svn commit: r367573 - head/sys/vm

[Jonathan T. Looney]

Author: jtl
Date: Tue Nov 10 18:12:09 2020
New Revision: 367573
URL: https://svnweb.freebsd.org/changeset/base/367573

Log:
  When destroying a UMA zone which has a reserve (set with
  uma_zone_reserve()), messages like the following appear on the console:
  "Freed UMA keg (Test zone) was not empty (0 items). Lost 528 pages of
  memory."
  
  When keg_drain_domain() is draining the zone, it tries to keep the number
  of items specified in the reservation. However, when we are destroying the
  UMA zone, we do not need to keep those items. Therefore, when destroying a
  non-secondary and non-cache zone, we should reset the keg reservation to 0
  prior to draining the zone.
  
  Reviewed by:	markj
  Sponsored by:	Netflix
  Differential Revision:	https://reviews.freebsd.org/D27129

Modified:
  head/sys/vm/uma_core.c

Modified: head/sys/vm/uma_core.c
==============================================================================
--- head/sys/vm/uma_core.c	Tue Nov 10 18:10:50 2020	(r367572)
+++ head/sys/vm/uma_core.c	Tue Nov 10 18:12:09 2020	(r367573)
@@ -2791,6 +2791,10 @@ zone_dtor(void *arg, int size, void *udata)
 	rw_wlock(&uma_rwlock);
 	LIST_REMOVE(zone, uz_link);
 	rw_wunlock(&uma_rwlock);
+	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
+		keg = zone->uz_keg;
+		keg->uk_reserve = 0;
+	}
 	zone_reclaim(zone, M_WAITOK, true);
 
 	/*