Re: Wait free LW_SHARED acquisition - v0.2

Robert Haas wrote:
> On Wed, Oct 8, 2014 at 8:47 AM, Andres Freund  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.  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.

As far as I recall you can get gdb to understand those pointer games
by defining some structs or macros.  Maybe we can improve by documenting
this.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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