- Don't call clear_resched() in userret(), instead, clear the resched flag

  in mi_switch() just before calling cpu_switch() so that the first switch
  after a resched request will satisfy the request.
- While I'm at it, move a few things into mi_switch() and out of
  cpu_switch(), specifically set the p_oncpu and p_lastcpu members of
  proc in mi_switch(), and handle the sched_lock state change across a
  context switch in mi_switch().
- Since cpu_switch() no longer handles the sched_lock state change, we
  have to setup an initial state for sched_lock in fork_exit() before we
  release it.

1 files changed, 8 insertions, 0 deletions

diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c
index 694bdf1..1f21422 100644
--- a/sys/kern/kern_synch.c
+++ b/sys/kern/kern_synch.c
@@ -848,6 +848,7 @@ mi_switch()
 	register struct rlimit *rlim;
 #endif
 	int x;
+	u_int sched_nest;
 
 	/*
 	 * XXX this spl is almost unnecessary.  It is partly to allow for
@@ -922,7 +923,14 @@ mi_switch()
 	PCPU_SET(switchtime, new_switchtime);
 	CTR4(KTR_PROC, "mi_switch: old proc %p (pid %d, %s), schedlock %p",
 		p, p->p_pid, p->p_comm, (void *) sched_lock.mtx_lock);
+	sched_nest = sched_lock.mtx_recurse;
+	curproc->p_lastcpu = curproc->p_oncpu;
+	curproc->p_oncpu = NOCPU;
+	clear_resched();
 	cpu_switch();
+	curproc->p_oncpu = PCPU_GET(cpuid);
+	sched_lock.mtx_recurse = sched_nest;
+	sched_lock.mtx_lock = curproc;
 	CTR4(KTR_PROC, "mi_switch: new proc %p (pid %d, %s), schedlock %p",
 		p, p->p_pid, p->p_comm, (void *) sched_lock.mtx_lock);
 	if (PCPU_GET(switchtime.tv_sec) == 0)