# HG changeset patch
# User Jan Beulich <jbeulich@xxxxxxxxxx>
# Date 1309549435 -3600
# Node ID 1b9cce28cab754b8cc0a7951e15a34768c90402e
# Parent 3261d198c3aa573ff7e8370b9787b72ba5dfa38a
x86: streamline page fault path
#PF is, in all "normal" usage models, the only potentially high
frequency (and hence performance sensitive) exception. Thus make it
the fall-through case into handle_exception (rather than
divide_error for x86-32 and not having one at all for x86-64).
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
---
diff -r 3261d198c3aa -r 1b9cce28cab7 xen/arch/x86/x86_32/entry.S
--- a/xen/arch/x86/x86_32/entry.S Fri Jul 01 20:43:02 2011 +0100
+++ b/xen/arch/x86/x86_32/entry.S Fri Jul 01 20:43:55 2011 +0100
@@ -426,9 +426,8 @@
jnz test_all_events
jmp restore_all_xen
-ENTRY(divide_error)
- pushl $TRAP_divide_error<<16
- ALIGN
+ENTRY(page_fault)
+ movw $TRAP_page_fault,2(%esp)
handle_exception:
FIXUP_RING0_GUEST_STACK
SAVE_ALL(1f,2f)
@@ -501,6 +500,10 @@
pushl $TRAP_no_device<<16
jmp handle_exception
+ENTRY(divide_error)
+ pushl $TRAP_divide_error<<16
+ jmp handle_exception
+
ENTRY(debug)
pushl $TRAP_debug<<16
jmp handle_exception
@@ -545,10 +548,6 @@
movw $TRAP_alignment_check,2(%esp)
jmp handle_exception
-ENTRY(page_fault)
- movw $TRAP_page_fault,2(%esp)
- jmp handle_exception
-
ENTRY(spurious_interrupt_bug)
pushl $TRAP_spurious_int<<16
jmp handle_exception
diff -r 3261d198c3aa -r 1b9cce28cab7 xen/arch/x86/x86_64/entry.S
--- a/xen/arch/x86/x86_64/entry.S Fri Jul 01 20:43:02 2011 +0100
+++ b/xen/arch/x86/x86_64/entry.S Fri Jul 01 20:43:55 2011 +0100
@@ -461,9 +461,11 @@
jz test_all_events
jmp compat_test_all_events
- ALIGN
+ENTRY(page_fault)
+ movl $TRAP_page_fault,4(%rsp)
/* No special register assumptions. */
-ENTRY(handle_exception)
+ .globl handle_exception
+handle_exception:
SAVE_ALL
handle_exception_saved:
testb $X86_EFLAGS_IF>>8,UREGS_eflags+1(%rsp)
@@ -585,10 +587,6 @@
movl $TRAP_alignment_check,4(%rsp)
jmp handle_exception
-ENTRY(page_fault)
- movl $TRAP_page_fault,4(%rsp)
- jmp handle_exception
-
ENTRY(spurious_interrupt_bug)
pushq $0
movl $TRAP_spurious_int,4(%rsp)
_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog
|
Home