RE: [PATCH v4] Add git-grep threads param

From: Victor Leschuk <vleschuk@accesssoftek.com>
Date: Nov 9, 2015, 17:28 UTC
Message-ID: <6AE1604EE3EC5F4296C096518C6B77EE5D0FDABA18@mail.accesssoftek.com>
In-Reply-To: <20151109165343.GA29179@sigill.intra.peff.net>

 > if (list.nr || cached)

>        num_threads = 1;

 >  if (!num_threads)

>         num_threads = GREP_NUM_THREADS_DEFAULT;

>  and then later, instead of use_threads, do:

 >  if (num_threads <= 1) {
        ... do single-threaded version ...
  > } else {
        ... do multi-threaded version ...
  > }

 > That matches the logic in builtin/pack-objects.c.

Maybe use the simplest version (and keep num_numbers == 0 also as flag for all other checks in code like if(num_flags) .... ):

if (list.nr || cached )
  num_threads = 0; // do not use threads
else if (num_threads == 0)
  num_threads = online_cpus() <= 1 ? 0 : GREP_NUM_THREADS_DEFAULT;
else if (num_threads < 0)
  die(...)

// here we are num_threads > zero, so do nothing