the wrong CPU, but that doesn't hurt. */
/* Test for pending */
- testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_pending)
+ testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
jz 1f
2: call check_events
@@ -69,7 +68,7 @@
ENTRY(xen_irq_disable_direct)
BUG
- movb $1, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
+ movb $1, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
ENDPATCH(xen_irq_disable_direct)
ret
ENDPROC(xen_irq_disable_direct)
@@ -87,7 +86,7 @@
ENTRY(xen_save_fl_direct)
BUG
- testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
+ testb $0xff, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
setz %ah
addb %ah,%ah
ENDPATCH(xen_save_fl_direct)
@@ -107,13 +106,13 @@
BUG
testb $X86_EFLAGS_IF>>8, %ah
- setz PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
+ setz PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_mask
/* Preempt here doesn't matter because that will deal with
any pending interrupts. The pending check may end up being
run on the wrong CPU, but that doesn't hurt. */
/* check for unmasked and pending */
- cmpw $0x0001, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_pending)
+ cmpw $0x0001, PER_CPU_VAR(xen_vcpu_info) + XEN_vcpu_info_pending
jz 1f
2: call check_events
1:
@@ -196,7 +195,7 @@
/* We're already on the usermode stack at this point, but still
with the kernel gs, so we can easily switch back */
movq %rsp, %gs:pda_oldrsp
- movq %gs:pda_kernelstack,%rsp
+ movq PER_CPU_VAR(kernel_stack),%rsp
pushq $__USER_DS
pushq %gs:pda_oldrsp
@@ -213,7 +212,7 @@
/* We're already on the usermode stack at this point, but still
with the kernel gs, so we can easily switch back */
movq %rsp, %gs:pda_oldrsp
- movq %gs:pda_kernelstack, %rsp
+ movq PER_CPU_VAR(kernel_stack), %rsp
pushq $__USER32_DS
pushq %gs:pda_oldrsp