1. 17 May, 2012 2 commits
    • Peter Zijlstra's avatar
      sched: Remove stale power aware scheduling remnants and dysfunctional knobs · 8e7fbcbc
      Peter Zijlstra authored
      It's been broken forever (i.e. it's not scheduling in a power
      aware fashion), as reported by Suresh and others sending
      patches, and nobody cares enough to fix it properly ...
      so remove it to make space free for something better.
      
      There's various problems with the code as it stands today, first
      and foremost the user interface which is bound to topology
      levels and has multiple values per level. This results in a
      state explosion which the administrator or distro needs to
      master and almost nobody does.
      
      Furthermore large configuration state spaces aren't good, it
      means the thing doesn't just work right because it's either
      under so many impossibe to meet constraints, or even if
      there's an achievable state workloads have to be aware of
      it precisely and can never meet it for dynamic workloads.
      
      So pushing this kind of decision to user-space was a bad idea
      even with a single knob - it's exponentially worse with knobs
      on every node of the topology.
      
      There is a proposal to replace the user interface with a single
      3 state knob:
      
       sched_balance_policy := { performance, power, auto }
      
      where 'auto' would be the preferred default which looks at things
      like Battery/AC mode and possible cpufreq state or whatever the hw
      exposes to show us power use expectations - but there's been no
      progress on it in the past many months.
      
      Aside from that, the actual implementation of the various knobs
      is known to be broken. There have been sporadic attempts at
      fixing things but these always stop short of reaching a mergable
      state.
      
      Therefore this wholesale removal with the hopes of spurring
      people who care to come forward once again and work on a
      coherent replacement.
      Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Suresh Siddha <suresh.b.siddha@intel.com>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Cc: Vincent Guittot <vincent.guittot@linaro.org>
      Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twinsSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      8e7fbcbc
    • Ingo Molnar's avatar
      Merge branch 'sched/urgent' into sched/core · fac536f7
      Ingo Molnar authored
      Merge reason: bring together all the pending scheduler bits,
                    for the sched/numa changes.
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      fac536f7
  2. 14 May, 2012 7 commits
  3. 09 May, 2012 9 commits
  4. 07 May, 2012 4 commits
  5. 06 May, 2012 5 commits
  6. 05 May, 2012 10 commits
  7. 04 May, 2012 3 commits