Module Name: src
Committed By: riastradh
Date: Sun Dec 19 11:39:00 UTC 2021
Modified Files:
src/sys/external/bsd/drm2/include/linux: kref.h
Log Message:
Provide kref_put_lock
Author: Maya Rashish <m...@netbsd.org>
Committer: Taylor R Campbell <riastr...@netbsd.org>
To generate a diff of this commit:
cvs rdiff -u -r1.10 -r1.11 src/sys/external/bsd/drm2/include/linux/kref.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/external/bsd/drm2/include/linux/kref.h
diff -u src/sys/external/bsd/drm2/include/linux/kref.h:1.10 src/sys/external/bsd/drm2/include/linux/kref.h:1.11
--- src/sys/external/bsd/drm2/include/linux/kref.h:1.10 Sun Dec 19 10:48:37 2021
+++ src/sys/external/bsd/drm2/include/linux/kref.h Sun Dec 19 11:39:00 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: kref.h,v 1.10 2021/12/19 10:48:37 riastradh Exp $ */
+/* $NetBSD: kref.h,v 1.11 2021/12/19 11:39:00 riastradh Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -39,6 +39,7 @@
#include <linux/atomic.h>
#include <linux/refcount.h>
#include <linux/mutex.h>
+#include <linux/spinlock.h>
struct kref {
unsigned int kr_count;
@@ -107,6 +108,33 @@ kref_sub(struct kref *kref, unsigned int
}
static inline int
+kref_put_lock(struct kref *kref, void (*release)(struct kref *), spinlock_t *interlock)
+{
+ unsigned int old, new;
+
+#ifndef __HAVE_ATOMIC_AS_MEMBAR
+ membar_exit();
+#endif
+
+ do {
+ old = kref->kr_count;
+ KASSERT(old > 0);
+ if (old == 1) {
+ spin_lock(interlock);
+ if (atomic_add_int_nv(&kref->kr_count, -1) == 0) {
+ (*release)(kref);
+ return 1;
+ }
+ spin_unlock(interlock);
+ return 0;
+ }
+ new = (old - 1);
+ } while (atomic_cas_uint(&kref->kr_count, old, new) != old);
+
+ return 0;
+}
+
+static inline int
kref_put(struct kref *kref, void (*release)(struct kref *))
{
