PERFORCE change 105247 for review

[Chris Jones]

http://perforce.freebsd.org/chv.cgi?CH=105247

Change 105247 by cdjones at cdjones_meanook on 2006/08/29 05:52:13

	Quick speedup per 21 Aug 2006 mail to freebsd-hackers@; if we have no jails, there's no reason to do any of this.

Affected files ...

.. //depot/projects/soc2006/cdjones_jail/src/sys/kern/sched_4bsd.c#10 edit

Differences ...

==== //depot/projects/soc2006/cdjones_jail/src/sys/kern/sched_4bsd.c#10 (text+ko) ====

@@ -463,13 +463,13 @@
 	 * TODO: this is excessively icky.
 	 */
 	sx_slock(&allproc_lock);
-	mtx_lock(&allprison_mtx);
-	if (prisoncount) {
+	if (prisoncount && sched_limitjailcpu) {
+		mtx_lock(&allprison_mtx);
 		LIST_FOREACH(pr, &allprison, pr_list) {
 			pr->pr_estcpu = 0;
 		}
+		total_est_cpu = 0;
 	}
-	total_est_cpu = 0;
 	FOREACH_PROC_IN_SYSTEM(p) {
 		/*
 		 * Prevent state changes and protect run queue.
@@ -554,12 +554,13 @@
 			if (kg->kg_slptime > 1)
 				continue;
 			kg->kg_estcpu = decay_cpu(loadfac, kg->kg_estcpu);
-			total_est_cpu += kg->kg_estcpu;
-			if (sched_limitjailcpu && 
-			    NULL != kg->kg_proc->p_ucred &&
-			    NULL != kg->kg_proc->p_ucred->cr_prison)
-				kg->kg_proc->p_ucred->cr_prison->pr_estcpu += 
-					kg->kg_estcpu;
+			if (prisoncount && sched_limitjailcpu) {
+				total_est_cpu += kg->kg_estcpu;
+				if (NULL != kg->kg_proc->p_ucred &&
+				    NULL != kg->kg_proc->p_ucred->cr_prison)
+					kg->kg_proc->p_ucred->cr_prison->pr_estcpu += 
+						kg->kg_estcpu;
+			}
 		      	resetpriority(kg);
 			FOREACH_THREAD_IN_GROUP(kg, td) {
 				resetpriority_thread(td, kg);
@@ -567,7 +568,8 @@
 		} /* end of ksegrp loop */
 		mtx_unlock_spin(&sched_lock);
 	} /* end of process loop */
-	mtx_unlock(&allprison_mtx);
+	if (prisoncount && sched_limitjailcpu)
+		mtx_unlock(&allprison_mtx);
 	sx_sunlock(&allproc_lock);
 }
 
@@ -582,7 +584,7 @@
 	u_int32_t shares = 0;
 
 	for (;;) {
-		if (sched_limitjailcpu) {
+		if (prisoncount && sched_limitjailcpu) {
 			/* 
 			 * Update total jail CPU shares in case they've changed.
 			 * Safe to read pr_sched_shares without mutex because
@@ -645,7 +647,7 @@
 	if (kg->kg_pri_class == PRI_TIMESHARE) {
 		newpriority = PUSER + kg->kg_estcpu / INVERSE_ESTCPU_WEIGHT +
 			NICE_WEIGHT * (kg->kg_proc->p_nice - PRIO_MIN);
-		if (sched_limitjailcpu && NULL != pr) {
+		if (prisoncount && sched_limitjailcpu && NULL != pr) {
 			/* 
 			 * Skew the priority by the jail's share of CPU resources.
 			 * The unjailed processes get half the CPU time.