[fio.git] / engines / cpu.c

/*
 * CPU engine
 *
 * Doesn't transfer any data, merely burns CPU cycles according to
 * the settings.
 *
 */
#include "../fio.h"
#include "../optgroup.h"

struct cpu_options {
	void *pad;
	unsigned int cpuload;
	unsigned int cpucycle;
	unsigned int exit_io_done;
};

static struct fio_option options[] = {
	{
		.name	= "cpuload",
		.lname	= "CPU load",
		.type	= FIO_OPT_INT,
		.off1	= offsetof(struct cpu_options, cpuload),
		.help	= "Use this percentage of CPU",
		.category = FIO_OPT_C_GENERAL,
		.group	= FIO_OPT_G_INVALID,
	},
	{
		.name	= "cpuchunks",
		.lname	= "CPU chunk",
		.type	= FIO_OPT_INT,
		.off1	= offsetof(struct cpu_options, cpucycle),
		.help	= "Length of the CPU burn cycles (usecs)",
		.def	= "50000",
		.parent = "cpuload",
		.hide	= 1,
		.category = FIO_OPT_C_GENERAL,
		.group	= FIO_OPT_G_INVALID,
	},
	{
		.name	= "exit_on_io_done",
		.lname	= "Exit when IO threads are done",
		.type	= FIO_OPT_BOOL,
		.off1	= offsetof(struct cpu_options, exit_io_done),
		.help	= "Exit when IO threads finish",
		.def	= "0",
		.category = FIO_OPT_C_GENERAL,
		.group	= FIO_OPT_G_INVALID,
	},
	{
		.name	= NULL,
	},
};


static int fio_cpuio_queue(struct thread_data *td, struct io_u fio_unused *io_u)
{
	struct cpu_options *co = td->eo;

	if (co->exit_io_done && !fio_running_or_pending_io_threads()) {
		td->done = 1;
		return FIO_Q_BUSY;
	}

	usec_spin(co->cpucycle);
	return FIO_Q_COMPLETED;
}

static int fio_cpuio_init(struct thread_data *td)
{
	struct thread_options *o = &td->o;
	struct cpu_options *co = td->eo;

	if (!co->cpuload) {
		td_vmsg(td, EINVAL, "cpu thread needs rate (cpuload=)","cpuio");
		return 1;
	}

	if (co->cpuload > 100)
		co->cpuload = 100;

	/*
	 * set thinktime_sleep and thinktime_spin appropriately
	 */
	o->thinktime_blocks = 1;
	o->thinktime_spin = 0;
	o->thinktime = (co->cpucycle * (100 - co->cpuload)) / co->cpuload;

	o->nr_files = o->open_files = 1;

	log_info("%s: ioengine=%s, cpuload=%u, cpucycle=%u\n",
		td->o.name, td->io_ops->name, co->cpuload, co->cpucycle);

	return 0;
}

static int fio_cpuio_open(struct thread_data fio_unused *td,
			  struct fio_file fio_unused *f)
{
	return 0;
}

static struct ioengine_ops ioengine = {
	.name		= "cpuio",
	.version	= FIO_IOOPS_VERSION,
	.queue		= fio_cpuio_queue,
	.init		= fio_cpuio_init,
	.open_file	= fio_cpuio_open,
	.flags		= FIO_SYNCIO | FIO_DISKLESSIO | FIO_NOIO,
	.options		= options,
	.option_struct_size	= sizeof(struct cpu_options),
};

static void fio_init fio_cpuio_register(void)
{
	register_ioengine(&ioengine);
}

static void fio_exit fio_cpuio_unregister(void)
{
	unregister_ioengine(&ioengine);
}
Commit	Line	Data
	1	/*
	2	* CPU engine
	3	*
	4	* Doesn't transfer any data, merely burns CPU cycles according to
	5	* the settings.
	6	*
	7	*/
	8	#include "../fio.h"
	9	#include "../optgroup.h"
	10
	11	struct cpu_options {
	12	void *pad;
	13	unsigned int cpuload;
	14	unsigned int cpucycle;
	15	unsigned int exit_io_done;
	16	};
	17
	18	static struct fio_option options[] = {
	19	{
	20	.name = "cpuload",
	21	.lname = "CPU load",
	22	.type = FIO_OPT_INT,
	23	.off1 = offsetof(struct cpu_options, cpuload),
	24	.help = "Use this percentage of CPU",
	25	.category = FIO_OPT_C_GENERAL,
	26	.group = FIO_OPT_G_INVALID,
	27	},
	28	{
	29	.name = "cpuchunks",
	30	.lname = "CPU chunk",
	31	.type = FIO_OPT_INT,
	32	.off1 = offsetof(struct cpu_options, cpucycle),
	33	.help = "Length of the CPU burn cycles (usecs)",
	34	.def = "50000",
	35	.parent = "cpuload",
	36	.hide = 1,
	37	.category = FIO_OPT_C_GENERAL,
	38	.group = FIO_OPT_G_INVALID,
	39	},
	40	{
	41	.name = "exit_on_io_done",
	42	.lname = "Exit when IO threads are done",
	43	.type = FIO_OPT_BOOL,
	44	.off1 = offsetof(struct cpu_options, exit_io_done),
	45	.help = "Exit when IO threads finish",
	46	.def = "0",
	47	.category = FIO_OPT_C_GENERAL,
	48	.group = FIO_OPT_G_INVALID,
	49	},
	50	{
	51	.name = NULL,
	52	},
	53	};
	54
	55
	56	static int fio_cpuio_queue(struct thread_data td, struct io_u fio_unused io_u)
	57	{
	58	struct cpu_options *co = td->eo;
	59
	60	if (co->exit_io_done && !fio_running_or_pending_io_threads()) {
	61	td->done = 1;
	62	return FIO_Q_BUSY;
	63	}
	64
	65	usec_spin(co->cpucycle);
	66	return FIO_Q_COMPLETED;
	67	}
	68
	69	static int fio_cpuio_init(struct thread_data *td)
	70	{
	71	struct thread_options *o = &td->o;
	72	struct cpu_options *co = td->eo;
	73
	74	if (!co->cpuload) {
	75	td_vmsg(td, EINVAL, "cpu thread needs rate (cpuload=)","cpuio");
	76	return 1;
	77	}
	78
	79	if (co->cpuload > 100)
	80	co->cpuload = 100;
	81
	82	/*
	83	* set thinktime_sleep and thinktime_spin appropriately
	84	*/
	85	o->thinktime_blocks = 1;
	86	o->thinktime_spin = 0;
	87	o->thinktime = (co->cpucycle * (100 - co->cpuload)) / co->cpuload;
	88
	89	o->nr_files = o->open_files = 1;
	90
	91	log_info("%s: ioengine=%s, cpuload=%u, cpucycle=%u\n",
	92	td->o.name, td->io_ops->name, co->cpuload, co->cpucycle);
	93
	94	return 0;
	95	}
	96
	97	static int fio_cpuio_open(struct thread_data fio_unused *td,
	98	struct fio_file fio_unused *f)
	99	{
	100	return 0;
	101	}
	102
	103	static struct ioengine_ops ioengine = {
	104	.name = "cpuio",
	105	.version = FIO_IOOPS_VERSION,
	106	.queue = fio_cpuio_queue,
	107	.init = fio_cpuio_init,
	108	.open_file = fio_cpuio_open,
	109	.flags = FIO_SYNCIO \| FIO_DISKLESSIO \| FIO_NOIO,
	110	.options = options,
	111	.option_struct_size = sizeof(struct cpu_options),
	112	};
	113
	114	static void fio_init fio_cpuio_register(void)
	115	{
	116	register_ioengine(&ioengine);
	117	}
	118
	119	static void fio_exit fio_cpuio_unregister(void)
	120	{
	121	unregister_ioengine(&ioengine);
	122	}