vcs.maemo.org Git - kernel-bfs/blob - kernel-bfs-2.6.28/debian/patches/sched-add-above-background-load-function.patch

   1 Add an "above background load" function which can be used for background
   2 tasks elsewhere (e.g. VM).
   3
   4 -ck
   5 ---
   6  include/linux/sched.h |    7 +++++++
   7  kernel/sched_bfs.c    |   20 ++++++++++++++++++++
   8  2 files changed, 27 insertions(+)
   9
  10 Index: linux-2.6.39-ck1/include/linux/sched.h
  11 ===================================================================
  12 --- linux-2.6.39-ck1.orig/include/linux/sched.h 2011-05-19 19:36:35.115273667 +1000
  13 +++ linux-2.6.39-ck1/include/linux/sched.h      2011-05-19 19:36:35.551273667 +1000
  14 @@ -1590,6 +1590,7 @@ static inline int iso_task(struct task_s
  15  {
  16         return (p->policy == SCHED_ISO);
  17  }
  18 +extern int above_background_load(void);
  19  #else /* CFS */
  20  extern int runqueue_is_locked(int cpu);
  21  extern void task_rq_unlock_wait(struct task_struct *p);
  22 @@ -1620,6 +1621,12 @@ static inline int iso_task(struct task_s
  23  {
  24         return 0;
  25  }
  26 +
  27 +/* Anyone feel like implementing this? */
  28 +static inline int above_background_load(void)
  29 +{
  30 +       return 1;
  31 +}
  32  #endif
  33
  34  /*
  35 Index: linux-2.6.39-ck1/kernel/sched_bfs.c
  36 ===================================================================
  37 --- linux-2.6.39-ck1.orig/kernel/sched_bfs.c    2011-05-19 19:36:35.121273667 +1000
  38 +++ linux-2.6.39-ck1/kernel/sched_bfs.c 2011-05-19 19:36:35.553273667 +1000
  39 @@ -563,6 +563,26 @@ static inline void __task_grq_unlock(voi
  40         grq_unlock();
  41  }
  42
  43 +/*
  44 + * Look for any tasks *anywhere* that are running nice 0 or better. We do
  45 + * this lockless for overhead reasons since the occasional wrong result
  46 + * is harmless.
  47 + */
  48 +int above_background_load(void)
  49 +{
  50 +       struct task_struct *cpu_curr;
  51 +       unsigned long cpu;
  52 +
  53 +       for_each_online_cpu(cpu) {
  54 +               cpu_curr = cpu_rq(cpu)->curr;
  55 +               if (unlikely(!cpu_curr))
  56 +                       continue;
  57 +               if (PRIO_TO_NICE(cpu_curr->static_prio) < 1)
  58 +                       return 1;
  59 +       }
  60 +       return 0;
  61 +}
  62 +
  63  #ifndef __ARCH_WANT_UNLOCKED_CTXSW
  64  static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
  65  {
  66