+ xarray-fix-kerneldoc-for-__xa_cmpxchg.patch added to mm-unstable branch

+ xarray-fix-kerneldoc-for-__xa_cmpxchg.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: xarray: fix kerneldoc for __xa_cmpxchg
has been added to the -mm mm-unstable branch.  Its filename is
     xarray-fix-kerneldoc-for-__xa_cmpxchg.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/xarray-fix-kerneldoc-for-__xa_cmpxchg.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Christoph Hellwig <hch@lst.de>
Subject: xarray: fix kerneldoc for __xa_cmpxchg
Date: Wed, 7 May 2025 07:16:20 +0200

Fix the documentation for __xa_cmpxchg to actually describe the
cmpxch-like semantics correctly, based on the version for xa_cmpxchg.

Link: https://lkml.kernel.org/r/20250507051656.3900864-1-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/xarray.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/lib/xarray.c~xarray-fix-kerneldoc-for-__xa_cmpxchg
+++ a/lib/xarray.c
@@ -1742,20 +1742,23 @@ static inline void *__xa_cmpxchg_raw(str
 			void *old, void *entry, gfp_t gfp);
 
 /**
- * __xa_cmpxchg() - Store this entry in the XArray.
+ * __xa_cmpxchg() - Conditionally replace an entry in the XArray.
  * @xa: XArray.
  * @index: Index into array.
  * @old: Old value to test against.
- * @entry: New entry.
+ * @entry: New value to place in array.
  * @gfp: Memory allocation flags.
  *
  * You must already be holding the xa_lock when calling this function.
  * It will drop the lock if needed to allocate memory, and then reacquire
  * it afterwards.
  *
+ * If the entry at @index is the same as @old, replace it with @entry.
+ * If the return value is equal to @old, then the exchange was successful.
+ *
  * Context: Any context.  Expects xa_lock to be held on entry.  May
  * release and reacquire xa_lock if @gfp flags permit.
- * Return: The old entry at this index or xa_err() if an error happened.
+ * Return: The old value at this index or xa_err() if an error happened.
  */
 void *__xa_cmpxchg(struct xarray *xa, unsigned long index,
 			void *old, void *entry, gfp_t gfp)
_

Patches currently in -mm which might be from hch@lst.de are

xarray-fix-kerneldoc-for-__xa_cmpxchg.patch