tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers

void trace_printk_init_buffers(void);

int trace_array_printk(struct trace_array *tr, unsigned long ip,

		const char *fmt, ...);

int trace_array_init_printk(struct trace_array *tr);

void trace_array_put(struct trace_array *tr);

struct trace_array *trace_array_get_by_name(const char *name);

int trace_array_destroy(struct trace_array *tr);

{

	struct trace_buffer_struct *buffers;

	if (trace_percpu_buffer)

		return 0;

	buffers = alloc_percpu(struct trace_buffer_struct);

	if (MEM_FAIL(!buffers, "Could not allocate percpu trace_printk buffer"))

		return -ENOMEM;

	return __trace_array_vprintk(tr->array_buffer.buffer, ip, fmt, args);

}

/**

 * trace_array_printk - Print a message to a specific instance

 * @tr: The instance trace_array descriptor

 * @ip: The instruction pointer that this is called from.

 * @fmt: The format to print (printf format)

 *

 * If a subsystem sets up its own instance, they have the right to

 * printk strings into their tracing instance buffer using this

 * function. Note, this function will not write into the top level

 * buffer (use trace_printk() for that), as writing into the top level

 * buffer should only have events that can be individually disabled.

 * trace_printk() is only used for debugging a kernel, and should not

 * be ever encorporated in normal use.

 *

 * trace_array_printk() can be used, as it will not add noise to the

 * top level tracing buffer.

 *

 * Note, trace_array_init_printk() must be called on @tr before this

 * can be used.

 */

__printf(3, 0)

int trace_array_printk(struct trace_array *tr,

		       unsigned long ip, const char *fmt, ...)

}

EXPORT_SYMBOL_GPL(trace_array_printk);

/**

 * trace_array_init_printk - Initialize buffers for trace_array_printk()

 * @tr: The trace array to initialize the buffers for

 *

 * As trace_array_printk() only writes into instances, they are OK to

 * have in the kernel (unlike trace_printk()). This needs to be called

 * before trace_array_printk() can be used on a trace_array.

 */

int trace_array_init_printk(struct trace_array *tr)

{

	if (!tr)

		return -ENOENT;

	/* This is only allowed for created instances */

	if (tr == &global_trace)

		return -EINVAL;

	return alloc_percpu_trace_buffer();

}

EXPORT_SYMBOL_GPL(trace_array_init_printk);

__printf(3, 4)

int trace_array_printk_buf(struct trace_buffer *buffer,

			   unsigned long ip, const char *fmt, ...)