diff options
Diffstat (limited to 'app/test/test_cycles.c')
-rw-r--r-- | app/test/test_cycles.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/app/test/test_cycles.c b/app/test/test_cycles.c new file mode 100644 index 00000000..d8fa5171 --- /dev/null +++ b/app/test/test_cycles.c @@ -0,0 +1,96 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2010-2014 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <stdio.h> +#include <stdint.h> + +#include <rte_common.h> +#include <rte_cycles.h> + +#include "test.h" + +#define N 10000 + +/* + * Cycles test + * =========== + * + * - Loop N times and check that the timer always increments and + * never decrements during this loop. + * + * - Wait one second using rte_usleep() and check that the increment + * of cycles is correct with regard to the frequency of the timer. + */ + +static int +test_cycles(void) +{ + unsigned i; + uint64_t start_cycles, cycles, prev_cycles; + uint64_t hz = rte_get_timer_hz(); + uint64_t max_inc = (hz / 100); /* 10 ms max between 2 reads */ + + /* check that the timer is always incrementing */ + start_cycles = rte_get_timer_cycles(); + prev_cycles = start_cycles; + for (i=0; i<N; i++) { + cycles = rte_get_timer_cycles(); + if ((uint64_t)(cycles - prev_cycles) > max_inc) { + printf("increment too high or going backwards\n"); + return -1; + } + prev_cycles = cycles; + } + + /* check that waiting 1 second is precise */ + prev_cycles = rte_get_timer_cycles(); + rte_delay_us(1000000); + cycles = rte_get_timer_cycles(); + + if ((uint64_t)(cycles - prev_cycles) > (hz + max_inc)) { + printf("delay_us is not accurate: too long\n"); + return -1; + } + if ((uint64_t)(cycles - prev_cycles) < (hz - max_inc)) { + printf("delay_us is not accurate: too short\n"); + return -1; + } + + return 0; +} + +static struct test_command cycles_cmd = { + .command = "cycles_autotest", + .callback = test_cycles, +}; +REGISTER_TEST_COMMAND(cycles_cmd); |