svn commit: r281487 - stable/10/sys/kern

[Alexander Motin]

Author: mav
Date: Mon Apr 13 09:17:57 2015
New Revision: 281487
URL: https://svnweb.freebsd.org/changeset/base/281487

Log:
  MFC r280850:
  Periodically wake up threads waiting for vmem(9) resources, so they could
  ask for resource reclamation again.
  
  This is kind of dirty hack, but as last resort this is better then stuck
  indefinitely because of KVA fragmentation, waiting until some random event
  free something sufficient.  OpenSolaris also has this hack in its vmem(9).

Modified:
  stable/10/sys/kern/subr_vmem.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/kern/subr_vmem.c
==============================================================================
--- stable/10/sys/kern/subr_vmem.c	Mon Apr 13 08:35:03 2015	(r281486)
+++ stable/10/sys/kern/subr_vmem.c	Mon Apr 13 09:17:57 2015	(r281487)
@@ -746,6 +746,12 @@ vmem_periodic(void *unused, int pending)
 		/* Grow in powers of two.  Shrink less aggressively. */
 		if (desired >= current * 2 || desired * 4 <= current)
 			vmem_rehash(vm, desired);
+
+		/*
+		 * Periodically wake up threads waiting for resources,
+		 * so they could ask for reclamation again.
+		 */
+		VMEM_CONDVAR_BROADCAST(vm);
 	}
 	mtx_unlock(&vmem_list_lock);