Module Name: src
Committed By: ad
Date: Mon Jan 27 21:05:43 UTC 2020
Modified Files:
src/sys/kern: kern_lock.c
src/sys/sys: lock.h
Log Message:
Add a kernel_lock_plug_leak() that drops any holds and tries to identify
the baddy.
To generate a diff of this commit:
cvs rdiff -u -r1.167 -r1.168 src/sys/kern/kern_lock.c
cvs rdiff -u -r1.87 -r1.88 src/sys/sys/lock.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_lock.c
diff -u src/sys/kern/kern_lock.c:1.167 src/sys/kern/kern_lock.c:1.168
--- src/sys/kern/kern_lock.c:1.167 Fri Jan 24 20:05:15 2020
+++ src/sys/kern/kern_lock.c Mon Jan 27 21:05:43 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_lock.c,v 1.167 2020/01/24 20:05:15 ad Exp $ */
+/* $NetBSD: kern_lock.c,v 1.168 2020/01/27 21:05:43 ad Exp $ */
/*-
* Copyright (c) 2002, 2006, 2007, 2008, 2009, 2020 The NetBSD Foundation, Inc.
@@ -31,7 +31,11 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_lock.c,v 1.167 2020/01/24 20:05:15 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_lock.c,v 1.168 2020/01/27 21:05:43 ad Exp $");
+
+#ifdef _KERNEL_OPT
+#include "opt_lockdebug.h"
+#endif
#include <sys/param.h>
#include <sys/proc.h>
@@ -45,6 +49,10 @@ __KERNEL_RCSID(0, "$NetBSD: kern_lock.c,
#include <sys/lwp.h>
#include <sys/pserialize.h>
+#if defined(DIAGNOSTIC) && !defined(LOCKDEBUG)
+#include <sys/ksyms.h>
+#endif
+
#include <machine/lock.h>
#include <dev/lockstat.h>
@@ -215,6 +223,9 @@ _kernel_lock(int nlocks)
membar_producer();
owant = ci->ci_biglock_wanted;
ci->ci_biglock_wanted = l;
+#if defined(DIAGNOSTIC) && !defined(LOCKDEBUG)
+ l->l_ld_wanted = __builtin_return_address(0);
+#endif
/*
* Spin until we acquire the lock. Once we have it, record the
@@ -330,3 +341,23 @@ _kernel_locked_p(void)
{
return __SIMPLELOCK_LOCKED_P(kernel_lock);
}
+
+void
+kernel_lock_plug_leak(void)
+{
+#ifndef LOCKDEBUG
+# ifdef DIAGNOSTIC
+ int biglocks = 0;
+ KERNEL_UNLOCK_ALL(curlwp, &biglocks);
+ if (biglocks != 0) {
+ const char *sym = "(unknown)";
+ ksyms_getname(NULL, &sym, (vaddr_t)curlwp->l_ld_wanted,
+ KSYMS_CLOSEST|KSYMS_PROC|KSYMS_ANY);
+ printf("kernel_lock leak detected. last acquired: %s / %p\n",
+ sym, curlwp->l_ld_wanted);
+ }
+# else
+ KERNEL_UNLOCK_ALL(curlwp, NULL);
+# endif
+#endif
+}
Index: src/sys/sys/lock.h
diff -u src/sys/sys/lock.h:1.87 src/sys/sys/lock.h:1.88
--- src/sys/sys/lock.h:1.87 Tue Jul 10 19:55:05 2018
+++ src/sys/sys/lock.h Mon Jan 27 21:05:43 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: lock.h,v 1.87 2018/07/10 19:55:05 maya Exp $ */
+/* $NetBSD: lock.h,v 1.88 2020/01/27 21:05:43 ad Exp $ */
/*-
* Copyright (c) 1999, 2000, 2006, 2007 The NetBSD Foundation, Inc.
@@ -109,6 +109,8 @@ do { \
extern __cpu_simple_lock_t kernel_lock[];
+void kernel_lock_plug_leak(void);
+
#endif /* _KERNEL */
#endif /* _SYS_LOCK_H_ */
