Re: [PATCH -v2 6/8] jump_label: Add a new static_key interface

[Andy Lutomirski]

On Mon, Aug 3, 2015 at 8:37 PM, Borislav Petkov <bp@xxxxxxxxx> wrote:
> On Mon, Aug 03, 2015 at 05:57:57PM -0400, Steven Rostedt wrote:
>> That's implementation details, not a general concept that users will
>> need to know about.
>
> Why?
>
> It is a branch, regardless of which insn is used on which arch - it is
> either active and you *branch* to that code or *inactive* and you don't.
> So now it is actually what it should've been from the beginning...

Except that, with the new interface, static_key_likely is the other
way around, right?  If the key is true (i.e. enabled), then it doesn't
branch.

I think of the key as a boolean thing that happens to work by code
patching under the hood.  The fancy patching affects the performance
but doesn't really make it functionally different from a regular
variable.  How about making it extra explicit:

static_key_set(&key, value);

where value is a bool or maybe even an unsigned int?

--Andy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/