From: Nick Piggin <piggin@cyberone.com.au>
Move some fork related scheduler policy from fork.c to sched.c where it belongs.
include/linux/sched.h | 1 +
kernel/fork.c | 30 +++---------------------------
kernel/sched.c | 35 +++++++++++++++++++++++++++++++++++
3 files changed, 39 insertions(+), 27 deletions(-)
diff -puN include/linux/sched.h~np-sched-01-sched-fork-cleanup include/linux/sched.h
--- 25/include/linux/sched.h~np-sched-01-sched-fork-cleanup 2003-09-01 02:05:41.000000000 -0700
+++ 25-akpm/include/linux/sched.h 2003-09-01 02:05:41.000000000 -0700
@@ -561,6 +561,7 @@ extern int FASTCALL(wake_up_state(struct
extern int FASTCALL(wake_up_process(struct task_struct * tsk));
extern int FASTCALL(wake_up_process_kick(struct task_struct * tsk));
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~np-sched-01-sched-fork-cleanup kernel/fork.c
--- 25/kernel/fork.c~np-sched-01-sched-fork-cleanup 2003-09-01 02:05:41.000000000 -0700
+++ 25-akpm/kernel/fork.c 2003-09-01 02:05:41.000000000 -0700
@@ -912,33 +912,9 @@ 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->last_run = jiffies;
- 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~np-sched-01-sched-fork-cleanup kernel/sched.c
--- 25/kernel/sched.c~np-sched-01-sched-fork-cleanup 2003-09-01 02:05:41.000000000 -0700
+++ 25-akpm/kernel/sched.c 2003-09-01 02:05:41.000000000 -0700
@@ -533,6 +533,41 @@ 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->last_run = jiffies;
+ 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
_