Module Name: src
Committed By: riastradh
Date: Wed Jul 24 01:56:48 UTC 2013
Modified Files:
src/sys/external/bsd/drm2/linux [riastradh-drm2]: linux_idr.c
Log Message:
In linux_idr, move idr_temp access under the write lock.
The atomic swaps were missing memory barriers, but using the rwlock
is easier to understand for now. This should probably use passive
serialization eventually anyway.
To generate a diff of this commit:
cvs rdiff -u -r1.1.2.1 -r1.1.2.2 src/sys/external/bsd/drm2/linux/linux_idr.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/external/bsd/drm2/linux/linux_idr.c
diff -u src/sys/external/bsd/drm2/linux/linux_idr.c:1.1.2.1 src/sys/external/bsd/drm2/linux/linux_idr.c:1.1.2.2
--- src/sys/external/bsd/drm2/linux/linux_idr.c:1.1.2.1 Wed Jul 24 00:50:36 2013
+++ src/sys/external/bsd/drm2/linux/linux_idr.c Wed Jul 24 01:56:48 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_idr.c,v 1.1.2.1 2013/07/24 00:50:36 riastradh Exp $ */
+/* $NetBSD: linux_idr.c,v 1.1.2.2 2013/07/24 01:56:48 riastradh Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_idr.c,v 1.1.2.1 2013/07/24 00:50:36 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_idr.c,v 1.1.2.2 2013/07/24 01:56:48 riastradh Exp $");
#include <sys/param.h>
#include <sys/atomic.h>
@@ -142,8 +142,12 @@ idr_pre_get(struct idr *idr, int flags _
if (temp == NULL)
return 0;
- if (atomic_cas_ptr(&idr->idr_temp, NULL, temp) != NULL)
+ rw_enter(&idr->idr_lock, RW_WRITER);
+ if (idr->idr_temp == NULL)
+ idr->idr_temp = temp;
+ else
kmem_free(temp, sizeof(*temp));
+ rw_exit(&idr->idr_lock);
return 1;
}
@@ -154,12 +158,15 @@ idr_get_new_above(struct idr *idr, void
struct idr_node *node, *search, *collision __unused;
int want_id = min_id;
- node = atomic_swap_ptr(&idr->idr_temp, NULL);
- if (node == NULL)
- return -EAGAIN;
-
rw_enter(&idr->idr_lock, RW_WRITER);
+ node = idr->idr_temp;
+ if (node == NULL) {
+ rw_exit(&idr->idr_lock);
+ return -EAGAIN;
+ }
+ idr->idr_temp = NULL;
+
search = rb_tree_find_node_geq(&idr->idr_tree, &min_id);
while ((search != NULL) && (search->in_index == want_id)) {
search = rb_tree_iterate(&idr->idr_tree, search, RB_DIR_RIGHT);
