+/*
+ * CPU engine
+ *
+ * Doesn't transfer any data, merely burns CPU cycles according to
+ * the settings.
+ *
+ */
#include "../fio.h"
-#include "../os.h"
+#include "../optgroup.h"
-static int fio_cpuio_setup(struct thread_data fio_unused *td)
+// number of 32 bit integers to sort
+size_t qsort_size = (256 * (1ULL << 10)); // 256KB
+
+struct mwc {
+ uint32_t w;
+ uint32_t z;
+};
+
+enum stress_mode {
+ FIO_CPU_NOOP = 0,
+ FIO_CPU_QSORT = 1,
+};
+
+struct cpu_options {
+ void *pad;
+ unsigned int cpuload;
+ unsigned int cpucycle;
+ enum stress_mode cpumode;
+ unsigned int exit_io_done;
+ int32_t *qsort_data;
+};
+
+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_ENGINE,
+ .group = FIO_OPT_G_INVALID,
+ },
+ {
+ .name = "cpumode",
+ .lname = "cpumode",
+ .type = FIO_OPT_STR,
+ .help = "Stress mode",
+ .off1 = offsetof(struct cpu_options, cpumode),
+ .def = "noop",
+ .posval = {
+ { .ival = "noop",
+ .oval = FIO_CPU_NOOP,
+ .help = "NOOP instructions",
+ },
+ { .ival = "qsort",
+ .oval = FIO_CPU_QSORT,
+ .help = "QSORT computation",
+ },
+ },
+ .category = FIO_OPT_C_ENGINE,
+ .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_ENGINE,
+ .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_ENGINE,
+ .group = FIO_OPT_G_INVALID,
+ },
+ {
+ .name = NULL,
+ },
+};
+
+/*
+ * mwc32()
+ * Multiply-with-carry random numbers
+ * fast pseudo random number generator, see
+ * http://www.cse.yorku.ca/~oz/marsaglia-rng.html
+ */
+uint32_t mwc32(struct mwc *mwc)
+{
+ mwc->z = 36969 * (mwc->z & 65535) + (mwc->z >> 16);
+ mwc->w = 18000 * (mwc->w & 65535) + (mwc->w >> 16);
+ return (mwc->z << 16) + mwc->w;
+}
+
+/*
+ * stress_qsort_cmp_1()
+ * qsort comparison - sort on int32 values
+ */
+static int stress_qsort_cmp_1(const void *p1, const void *p2)
+{
+ const int32_t *i1 = (const int32_t *)p1;
+ const int32_t *i2 = (const int32_t *)p2;
+
+ if (*i1 > *i2)
+ return 1;
+ else if (*i1 < *i2)
+ return -1;
+ else
+ return 0;
+}
+
+/*
+ * stress_qsort_cmp_2()
+ * qsort comparison - reverse sort on int32 values
+ */
+static int stress_qsort_cmp_2(const void *p1, const void *p2)
+{
+ return stress_qsort_cmp_1(p2, p1);
+}
+
+/*
+ * stress_qsort_cmp_3()
+ * qsort comparison - sort on int8 values
+ */
+static int stress_qsort_cmp_3(const void *p1, const void *p2)
+{
+ const int8_t *i1 = (const int8_t *)p1;
+ const int8_t *i2 = (const int8_t *)p2;
+
+ /* Force re-ordering on 8 bit value */
+ return *i1 - *i2;
+}
+
+static int do_qsort(struct thread_data *td)
+{
+ struct thread_options *o = &td->o;
+ struct cpu_options *co = td->eo;
+ struct timespec start, now;
+
+ fio_get_mono_time(&start);
+
+ /* Sort "random" data */
+ qsort(co->qsort_data, qsort_size, sizeof(*(co->qsort_data)), stress_qsort_cmp_1);
+
+ /* Reverse sort */
+ qsort(co->qsort_data, qsort_size, sizeof(*(co->qsort_data)), stress_qsort_cmp_2);
+
+ /* And re-order by byte compare */
+ qsort((uint8_t *)co->qsort_data, qsort_size * 4, sizeof(uint8_t), stress_qsort_cmp_3);
+
+ /* Reverse sort this again */
+ qsort(co->qsort_data, qsort_size, sizeof(*(co->qsort_data)), stress_qsort_cmp_2);
+ fio_get_mono_time(&now);
+
+ /* Adjusting cpucycle automatically to be as close as possible to the
+ * expected cpuload The time to execute do_qsort() may change over time
+ * as per : - the job concurrency - the cpu clock adjusted by the power
+ * management After every do_qsort() call, the next thinktime is
+ * adjusted regarding the last run performance
+ */
+ co->cpucycle = utime_since(&start, &now);
+ o->thinktime = ((unsigned long long) co->cpucycle *
+ (100 - co->cpuload)) / co->cpuload;
+
+ return 0;
+}
+
+static enum fio_q_status 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;
+ }
+
+ switch (co->cpumode) {
+ case FIO_CPU_NOOP:
+ usec_spin(co->cpucycle);
+ break;
+ case FIO_CPU_QSORT:
+ do_qsort(td);
+ break;
+ }
+
+ return FIO_Q_COMPLETED;
+}
+
+static int noop_init(struct thread_data *td)
+{
+ struct cpu_options *co = td->eo;
+
+ log_info("%s (noop): ioengine=%s, cpuload=%u, cpucycle=%u\n",
+ td->o.name, td->io_ops->name, co->cpuload, co->cpucycle);
+ return 0;
+}
+
+static int qsort_cleanup(struct thread_data *td)
{
+ struct cpu_options *co = td->eo;
+
+ if (co->qsort_data) {
+ free(co->qsort_data);
+ co->qsort_data = NULL;
+ }
+
+ return 0;
+}
+
+static int qsort_init(struct thread_data *td)
+{
+ /* Setting up a default entropy */
+ struct mwc mwc = { 521288629UL, 362436069UL };
+ struct cpu_options *co = td->eo;
+ int32_t *ptr;
+ int i;
+
+ co->qsort_data = calloc(qsort_size, sizeof(*co->qsort_data));
+ if (co->qsort_data == NULL) {
+ td_verror(td, ENOMEM, "qsort_init");
+ return 1;
+ }
+
+ /* This is expensive, init the memory once */
+ for (ptr = co->qsort_data, i = 0; i < qsort_size; i++)
+ *ptr++ = mwc32(&mwc);
+
+ log_info("%s (qsort): ioengine=%s, cpuload=%u, cpucycle=%u\n",
+ td->o.name, td->io_ops->name, co->cpuload, co->cpucycle);
+
return 0;
}
static int fio_cpuio_init(struct thread_data *td)
{
- if (!td->cpuload) {
- td_vmsg(td, EINVAL, "cpu thread needs rate");
+ struct thread_options *o = &td->o;
+ struct cpu_options *co = td->eo;
+ int td_previous_state;
+ char *msg;
+
+ if (!co->cpuload) {
+ td_vmsg(td, EINVAL, "cpu thread needs rate (cpuload=)","cpuio");
+ return 1;
+ }
+
+ if (co->cpuload > 100)
+ co->cpuload = 100;
+
+ /* Saving the current thread state */
+ td_previous_state = td->runstate;
+
+ /* Reporting that we are preparing the engine
+ * This is useful as the qsort() calibration takes time
+ * This prevents the job from starting before init is completed
+ */
+ td_set_runstate(td, TD_SETTING_UP);
+
+ /*
+ * set thinktime_sleep and thinktime_spin appropriately
+ */
+ o->thinktime_blocks = 1;
+ o->thinktime_blocks_type = THINKTIME_BLOCKS_TYPE_COMPLETE;
+ o->thinktime_spin = 0;
+ o->thinktime = ((unsigned long long) co->cpucycle *
+ (100 - co->cpuload)) / co->cpuload;
+
+ o->nr_files = o->open_files = 1;
+
+ switch (co->cpumode) {
+ case FIO_CPU_NOOP:
+ noop_init(td);
+ break;
+ case FIO_CPU_QSORT:
+ qsort_init(td);
+ break;
+ default:
+ if (asprintf(&msg, "bad cpu engine mode: %d", co->cpumode) < 0)
+ msg = NULL;
+ td_vmsg(td, EINVAL, msg ? : "(?)", __func__);
+ free(msg);
return 1;
- } else if (td->cpuload > 100)
- td->cpuload = 100;
+ }
- td->nr_files = 0;
+ /* Let's restore the previous state. */
+ td_set_runstate(td, td_previous_state);
+ return 0;
+}
+static void fio_cpuio_cleanup(struct thread_data *td)
+{
+ struct cpu_options *co = td->eo;
+
+ switch (co->cpumode) {
+ case FIO_CPU_NOOP:
+ break;
+ case FIO_CPU_QSORT:
+ qsort_cleanup(td);
+ break;
+ }
+}
+
+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,
- .init = fio_cpuio_init,
- .setup = fio_cpuio_setup,
- .flags = FIO_CPUIO | FIO_NULLIO,
+ .name = "cpuio",
+ .version = FIO_IOOPS_VERSION,
+ .queue = fio_cpuio_queue,
+ .init = fio_cpuio_init,
+ .cleanup = fio_cpuio_cleanup,
+ .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)