- Move p_cpulimit to struct proc from struct plimit and protect it with

  sched_lock.  This means that we no longer access p_limit in mi_switch()
  and the p_limit pointer can be protected by the proc lock.
- Remove PRS_ZOMBIE check from CPU limit test in mi_switch().  PRS_ZOMBIE
  processes don't call mi_switch(), and even if they did there is no longer
  the danger of p_limit being NULL (which is what the original zombie check
  was added for).
- When we bump the current processes soft CPU limit in ast(), just bump the
  private p_cpulimit instead of the shared rlimit.  This fixes an XXX for
  some value of fix.  There is still a (probably benign) bug in that this
  code doesn't check that the new soft limit exceeds the hard limit.

Inspired by:	bde (2)

1 files changed, 4 insertions, 3 deletions

diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index 9eaeec2..c53edc3 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -241,9 +241,10 @@ ast(struct trapframe *framep)
 			killproc(p, "exceeded maximum CPU limit");
 		else {
 			psignal(p, SIGXCPU);
-			if (rlim->rlim_cur < rlim->rlim_max)
-				/* XXX: we should make a private copy. */
-				rlim->rlim_cur += 5;
+			mtx_lock_spin(&sched_lock);
+			if (p->p_cpulimit < rlim->rlim_max)
+				p->p_cpulimit += 5;
+			mtx_unlock_spin(&sched_lock);
 		}
 		PROC_UNLOCK(p);
 	}