1. 05 Sep, 2018 1 commit
    • Chris Wilson's avatar
      drm/i915: Reduce context HW ID lifetime · 288f1ced
      Chris Wilson authored
      Future gen reduce the number of bits we will have available to
      differentiate between contexts, so reduce the lifetime of the ID
      assignment from that of the context to its current active cycle (i.e.
      only while it is pinned for use by the HW, will it have a constant ID).
      This means that instead of a max of 2k allocated contexts (worst case
      before fun with bit twiddling), we instead have a limit of 2k in flight
      contexts (minus a few that have been pinned by the kernel or by perf).
      
      To reduce the number of contexts id we require, we allocate a context id
      on first and mark it as pinned for as long as the GEM context itself is,
      that is we keep it pinned it while active on each engine. If we exhaust
      our context id space, then we try to reclaim an id from an idle context.
      In the extreme case where all context ids are pinned by active contexts,
      we force the system to idle in order to recover ids.
      
      We cannot reduce the scope of an HW-ID to an engine (allowing the same
      gem_context to have different ids on each engine) as in the future we
      will need to preassign an id before we know which engine the
      context is being executed on.
      
      v2: Improved commentary (Tvrtko) [I tried at least]
      
      References: https://bugs.freedesktop.org/show_bug.cgi?id=107788Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
      Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
      Cc: Mika Kuoppala <mika.kuoppala@intel.com>
      Cc: Michel Thierry <michel.thierry@intel.com>
      Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
      Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
      Reviewed-by: default avatarTvrtko Ursulin <tvrtko.ursulin@intel.com>
      Link: https://patchwork.freedesktop.org/patch/msgid/20180904153117.3907-1-chris@chris-wilson.co.uk
      288f1ced
  2. 04 Sep, 2018 6 commits
  3. 03 Sep, 2018 10 commits
  4. 01 Sep, 2018 2 commits
  5. 31 Aug, 2018 5 commits
  6. 30 Aug, 2018 4 commits
  7. 29 Aug, 2018 2 commits
  8. 28 Aug, 2018 9 commits
  9. 27 Aug, 2018 1 commit