kfifo: provide noirqsave variants of spinlocked in and out helpers
authorBartosz Golaszewski <bgolaszewski@baylibre.com>
Tue, 17 Dec 2019 17:48:55 +0000 (18:48 +0100)
committerBartosz Golaszewski <bgolaszewski@baylibre.com>
Wed, 12 Feb 2020 11:05:46 +0000 (12:05 +0100)
Provide variants of spinlocked kfifo_in() and kfifo_out() routines which
don't disable interrupts.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Stefani Seibold <stefani@seibold.net>
include/linux/kfifo.h

index fc4b0b10210f4a4c1ede9e588d2f8dba65ebc71b..123c200ed7cb11a24035f6e46ff12771016c1677 100644 (file)
@@ -517,6 +517,26 @@ __kfifo_uint_must_check_helper( \
        __ret; \
 })
 
+/**
+ * kfifo_in_spinlocked_noirqsave - put data into fifo using a spinlock for
+ * locking, don't disable interrupts
+ * @fifo: address of the fifo to be used
+ * @buf: the data to be added
+ * @n: number of elements to be added
+ * @lock: pointer to the spinlock to use for locking
+ *
+ * This is a variant of kfifo_in_spinlocked() but uses spin_lock/unlock()
+ * for locking and doesn't disable interrupts.
+ */
+#define kfifo_in_spinlocked_noirqsave(fifo, buf, n, lock) \
+({ \
+       unsigned int __ret; \
+       spin_lock(lock); \
+       __ret = kfifo_in(fifo, buf, n); \
+       spin_unlock(lock); \
+       __ret; \
+})
+
 /* alias for kfifo_in_spinlocked, will be removed in a future release */
 #define kfifo_in_locked(fifo, buf, n, lock) \
                kfifo_in_spinlocked(fifo, buf, n, lock)
@@ -569,6 +589,28 @@ __kfifo_uint_must_check_helper( \
 }) \
 )
 
+/**
+ * kfifo_out_spinlocked_noirqsave - get data from the fifo using a spinlock
+ * for locking, don't disable interrupts
+ * @fifo: address of the fifo to be used
+ * @buf: pointer to the storage buffer
+ * @n: max. number of elements to get
+ * @lock: pointer to the spinlock to use for locking
+ *
+ * This is a variant of kfifo_out_spinlocked() which uses spin_lock/unlock()
+ * for locking and doesn't disable interrupts.
+ */
+#define kfifo_out_spinlocked_noirqsave(fifo, buf, n, lock) \
+__kfifo_uint_must_check_helper( \
+({ \
+       unsigned int __ret; \
+       spin_lock(lock); \
+       __ret = kfifo_out(fifo, buf, n); \
+       spin_unlock(lock); \
+       __ret; \
+}) \
+)
+
 /* alias for kfifo_out_spinlocked, will be removed in a future release */
 #define kfifo_out_locked(fifo, buf, n, lock) \
                kfifo_out_spinlocked(fifo, buf, n, lock)