1. 06 1月, 2016 1 次提交
  2. 23 11月, 2015 1 次提交
    • P
      treewide: Remove old email address · 90eec103
      Peter Zijlstra 提交于
      There were still a number of references to my old Red Hat email
      address in the kernel source. Remove these while keeping the
      Red Hat copyright notices intact.
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vince Weaver <vincent.weaver@maine.edu>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      90eec103
  3. 09 11月, 2015 1 次提交
  4. 20 10月, 2015 2 次提交
  5. 06 10月, 2015 2 次提交
  6. 18 9月, 2015 3 次提交
  7. 13 9月, 2015 20 次提交
  8. 12 8月, 2015 2 次提交
  9. 03 8月, 2015 8 次提交
    • Y
      sched/fair: Clean up load average references · 7ea241af
      Yuyang Du 提交于
      For cfs_rq, we have load.weight, runnable_load_avg, and load_avg.
      Clean up how they are used:
      
        - First, as group sched_entity already largely uses load_avg, we now expand
          to use load_avg in all cases.
      
        - Second, for CPU-wide load balancing, we choose to use runnable_load_avg
          in all cases, which is the same as before this series.
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: dietmar.eggemann@arm.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Cc: vincent.guittot@linaro.org
      Link: http://lkml.kernel.org/r/1436918682-4971-8-git-send-email-yuyang.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      7ea241af
    • Y
      sched/fair: Provide runnable_load_avg back to cfs_rq · 13962234
      Yuyang Du 提交于
      The cfs_rq's load_avg is composed of runnable_load_avg and blocked_load_avg.
      Before this series, sometimes the runnable_load_avg is used, and sometimes
      the load_avg is used. Completely replacing all uses of runnable_load_avg
      with load_avg may be too big a leap, i.e., the blocked_load_avg is concerned
      to result in overrated load. Therefore, we get runnable_load_avg back.
      
      The new cfs_rq's runnable_load_avg is improved to be updated with all of the
      runnable sched_eneities at the same time, so the one sched_entity updated and
      the others stale problem is solved.
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: dietmar.eggemann@arm.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Cc: vincent.guittot@linaro.org
      Link: http://lkml.kernel.org/r/1436918682-4971-7-git-send-email-yuyang.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      13962234
    • Y
      sched/fair: Remove task and group entity load when they are dead · 12695578
      Yuyang Du 提交于
      When task exits or group is destroyed, the entity's load should be
      removed from its parent cfs_rq's load. Otherwise, it will take time
      for the parent cfs_rq to decay the dead entity's load to 0, which
      is not desired.
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: dietmar.eggemann@arm.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Cc: vincent.guittot@linaro.org
      Link: http://lkml.kernel.org/r/1436918682-4971-6-git-send-email-yuyang.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      12695578
    • Y
      sched/fair: Init cfs_rq's sched_entity load average · 540247fb
      Yuyang Du 提交于
      The runnable load and utilization averages of cfs_rq's sched_entity
      were not initiated. Like done to a task, give new cfs_rq' sched_entity
      start values to heavy its load in infant time.
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: dietmar.eggemann@arm.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Cc: vincent.guittot@linaro.org
      Link: http://lkml.kernel.org/r/1436918682-4971-5-git-send-email-yuyang.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      540247fb
    • V
      sched/fair: Implement update_blocked_averages() for CONFIG_FAIR_GROUP_SCHED=n · 6c1d47c0
      Vincent Guittot 提交于
      The load and the utilization of idle CPUs must be updated periodically in
      order to decay the blocked part.
      
      If CONFIG_FAIR_GROUP_SCHED is not set, the load and util of idle cpus
      are not decayed and stay at the values set before becoming idle.
      Signed-off-by: NVincent Guittot <vincent.guittot@linaro.org>
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: dietmar.eggemann@arm.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Link: http://lkml.kernel.org/r/1436918682-4971-4-git-send-email-yuyang.du@intel.com
      [ Fixed up the SOB chain. ]
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      6c1d47c0
    • Y
      sched/fair: Rewrite runnable load and utilization average tracking · 9d89c257
      Yuyang Du 提交于
      The idea of runnable load average (let runnable time contribute to weight)
      was proposed by Paul Turner and Ben Segall, and it is still followed by
      this rewrite. This rewrite aims to solve the following issues:
      
      1. cfs_rq's load average (namely runnable_load_avg and blocked_load_avg) is
         updated at the granularity of an entity at a time, which results in the
         cfs_rq's load average is stale or partially updated: at any time, only
         one entity is up to date, all other entities are effectively lagging
         behind. This is undesirable.
      
         To illustrate, if we have n runnable entities in the cfs_rq, as time
         elapses, they certainly become outdated:
      
           t0: cfs_rq { e1_old, e2_old, ..., en_old }
      
         and when we update:
      
           t1: update e1, then we have cfs_rq { e1_new, e2_old, ..., en_old }
      
           t2: update e2, then we have cfs_rq { e1_old, e2_new, ..., en_old }
      
           ...
      
         We solve this by combining all runnable entities' load averages together
         in cfs_rq's avg, and update the cfs_rq's avg as a whole. This is based
         on the fact that if we regard the update as a function, then:
      
         w * update(e) = update(w * e) and
      
         update(e1) + update(e2) = update(e1 + e2), then
      
         w1 * update(e1) + w2 * update(e2) = update(w1 * e1 + w2 * e2)
      
         therefore, by this rewrite, we have an entirely updated cfs_rq at the
         time we update it:
      
           t1: update cfs_rq { e1_new, e2_new, ..., en_new }
      
           t2: update cfs_rq { e1_new, e2_new, ..., en_new }
      
           ...
      
      2. cfs_rq's load average is different between top rq->cfs_rq and other
         task_group's per CPU cfs_rqs in whether or not blocked_load_average
         contributes to the load.
      
         The basic idea behind runnable load average (the same for utilization)
         is that the blocked state is taken into account as opposed to only
         accounting for the currently runnable state. Therefore, the average
         should include both the runnable/running and blocked load averages.
         This rewrite does that.
      
         In addition, we also combine runnable/running and blocked averages
         of all entities into the cfs_rq's average, and update it together at
         once. This is based on the fact that:
      
           update(runnable) + update(blocked) = update(runnable + blocked)
      
         This significantly reduces the code as we don't need to separately
         maintain/update runnable/running load and blocked load.
      
      3. How task_group entities' share is calculated is complex and imprecise.
      
         We reduce the complexity in this rewrite to allow a very simple rule:
         the task_group's load_avg is aggregated from its per CPU cfs_rqs's
         load_avgs. Then group entity's weight is simply proportional to its
         own cfs_rq's load_avg / task_group's load_avg. To illustrate,
      
         if a task_group has { cfs_rq1, cfs_rq2, ..., cfs_rqn }, then,
      
         task_group_avg = cfs_rq1_avg + cfs_rq2_avg + ... + cfs_rqn_avg, then
      
         cfs_rqx's entity's share = cfs_rqx_avg / task_group_avg * task_group's share
      
      To sum up, this rewrite in principle is equivalent to the current one, but
      fixes the issues described above. Turns out, it significantly reduces the
      code complexity and hence increases clarity and efficiency. In addition,
      the new averages are more smooth/continuous (no spurious spikes and valleys)
      and updated more consistently and quickly to reflect the load dynamics.
      
      As a result, we have less load tracking overhead, better performance,
      and especially better power efficiency due to more balanced load.
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: dietmar.eggemann@arm.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Cc: vincent.guittot@linaro.org
      Link: http://lkml.kernel.org/r/1436918682-4971-3-git-send-email-yuyang.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      9d89c257
    • Y
      sched/fair: Remove rq's runnable avg · cd126afe
      Yuyang Du 提交于
      The current rq->avg is not used at all since its merge into the kernel,
      and the code is in the scheduler's hot path, so remove it.
      Tested-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
      Signed-off-by: NYuyang Du <yuyang.du@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Reviewed-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: arjan@linux.intel.com
      Cc: bsegall@google.com
      Cc: fengguang.wu@intel.com
      Cc: len.brown@intel.com
      Cc: morten.rasmussen@arm.com
      Cc: pjt@google.com
      Cc: rafael.j.wysocki@intel.com
      Cc: umgwanakikbuti@gmail.com
      Cc: vincent.guittot@linaro.org
      Link: http://lkml.kernel.org/r/1436918682-4971-2-git-send-email-yuyang.du@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      cd126afe
    • M
      sched/fair: Beef up wake_wide() · 63b0e9ed
      Mike Galbraith 提交于
      Josef Bacik reported that Facebook sees better performance with their
      1:N load (1 dispatch/node, N workers/node) when carrying an old patch
      to try very hard to wake to an idle CPU.  While looking at wake_wide(),
      I noticed that it doesn't pay attention to the wakeup of a many partner
      waker, returning 1 only when waking one of its many partners.
      
      Correct that, letting explicit domain flags override the heuristic.
      
      While at it, adjust task_struct bits, we don't need a 64-bit counter.
      Tested-by: NJosef Bacik <jbacik@fb.com>
      Signed-off-by: NMike Galbraith <umgwanakikbuti@gmail.com>
      [ Tidy things up. ]
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: kernel-team<Kernel-team@fb.com>
      Cc: morten.rasmussen@arm.com
      Cc: riel@redhat.com
      Link: http://lkml.kernel.org/r/1436888390.7983.49.camel@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      63b0e9ed