Re: Wait free LW_SHARED acquisition - v0.2

On 2014-10-08 13:13:33 -0400, Robert Haas wrote:
> On Wed, Oct 8, 2014 at 8:47 AM, Andres Freund <andres(at)2ndquadrant(dot)com> wrote:
> > I don't see that as being relevant. The difference is an instruction or
> > two - in the slow path we'll enter the kernel and sleep. This doesn't
> > matter in comparison.
> > And the code is *so* much more readable.
>
> I find the slist/dlist stuff actually quite difficult to get right
> compared to a hand-rolled linked list.

Really? I've spent more than a day debugging things with the current
code. And Heikki introduced a bug in it. If you look at how the code
looks before/after I find the difference pretty clear.

> But the really big problem is
> that the debugger can't do anything useful with it. You have to work
> out the structure-member offset in order to walk the list and manually
> cast to char *, adjust the pointer, and cast back. That sucks.

Hm. I can just do that with the debugger here. Not sure if that's
because I added the right thing to my .gdbinit or because I use the
correct compiler flags.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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