From fb84bd1bd8ca06bb8bf846d8672ab2f216831c4c Mon Sep 17 00:00:00 2001
From: avg <avg@ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f>
Date: Sat, 4 Mar 2017 12:05:50 +0000
Subject: [PATCH] MFC r314272: call vm_lowmem hook in uma_reclaim_worker

git-svn-id: svn://svn.freebsd.org/base/stable/10@314664 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
---
 sys/vm/uma_core.c   | 4 ++++
 sys/vm/vm_kern.c    | 8 +++++---
 sys/vm/vm_pageout.c | 2 +-
 sys/vm/vm_pageout.h | 6 ++++++
 4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c
index 11dceebb7..908db9ece 100644
--- a/sys/vm/uma_core.c
+++ b/sys/vm/uma_core.c
@@ -64,6 +64,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bitset.h>
+#include <sys/eventhandler.h>
 #include <sys/kernel.h>
 #include <sys/types.h>
 #include <sys/queue.h>
@@ -3244,6 +3245,9 @@ uma_reclaim_worker(void *arg __unused)
 		    "umarcl", 0);
 		if (uma_reclaim_needed) {
 			uma_reclaim_needed = 0;
+			sx_xunlock(&uma_drain_lock);
+			EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
+			sx_xlock(&uma_drain_lock);
 			uma_reclaim_locked(true);
 		}
 	}
diff --git a/sys/vm/vm_kern.c b/sys/vm/vm_kern.c
index d605c236e..df5a26b52 100644
--- a/sys/vm/vm_kern.c
+++ b/sys/vm/vm_kern.c
@@ -542,11 +542,13 @@ debug_vm_lowmem(SYSCTL_HANDLER_ARGS)
 	error = sysctl_handle_int(oidp, &i, 0, req);
 	if (error)
 		return (error);
-	if (i)	 
-		EVENTHANDLER_INVOKE(vm_lowmem, 0);
+	if ((i & ~(VM_LOW_KMEM | VM_LOW_PAGES)) != 0)
+		return (EINVAL);
+	if (i != 0)
+		EVENTHANDLER_INVOKE(vm_lowmem, i);
 	return (0);
 }
 
 SYSCTL_PROC(_debug, OID_AUTO, vm_lowmem, CTLTYPE_INT | CTLFLAG_RW, 0, 0,
-    debug_vm_lowmem, "I", "set to trigger vm_lowmem event");
+    debug_vm_lowmem, "I", "set to trigger vm_lowmem event with given flags");
 #endif
diff --git a/sys/vm/vm_pageout.c b/sys/vm/vm_pageout.c
index 6928c2000..41297e3f3 100644
--- a/sys/vm/vm_pageout.c
+++ b/sys/vm/vm_pageout.c
@@ -962,7 +962,7 @@ vm_pageout_scan(struct vm_domain *vmd, int pass)
 		 * Decrease registered cache sizes.
 		 */
 		SDT_PROBE0(vm, , , vm__lowmem_scan);
-		EVENTHANDLER_INVOKE(vm_lowmem, 0);
+		EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_PAGES);
 		/*
 		 * We do this explicitly after the caches have been
 		 * drained above.
diff --git a/sys/vm/vm_pageout.h b/sys/vm/vm_pageout.h
index c7b4e9003..93f911ced 100644
--- a/sys/vm/vm_pageout.h
+++ b/sys/vm/vm_pageout.h
@@ -86,6 +86,12 @@ extern int vm_pageout_page_count;
 #define	VM_OOM_MEM	1
 #define	VM_OOM_SWAPZ	2
 
+/*
+ * vm_lowmem flags.
+ */
+#define	VM_LOW_KMEM	0x01
+#define	VM_LOW_PAGES	0x02
+
 /*
  *	Exported routines.
  */
-- 
2.45.0