Re: [RFC PATCH 1/1] cleanup: use bool as return type for rwsem_is_locked

Pranith Kumar
2014-06-06T18:53:12Z

On Fri, Jun 6, 2014 at 2:41 PM, Davidlohr Bueso <davidlohr@hp.com> wrote:
> On Fri, 2014-06-06 at 19:56 +0200, Peter Zijlstra wrote:
>> On Fri, Jun 06, 2014 at 01:53:01PM -0400, Pranith Kumar wrote:
>> > On Fri, Jun 6, 2014 at 3:35 AM, Peter Zijlstra <peterz@infradead.org> wrote:
>> > >
>> > > Now in general, I don't particularly like such superfluous changes, so
>> > > unless you can show that GCC actually generates better code, I'd prefer
>> > > to keep things as they are.
>> >
>> > Fixed and checked the assembly. It saves us 2 bytes of code, not much. I am not sure if that is worth it :(
>>
>> still 2 bytes, so sure.
>>
>> Which gcc did you use and what arch did you build? That might be useful
>> info for the changelog.
>
> Yeah, please attach the output of 'size kernel/locking/rwsem.o' for both
> before and after. I think there's similar opportunity in other locking
> code as well.
>

Ok. Here is the data.

size kernel/locking/rwsem-spinlock.o

Before change to bool:

text data bss dec hex
1336 0 0 1336 538

After change to bool:

text data bss dec hex
1334 0 0 1334 536

--
Pranith