Module Name: src
Committed By: pooka
Date: Fri Jan 28 17:04:39 UTC 2011
Modified Files:
src/sys/rump/librump/rumpkern: locks.c
Log Message:
If we are "unsleepable" due to a dying proc, yield() instead of
returning directly. This allows other threads to run possible
setting a condition we are waiting on.
Fixes a busyloop condition which could be entered from vfs_unmountall()
where we were waiting for vrele_pending and the vrele thread could
not run since we were hogging the CPU.
To generate a diff of this commit:
cvs rdiff -u -r1.49 -r1.50 src/sys/rump/librump/rumpkern/locks.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/rump/librump/rumpkern/locks.c
diff -u src/sys/rump/librump/rumpkern/locks.c:1.49 src/sys/rump/librump/rumpkern/locks.c:1.50
--- src/sys/rump/librump/rumpkern/locks.c:1.49 Fri Jan 28 16:58:28 2011
+++ src/sys/rump/librump/rumpkern/locks.c Fri Jan 28 17:04:39 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: locks.c,v 1.49 2011/01/28 16:58:28 pooka Exp $ */
+/* $NetBSD: locks.c,v 1.50 2011/01/28 17:04:39 pooka Exp $ */
/*
* Copyright (c) 2007, 2008 Antti Kantee. All Rights Reserved.
@@ -29,7 +29,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: locks.c,v 1.49 2011/01/28 16:58:28 pooka Exp $");
+__KERNEL_RCSID(0, "$NetBSD: locks.c,v 1.50 2011/01/28 17:04:39 pooka Exp $");
#include <sys/param.h>
#include <sys/kmem.h>
@@ -285,10 +285,11 @@
if (__predict_false(l->l_flag & LW_RUMP_DYING)) {
/*
- * sleepq code expects us to sleep, so set l_mutex
- * back to cpu lock here if we didn't.
+ * yield() here, someone might want the cpu
+ * to set a condition. otherwise we'll just
+ * loop forever.
*/
- l->l_mutex = l->l_cpu->ci_schedstate.spc_mutex;
+ yield();
return EINTR;
}
