- Close races with signals and other AST's being triggered while we are in

  the process of exiting the kernel.  The ast() function now loops as long
  as the PS_ASTPENDING or PS_NEEDRESCHED flags are set.  It returns with
  preemption disabled so that any further AST's that arrive via an
  interrupt will be delayed until the low-level MD code returns to user
  mode.
- Use u_int's to store the tick counts for profiling purposes so that we
  do not need sched_lock just to read p_sticks.  This also closes a
  problem where the call to addupc_task() could screw up the arithmetic
  due to non-atomic reads of p_sticks.
- Axe need_proftick(), aston(), astoff(), astpending(), need_resched(),
  clear_resched(), and resched_wanted() in favor of direct bit operations
  on p_sflag.
- Fix up locking with sched_lock some.  In addupc_intr(), use sched_lock
  to ensure pr_addr and pr_ticks are updated atomically with setting
  PS_OWEUPC.  In ast() we clear pr_ticks atomically with clearing
  PS_OWEUPC.  We also do not grab the lock just to test a flag.
- Simplify the handling of Giant in ast() slightly.

Reviewed by:	bde (mostly)

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/sys/resourcevar.h b/sys/sys/resourcevar.h
index a610e2f..53ceac6 100644
--- a/sys/sys/resourcevar.h
+++ b/sys/sys/resourcevar.h
@@ -63,7 +63,7 @@ struct pstats {
 		u_long	pr_off;		/* pc offset */
 		u_long	pr_scale;	/* pc scaling */
 		u_long	pr_addr;	/* temp storage for addr until AST */
-		u_long	pr_ticks;	/* temp storage for ticks until AST */
+		u_int	pr_ticks;	/* temp storage for ticks until AST */
 	} p_prof;
 #define	pstat_endcopy	p_start
 	struct	timeval p_start;	/* starting time */