XArray: Add xa_store_bh() and xa_store_irq() (84e5acb7) · Commits · 戴 / test

Documentation/core-api/xarray.rst

+4 −1

Original line number	Diff line number	Diff line
		@@ -167,6 +167,8 @@ Takes RCU read lock:

		Takes xa_lock internally:
		* :c:func:`xa_store`
		* :c:func:`xa_store_bh`
		* :c:func:`xa_store_irq`
		* :c:func:`xa_insert`
		* :c:func:`xa_erase`
		* :c:func:`xa_erase_bh`
		@@ -247,7 +249,8 @@ Sharing the XArray with interrupt context is also possible, either
		using :c:func:`xa_lock_irqsave` in both the interrupt handler and process
		context, or :c:func:`xa_lock_irq` in process context and :c:func:`xa_lock`
		in the interrupt handler. Some of the more common patterns have helper
		functions such as :c:func:`xa_erase_bh` and :c:func:`xa_erase_irq`.
		functions such as :c:func:`xa_store_bh`, :c:func:`xa_store_irq`,
		:c:func:`xa_erase_bh` and :c:func:`xa_erase_irq`.

		Sometimes you need to protect access to the XArray with a mutex because
		that lock sits above another mutex in the locking hierarchy. That does

+52 −0

Original line number	Diff line number	Diff line
		@@ -426,6 +426,58 @@ static inline int __xa_insert(struct xarray *xa, unsigned long index,
		return -EEXIST;
		}

		/**
		* xa_store_bh() - Store this entry in the XArray.
		* @xa: XArray.
		* @index: Index into array.
		* @entry: New entry.
		* @gfp: Memory allocation flags.
		*
		* This function is like calling xa_store() except it disables softirqs
		* while holding the array lock.
		*
		* Context: Any context. Takes and releases the xa_lock while
		* disabling softirqs.
		* Return: The entry which used to be at this index.
		*/
		static inline void xa_store_bh(struct xarray xa, unsigned long index,
		void *entry, gfp_t gfp)
		{
		void *curr;

		xa_lock_bh(xa);
		curr = __xa_store(xa, index, entry, gfp);
		xa_unlock_bh(xa);

		return curr;
		}

		/**
		* xa_store_irq() - Erase this entry from the XArray.
		* @xa: XArray.
		* @index: Index into array.
		* @entry: New entry.
		* @gfp: Memory allocation flags.
		*
		* This function is like calling xa_store() except it disables interrupts
		* while holding the array lock.
		*
		* Context: Process context. Takes and releases the xa_lock while
		* disabling interrupts.
		* Return: The entry which used to be at this index.
		*/
		static inline void xa_store_irq(struct xarray xa, unsigned long index,
		void *entry, gfp_t gfp)
		{
		void *curr;

		xa_lock_irq(xa);
		curr = __xa_store(xa, index, entry, gfp);
		xa_unlock_irq(xa);

		return curr;
		}

		/**
		* xa_erase_bh() - Erase this entry from the XArray.
		* @xa: XArray.