diff --git a/Documentation/core-api/xarray.rst b/Documentation/core-api/xarray.rst index 616ac406bf86..dbe96cb5558e 100644 --- a/Documentation/core-api/xarray.rst +++ b/Documentation/core-api/xarray.rst @@ -74,7 +74,8 @@ using :c:func:`xa_load`. xa_store will overwrite any entry with the new entry and return the previous entry stored at that index. You can use :c:func:`xa_erase` instead of calling :c:func:`xa_store` with a ``NULL`` entry. There is no difference between an entry that has never -been stored to and one that has most recently had ``NULL`` stored to it. +been stored to, one that has been erased and one that has most recently +had ``NULL`` stored to it. You can conditionally replace an entry at an index by using :c:func:`xa_cmpxchg`. Like :c:func:`cmpxchg`, it will only succeed if @@ -114,6 +115,9 @@ unused entry. If another user has stored to the entry in the meantime, :c:func:`xa_release` will do nothing; if instead you want the entry to become ``NULL``, you should use :c:func:`xa_erase`. +If all entries in the array are ``NULL``, the :c:func:`xa_empty` function +will return ``true``. + Finally, you can remove all entries from an XArray by calling :c:func:`xa_destroy`. If the XArray entries are pointers, you may wish to free the entries first. You can do this by iterating over all present diff --git a/include/linux/xarray.h b/include/linux/xarray.h index 52d9732e4ec4..564892e19f8c 100644 --- a/include/linux/xarray.h +++ b/include/linux/xarray.h @@ -487,7 +487,7 @@ static inline void *xa_store_irq(struct xarray *xa, unsigned long index, * the third argument. The XArray does not need to allocate memory, so * the user does not need to provide GFP flags. * - * Context: Process context. Takes and releases the xa_lock while + * Context: Any context. Takes and releases the xa_lock while * disabling softirqs. * Return: The entry which used to be at this index. */ @@ -622,7 +622,7 @@ static inline int xa_alloc(struct xarray *xa, u32 *id, u32 max, void *entry, * Updates the @id pointer with the index, then stores the entry at that * index. A concurrent lookup will not see an uninitialised @id. * - * Context: Process context. Takes and releases the xa_lock while + * Context: Any context. Takes and releases the xa_lock while * disabling softirqs. May sleep if the @gfp flags permit. * Return: 0 on success, -ENOMEM if memory allocation fails or -ENOSPC if * there is no more space in the XArray. diff --git a/lib/xarray.c b/lib/xarray.c index c3e2084aa313..7946380cd6c9 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -610,8 +610,8 @@ static int xas_expand(struct xa_state *xas, void *head) * (see the xa_cmpxchg() implementation for an example). * * Return: If the slot already existed, returns the contents of this slot. - * If the slot was newly created, returns NULL. If it failed to create the - * slot, returns NULL and indicates the error in @xas. + * If the slot was newly created, returns %NULL. If it failed to create the + * slot, returns %NULL and indicates the error in @xas. */ static void *xas_create(struct xa_state *xas) { @@ -1640,7 +1640,7 @@ EXPORT_SYMBOL(__xa_alloc); * @index: Index of entry. * @mark: Mark number. * - * Attempting to set a mark on a NULL entry does not succeed. + * Attempting to set a mark on a %NULL entry does not succeed. * * Context: Any context. Expects xa_lock to be held on entry. */ @@ -1710,7 +1710,7 @@ EXPORT_SYMBOL(xa_get_mark); * @index: Index of entry. * @mark: Mark number. * - * Attempting to set a mark on a NULL entry does not succeed. + * Attempting to set a mark on a %NULL entry does not succeed. * * Context: Process context. Takes and releases the xa_lock. */ @@ -1879,7 +1879,7 @@ static unsigned int xas_extract_marked(struct xa_state *xas, void **dst, * * The @filter may be an XArray mark value, in which case entries which are * marked with that mark will be copied. It may also be %XA_PRESENT, in - * which case all entries which are not NULL will be copied. + * which case all entries which are not %NULL will be copied. * * The entries returned may not represent a snapshot of the XArray at a * moment in time. For example, if another thread stores to index 5, then