ring-buffer: pass in lockdep class key for reader_lock

 * size is in bytes for each per CPU buffer.

 */

struct ring_buffer *

ring_buffer_alloc(unsigned long size, unsigned flags);

__ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key);

/*

 * Because the ring buffer is generic, if other users of the ring buffer get

 * traced by ftrace, it can produce lockdep warnings. We need to keep each

 * ring buffer's lock class separate.

 */

#define ring_buffer_alloc(size, flags)			\

({							\

	static struct lock_class_key __key;		\

	__ring_buffer_alloc((size), (flags), &__key);	\

})

void ring_buffer_free(struct ring_buffer *buffer);

int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size);

	atomic_t			record_disabled;

	cpumask_var_t			cpumask;

	struct lock_class_key		*reader_lock_key;

	struct mutex			mutex;

	struct ring_buffer_per_cpu	**buffers;

	cpu_buffer->cpu = cpu;

	cpu_buffer->buffer = buffer;

	spin_lock_init(&cpu_buffer->reader_lock);

	lockdep_set_class(&cpu_buffer->reader_lock, buffer->reader_lock_key);

	cpu_buffer->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;

	INIT_LIST_HEAD(&cpu_buffer->pages);

 * when the buffer wraps. If this flag is not set, the buffer will

 * drop data when the tail hits the head.

 */

struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags)

struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,

					struct lock_class_key *key)

{

	struct ring_buffer *buffer;

	int bsize;

	buffer->pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);

	buffer->flags = flags;

	buffer->clock = trace_clock_local;

	buffer->reader_lock_key = key;

	/* need at least two pages */

	if (buffer->pages == 1)

	kfree(buffer);

	return NULL;

}

EXPORT_SYMBOL_GPL(ring_buffer_alloc);

EXPORT_SYMBOL_GPL(__ring_buffer_alloc);

/**

 * ring_buffer_free - free a ring buffer.