plugins/cache: multicore cache modelling and minor tweaks

[Mahmoud Mandour <ma.mandourr@gmail.com>]

Hello,

This series introduce some minor improvements/bug fixes in the cache
plugins and multicore cache modelling.

Multi-core cache modelling is handled such that for full-system
emulation, a private L1 cache is maintained to each core available to
the system. For multi-threaded userspace emulation, a static number of
cores is maintained for the overall system, and every memory access go
through one of these, even if the number of fired threads is more than
that number.

Also, raising the levels of warnings induced some warnings, this is
fixed in it's own patch.

Patches that still need review (other patches are already queued):
    1. plugins/cache: Supported multicore cache modelling
    2. docs/devel/tcg-plugins: added cores arg to cache plugin

v1 -> v2:
    1. Dropped the patch with mitigating the use-after-free bug since
    it's not needed anymore (fixed by Alex Bennée here)
    2. Summed cache performance data as a post-processing step.
    3. Refactored appending core data to it's own function

Mahmoud Mandour (5):
  plugins/cache: Fixed a bug with destroying FIFO metadata
  plugins/cache: limited the scope of a mutex lock
  plugins/cache: Supported multicore cache modelling
  docs/devel/tcg-plugins: added cores arg to cache plugin
  plugins/cache: Fixed "function decl. is not a prototype" warnings

 contrib/plugins/cache.c    | 165 ++++++++++++++++++++++++++++---------
 docs/devel/tcg-plugins.rst |  13 +--
 2 files changed, 132 insertions(+), 46 deletions(-)

-- 
2.25.1