15 Dec
2009
15 Dec
'09
3:42 p.m.
On 12/15/2009 08:04 PM, Paul Davis wrote:
On Tue, Dec 15, 2009 at 1:47 PM, Tim Blechmann
<tim(a)klingt.org> wrote:
the jack ringbuffer code is not multiprocessor
safe then ... it is prbly
not an issue for jack1, but maybe for jack2, if it is used there ...
this was discussed at some considerable length on jack-devel last year, IIRC.
for single reader/single writer ringbuffers, i believe that we
concluded that memory barriers are not necessary.
No, to me the conclusion was: we can't programmatically prove that memory
barriers are needed (even on the most vulnerable architectures), but the theory
say that they are, and they should be added for correctness.
--
Olivier
>
http://github.com/radarsat1/dimple/blob/master/src/CircBuffer.h
you should add memory barriers, when reading or writing to the reader or
Actually,
his implementation is similar to ringbuffer.c in
libjack... and assumes that reading and writing can happen
atomically (as was pointed out by someone else) -- which can
be managed with single reader / single writer
requirement.[a]
Unless I've misunderstood the code, ringbuffer.c is /not/
using special atomic operations.