[RFC] arm64:change jump_label to use branch instruction, not use NOP instr

[yalin.wang2010@gmail.com (yalin wang)]

> On Jul 31, 2015, at 15:52, Peter Zijlstra <peterz@infradead.org> wrote:
> 
> On Fri, Jul 31, 2015 at 03:41:37PM +0800, yalin wang wrote:
>> This change a little arch_static_branch(), use b . + 4 for false
>> return, why? According to aarch64 TRM, if both source and dest
>> instr are branch instr, can patch the instr directly, don't need
>> all cpu to do ISB for sync, this means we can call
>> aarch64_insn_patch_text_nosync() during patch_text(),
>> will improve the performance when change a static_key.
> 
> This doesn't parse.. What?
> 
> Also, this conflicts with the jump label patches I've got.


this is arch depend , you can see aarch64_insn_patch_text( ) for more info,
if aarch64_insn_hotpatch_safe() is true, will patch the text directly.

what is your git branch base? i make the patch based on linux-next branch,
maybe a little delay than yours , could you share your branch git address?
i can make a new based on yours .

Thanks