The patch titled
Subject: idr: make idr_get_next() good for rcu_read_lock()
has been removed from the -mm tree. Its filename was
idr-make-idr_get_next-good-for-rcu_read_lock.patch
This patch was dropped because it was merged into mainline or a subsystem tree
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
From: Hugh Dickins <hughd@xxxxxxxxxx>
Subject: idr: make idr_get_next() good for rcu_read_lock()
Make one small adjustment to idr_get_next(): take the height from the top
layer (stable under RCU) instead of from the root (unprotected by RCU), as
idr_find() does: so that it can be used with RCU locking. Copied comment
on RCU locking from idr_find().
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Acked-by: Li Zefan <lizf@xxxxxxxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/idr.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff -puN lib/idr.c~idr-make-idr_get_next-good-for-rcu_read_lock lib/idr.c
--- a/lib/idr.c~idr-make-idr_get_next-good-for-rcu_read_lock
+++ a/lib/idr.c
@@ -595,8 +595,10 @@ EXPORT_SYMBOL(idr_for_each);
* Returns pointer to registered object with id, which is next number to
* given id. After being looked up, *@nextidp will be updated for the next
* iteration.
+ *
+ * This function can be called under rcu_read_lock(), given that the leaf
+ * pointers lifetimes are correctly managed.
*/
-
void *idr_get_next(struct idr *idp, int *nextidp)
{
struct idr_layer *p, *pa[MAX_LEVEL];
@@ -605,11 +607,11 @@ void *idr_get_next(struct idr *idp, int
int n, max;
/* find first ent */
- n = idp->layers * IDR_BITS;
- max = 1 << n;
p = rcu_dereference_raw(idp->top);
if (!p)
return NULL;
+ n = (p->layer + 1) * IDR_BITS;
+ max = 1 << n;
while (id < max) {
while (n > 0 && p) {
_
Patches currently in -mm which might be from hughd@xxxxxxxxxx are
origin.patch
linux-next.patch
mm-hugetlb-cleanup-duplicated-code-in-unmapping-vm-range.patch
radix-tree-introduce-bit-optimized-iterator.patch
radix-tree-introduce-bit-optimized-iterator-v3.patch
radix-tree-introduce-bit-optimized-iterator-v3-fix.patch
radix-tree-rewrite-gang-lookup-with-using-iterator.patch
radix-tree-use-iterators-in-find_get_pages-functions.patch
prio_tree-debugging-patch.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
