On Tue, Jun 19, 2018 at 12:48:54PM -0700, Nadav Amit wrote:
> diff --git a/arch/x86/include/asm/jump_label.h
> b/arch/x86/include/asm/jump_label.h
> index 8c0de4282659..f321a50e6727 100644
> --- a/arch/x86/include/asm/jump_label.h
> +++ b/arch/x86/include/asm/jump_label.h
> @@ -108,6 +99,26 @@ struct jump_entry {
> .popsection
> .endm
>
> +.macro STATIC_BRANCH_NOP l_yes:req key:req branch:req
> +1:
> + .byte STATIC_KEY_INIT_NOP
> + .pushsection __jump_table, "aw"
> + _ASM_ALIGN
> + _ASM_PTR 1b, \l_yes, \key + \branch
> + .popsection
> +.endm
> +
> +.macro STATIC_BRANCH_JMP l_yes:req key:req branch:req
> +1:
> + .byte 0xe9
> + .long \l_yes - 2f
> +2:
> + .pushsection __jump_table, "aw"
> + _ASM_ALIGN
> + _ASM_PTR 1b, \l_yes, \key + \branch
> + .popsection
> +.endm
> +
> #endif /* __ASSEMBLY__ */
>
> #endif
This also allows the below, the old macros were slightly easier to
understand, but not in wide use, in fact, only a single user, so I see
no point in preserving them.
---
--- a/arch/x86/include/asm/jump_label.h
+++ b/arch/x86/include/asm/jump_label.h
@@ -67,38 +67,6 @@ struct jump_entry {
#else /* __ASSEMBLY__ */
-.macro STATIC_JUMP_IF_TRUE target, key, def
-.Lstatic_jump_\@:
- .if \def
- /* Equivalent to "jmp.d32 \target" */
- .byte 0xe9
- .long \target - .Lstatic_jump_after_\@
-.Lstatic_jump_after_\@:
- .else
- .byte STATIC_KEY_INIT_NOP
- .endif
- .pushsection __jump_table, "aw"
- _ASM_ALIGN
- _ASM_PTR .Lstatic_jump_\@, \target, \key
- .popsection
-.endm
-
-.macro STATIC_JUMP_IF_FALSE target, key, def
-.Lstatic_jump_\@:
- .if \def
- .byte STATIC_KEY_INIT_NOP
- .else
- /* Equivalent to "jmp.d32 \target" */
- .byte 0xe9
- .long \target - .Lstatic_jump_after_\@
-.Lstatic_jump_after_\@:
- .endif
- .pushsection __jump_table, "aw"
- _ASM_ALIGN
- _ASM_PTR .Lstatic_jump_\@, \target, \key + 1
- .popsection
-.endm
-
.macro STATIC_BRANCH_NOP l_yes:req key:req branch:req
1:
.byte STATIC_KEY_INIT_NOP
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index 352e70cd33e8..7c0d2ace8839 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -338,7 +338,7 @@ For 32-bit we have the following conventions - kernel is
built with
.macro CALL_enter_from_user_mode
#ifdef CONFIG_CONTEXT_TRACKING
#ifdef HAVE_JUMP_LABEL
- STATIC_JUMP_IF_FALSE .Lafter_call_\@, context_tracking_enabled, def=0
+ STATIC_BRANCH_JMP .Lafter_call_\@, context_tracking_enabled, 1
#endif
call enter_from_user_mode
.Lafter_call_\@:
