lkml.org 
[lkml]   [2003]   [Dec]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[PATCH 2/5] 2.6.0 sched fork cleanup
    Move some fork related scheduler policy from fork.c to sched.c where it 
    belongs.


    Move some fork related scheduler policy from fork.c to sched.c where it belongs.


    linux-2.6-npiggin/include/linux/sched.h | 1
    linux-2.6-npiggin/kernel/fork.c | 30 ++-------------------------
    linux-2.6-npiggin/kernel/sched.c | 35 ++++++++++++++++++++++++++++++++
    3 files changed, 39 insertions(+), 27 deletions(-)

    diff -puN include/linux/sched.h~sched-fork-cleanup include/linux/sched.h
    --- linux-2.6/include/linux/sched.h~sched-fork-cleanup 2003-12-19 14:22:29.000000000 +1100
    +++ linux-2.6-npiggin/include/linux/sched.h 2003-12-19 14:22:29.000000000 +1100
    @@ -580,6 +580,7 @@ extern int FASTCALL(wake_up_process(stru
    static inline void kick_process(struct task_struct *tsk) { }
    #endif
    extern void FASTCALL(wake_up_forked_process(struct task_struct * tsk));
    +extern void FASTCALL(sched_fork(task_t * p));
    extern void FASTCALL(sched_exit(task_t * p));

    asmlinkage long sys_wait4(pid_t pid,unsigned int * stat_addr, int options, struct rusage * ru);
    diff -puN kernel/fork.c~sched-fork-cleanup kernel/fork.c
    --- linux-2.6/kernel/fork.c~sched-fork-cleanup 2003-12-19 14:22:29.000000000 +1100
    +++ linux-2.6-npiggin/kernel/fork.c 2003-12-19 14:22:29.000000000 +1100
    @@ -973,33 +973,9 @@ struct task_struct *copy_process(unsigne
    p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL);
    p->pdeath_signal = 0;

    - /*
    - * Share the timeslice between parent and child, thus the
    - * total amount of pending timeslices in the system doesn't change,
    - * resulting in more scheduling fairness.
    - */
    - local_irq_disable();
    - p->time_slice = (current->time_slice + 1) >> 1;
    - /*
    - * The remainder of the first timeslice might be recovered by
    - * the parent if the child exits early enough.
    - */
    - p->first_time_slice = 1;
    - current->time_slice >>= 1;
    - p->timestamp = sched_clock();
    - if (!current->time_slice) {
    - /*
    - * This case is rare, it happens when the parent has only
    - * a single jiffy left from its timeslice. Taking the
    - * runqueue lock is not a problem.
    - */
    - current->time_slice = 1;
    - preempt_disable();
    - scheduler_tick(0, 0);
    - local_irq_enable();
    - preempt_enable();
    - } else
    - local_irq_enable();
    + /* Perform scheduler related accounting */
    + sched_fork(p);
    +
    /*
    * Ok, add it to the run-queues and make it
    * visible to the rest of the system.
    diff -puN kernel/sched.c~sched-fork-cleanup kernel/sched.c
    --- linux-2.6/kernel/sched.c~sched-fork-cleanup 2003-12-19 14:22:29.000000000 +1100
    +++ linux-2.6-npiggin/kernel/sched.c 2003-12-19 14:22:29.000000000 +1100
    @@ -674,6 +674,41 @@ int wake_up_state(task_t *p, unsigned in
    }

    /*
    + * Perform scheduler related accounting for a newly forked process p.
    + * p is forked by current.
    + */
    +void sched_fork(task_t *p)
    +{
    + /*
    + * Share the timeslice between parent and child, thus the
    + * total amount of pending timeslices in the system doesn't change,
    + * resulting in more scheduling fairness.
    + */
    + local_irq_disable();
    + p->time_slice = (current->time_slice + 1) >> 1;
    + /*
    + * The remainder of the first timeslice might be recovered by
    + * the parent if the child exits early enough.
    + */
    + p->first_time_slice = 1;
    + current->time_slice >>= 1;
    + p->timestamp = sched_clock();
    + if (!current->time_slice) {
    + /*
    + * This case is rare, it happens when the parent has only
    + * a single jiffy left from its timeslice. Taking the
    + * runqueue lock is not a problem.
    + */
    + current->time_slice = 1;
    + preempt_disable();
    + scheduler_tick(0, 0);
    + local_irq_enable();
    + preempt_enable();
    + } else
    + local_irq_enable();
    +}
    +
    +/*
    * wake_up_forked_process - wake up a freshly forked process.
    *
    * This function will do some initial scheduler statistics housekeeping
    _
    \
     
     \ /
      Last update: 2005-03-22 13:59    [W:0.050 / U:0.136 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site