Fwd: [RFC] Kernel shared variables

[Giovanni Trematerra]

On Tue, Jun 5, 2012 at 12:12 AM, Konstantin Belousov
<kostikbel at gmail.com> wrote:
> On Mon, Jun 04, 2012 at 11:16:10PM +0200, Giovanni Trematerra wrote:
>> On Mon, Jun 4, 2012 at 8:19 PM, Konstantin Belousov <kostikbel at gmail.com> wrote:
>> > On Mon, Jun 04, 2012 at 11:01:57AM -0400, John Baldwin wrote:
>> >> On Sunday, June 03, 2012 6:49:27 am Bruce Evans wrote:
>> >> > On Sun, 3 Jun 2012, Konstantin Belousov wrote:
>>
>> >> I think duplicating this logic in userland would just be wasteful.  I have
>> >> a private fast gettimeofday() at my current job and it works by exporting
>> >> the current timehands structure (well, the equivalent) to userland.  The
>> >> userland bits then fetch a copy of the details and do the same as bintime().
>> >> (I move the math (bintime_addx() and the multiply)) out of the loop however.
>> > I started yesterday an implementation which uses shared page to export
>> > some variant of timehands, and uses auxv to provide the libc with a pointer
>> > to timehands when rdtsc is reasonable.
>> >
>> > I almost finished both 32bit and 64bit userspace, but there is
>> > kernel-side work left. Is your implementation ready or close to be ready
>> > for commit ? In other words, should I drop the efforts, or continue ?
>> >
>>
>> Hey wait, What are you doing?
>> This is completely unfair. You didn't even review my patch.
> I did. I am quite saddened if you did not note that I did reviewed your
> patch.
>
>> I really don't understand your way to completely ignore me and start implement
>> yesterday something you didn't care about for more than 3 years.
>> It costs me a lot of time and energy and I think I deserve more respect that
>> just be ignored.
>
> I did not ignored the problem for 3 years. In fact, I did some, IMO
> non-trivial development moving the whole issue forward. In particular, I
> developed the shared page infrastructure that are currently used (yes,
> we already do have properly implemented shared page and sub-allocator
> of memory from it). I did some relevant rtld and libc changes, in
> particular, libc now have full access and uses auxv. So I consider this
> statement as a form of insult.
>

Really? My apologize if you felt to be insulted. I didn't it on purpose.
Honestly I don't think there will be other occasions to hurt your
feelings.

>
> If you want to do full-flesged vdso at once, I will be very much pleasured
> and probably support this work technically.

Thank you for your offer. I'll appreciate it but I'm not going to work
on it anymore.

--
Gianni