On Fri, Feb 14, 2014 at 1:01 AM, Bert Huijben <b...@qqmail.nl> wrote:
> Sorry for the big number of small replies... > > > > And the 'cache->total_reads++;' calls? > > > > Doesn't that need a similar handling? > > > > Bert > > > > *From:* Bert Huijben [mailto:b...@qqmail.nl] > *Sent:* vrijdag 14 februari 2014 00:58 > *To:* 'Stefan Fuhrmann'; 'Ivan Zhakov' > > *Cc:* 'Subversion Development'; 'Stefan Fuhrman' > *Subject:* RE: svn commit: r1567996 - > /subversion/trunk/subversion/libsvn_subr/cache-membuffer.c > > > > [[ > > Well, you were wrong on your initial point ("missing zero crossing"). > > And you have been wrong on the "use the atomic functions" bit because > they don't cover 64 bit integers. The only available option is a critical > section (svn_mutex__t). > > ]] > > > > The 64 bit integer is for statistics only... > > > > If you just drop that one (that you only used for debugging your code... > There is no single read of that variable) the rest can be an atomic > increment. > entry->hit_count is 32 bits and atomic increment would be possible. cache->hit_count is 64 bits for which we don't have portable atomic operations. cache->total_xzy are 64 bits but are for dev statistics only and not an input for any logic. When they happen to be updated in a synchronized environment, that's fine, if not it's o.k., too. There is no need to write 3 or 4 extra serializable "increment" functions. -- Stefan^2.
