socsvn commit: r240175 - soc2012/rudot/sys/kern

[rudot at FreeBSD.org]

Author: rudot
Date: Tue Aug  7 15:35:17 2012
New Revision: 240175
URL: http://svnweb.FreeBSD.org/socsvn/?view=rev&rev=240175

Log:
  decay %cpu in racct containers (per-user, per-loginclass and per-jail) - work inb progress

Modified:
  soc2012/rudot/sys/kern/kern_racct.c

Modified: soc2012/rudot/sys/kern/kern_racct.c
==============================================================================
--- soc2012/rudot/sys/kern/kern_racct.c	Tue Aug  7 13:11:47 2012	(r240174)
+++ soc2012/rudot/sys/kern/kern_racct.c	Tue Aug  7 15:35:17 2012	(r240175)
@@ -157,7 +157,9 @@
 		RACCT_RECLAIMABLE | RACCT_DENIABLE | RACCT_SLOPPY,
 	[RACCT_WALLCLOCK] =
 		RACCT_IN_MILLIONS,
-	[RACCT_PCTCPU] = RACCT_RECLAIMABLE | RACCT_DENIABLE };
+	[RACCT_PCTCPU] = RACCT_DENIABLE };
+
+static const fixpt_t RACCT_DECAY_FACTOR = 0.9 * FSCALE;
 
 #ifdef SCHED_4BSD
 /*
@@ -579,7 +581,9 @@
 static int
 racct_set_check_locked(struct proc *p, int resource, uint64_t amount)
 {
-	int64_t diff, available;
+	int64_t available;
+	int64_t old_amount, decayed_amount;
+	int64_t diff, decayed_diff;
 
 	SDT_PROBE(racct, kernel, rusage, set, p, resource, amount, 0, 0);
 
@@ -591,21 +595,19 @@
 	/*
 	 * may be negative
 	 */
-	diff = amount - p->p_racct->r_resources[resource];
-#ifdef notyet
-	KASSERT(diff >= 0 || RACCT_IS_RECLAIMABLE(resource),
-	    ("racct_set: usage of non-reclaimable resource %d dropping",
-	     resource));
-#endif
+	old_amount = p->p_racct->r_resources[resource];
+	diff = amount - old_amount;
+	decayed_amount = old_amount * RACCT_DECAY_FACTOR / FSCALE;
+	decayed_diff = amount - decayed_amount;
 	available = INT64_MAX;
 #ifdef RCTL
 	available = rctl_pcpu_available(p);
 #endif
 	racct_alloc_resource(p->p_racct, resource, diff);
-	if (diff > 0)
-		racct_add_cred_locked(p->p_ucred, resource, diff);
-	else if (diff < 0)
-		racct_sub_cred_locked(p->p_ucred, resource, -diff);
+	if (decayed_diff > 0)
+		racct_add_cred_locked(p->p_ucred, resource, decayed_diff);
+	else if (decayed_diff < 0)
+		racct_sub_cred_locked(p->p_ucred, resource, -decayed_diff);
 
 	return (available <= diff);
 }
@@ -1017,6 +1019,38 @@
 }
 
 static void
+racct_decay_resource(struct racct *racct, void * res, void* dummy)
+{
+	int resource;
+	int64_t r_old, r_new;
+
+	mtx_assert(&racct_lock, MA_OWNED);
+
+	resource = *(int *) res;
+	r_old = racct->r_resources[resource];
+
+	/* If there is nothing to decay, just exit. */
+	if (r_old <= 0)
+		return;
+
+	r_new = r_old * RACCT_DECAY_FACTOR / FSCALE;
+	racct->r_resources[resource] = r_new;
+}
+
+static void
+racct_decay_pcpu(void)
+{
+	int resource;
+
+	mtx_assert(&racct_lock, MA_OWNED);
+
+	resource = RACCT_PCTCPU;
+	ui_racct_foreach(racct_decay_resource, &resource, NULL);
+	loginclass_racct_foreach(racct_decay_resource, &resource, NULL);
+	prison_racct_foreach(racct_decay_resource, &resource, NULL);
+}
+
+static void
 racctd(void)
 {
 	struct thread *td;
@@ -1027,6 +1061,10 @@
 	int over_limits;
 
 	for (;;) {
+		mtx_lock(&racct_lock);
+		racct_decay_pcpu();
+		mtx_unlock(&racct_lock);
+
 		sx_slock(&allproc_lock);
 
 		LIST_FOREACH(p, &zombproc, p_list) {