d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

- Set the priority of the page zeroing thread using sched_prio() when the

Browse Source 
thread is created rather than adjusting the priority in the main
  function.  (kthread_create() should probably take the initial priority
  as an argument.)
- Only yield the CPU in the !PREEMPTION case if there are any other
  runnable threads.  Yielding when there isn't anything else better to do
  just wastes time in pointless context switches (albeit while the system
  is idle.)
This commit is contained in:
John Baldwin 2004-11-05 19:14:02 +00:00
parent 0811d60abc
commit 57ea1265bd
1 changed files with 5 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
sys/vm/vm_zeroidle.c
View File

@ -141,36 +141,26 @@ vm_page_zero_idle_wakeup(void)
static void
vm_pagezero(void __unused *arg)
{
struct rtprio rtp;
struct thread *td;
int pages, pri;
td = curthread;
rtp.prio = RTP_PRIO_MAX;
rtp.type = RTP_PRIO_IDLE;
pages = 0;
mtx_lock_spin(&sched_lock);
rtp_to_pri(&rtp, td->td_ksegrp);
pri = td->td_priority;
mtx_unlock_spin(&sched_lock);
idlezero_enable = idlezero_enable_default;
for (;;) {
if (vm_page_zero_check()) {
pages += vm_page_zero_idle();
vm_page_zero_idle();
#ifndef PREEMPTION
if (pages > idlezero_maxrun || sched_runnable()) {
if (sched_runnable()) {
mtx_lock_spin(&sched_lock);
mi_switch(SW_VOL, NULL);
mtx_unlock_spin(&sched_lock);
pages = 0;
}
#endif
} else {
vm_page_lock_queues();
wakeup_needed = TRUE;
msleep(&zero_state, &vm_page_queue_mtx, PDROP | pri,
"pgzero", hz * 300);
msleep(&zero_state, &vm_page_queue_mtx,
PDROP | td->td_priority, "pgzero", hz * 300);
pages = 0;
}
}
@ -194,6 +184,7 @@ pagezero_start(void __unused *arg)
pagezero_proc->p_flag |= P_NOLOAD;
PROC_UNLOCK(pagezero_proc);
mtx_lock_spin(&sched_lock);
sched_prio(FIRST_THREAD_IN_PROC(pagezero_proc), PRI_MAX_IDLE);
setrunqueue(FIRST_THREAD_IN_PROC(pagezero_proc), SRQ_BORING);
mtx_unlock_spin(&sched_lock);
}