throttle: Add units tests

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 481 insertions, 0 deletions

diff --git a/tests/test-throttle.c b/tests/test-throttle.c
new file mode 100644
index 0000000000..760812645b
--- /dev/null
+++ b/tests/test-throttle.c
@@ -0,0 +1,481 @@
+/*
+ * Throttle infrastructure tests
+ *
+ * Copyright Nodalink, SARL. 2013
+ *
+ * Authors:
+ *  Benoît Canet     <benoit.canet@irqsave.net>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ */
+
+#include <glib.h>
+#include <math.h>
+#include "qemu/throttle.h"
+
+LeakyBucket    bkt;
+ThrottleConfig cfg;
+ThrottleState  ts;
+
+/* usefull function */
+static bool double_cmp(double x, double y)
+{
+    return fabsl(x - y) < 1e-6;
+}
+
+/* tests for single bucket operations */
+static void test_leak_bucket(void)
+{
+    /* set initial value */
+    bkt.avg = 150;
+    bkt.max = 15;
+    bkt.level = 1.5;
+
+    /* leak an op work of time */
+    throttle_leak_bucket(&bkt, NANOSECONDS_PER_SECOND / 150);
+    g_assert(bkt.avg == 150);
+    g_assert(bkt.max == 15);
+    g_assert(double_cmp(bkt.level, 0.5));
+
+    /* leak again emptying the bucket */
+    throttle_leak_bucket(&bkt, NANOSECONDS_PER_SECOND / 150);
+    g_assert(bkt.avg == 150);
+    g_assert(bkt.max == 15);
+    g_assert(double_cmp(bkt.level, 0));
+
+    /* check that the bucket level won't go lower */
+    throttle_leak_bucket(&bkt, NANOSECONDS_PER_SECOND / 150);
+    g_assert(bkt.avg == 150);
+    g_assert(bkt.max == 15);
+    g_assert(double_cmp(bkt.level, 0));
+}
+
+static void test_compute_wait(void)
+{
+    int64_t wait;
+    int64_t result;
+
+    /* no operation limit set */
+    bkt.avg = 0;
+    bkt.max = 15;
+    bkt.level = 1.5;
+    wait = throttle_compute_wait(&bkt);
+    g_assert(!wait);
+
+    /* zero delta */
+    bkt.avg = 150;
+    bkt.max = 15;
+    bkt.level = 15;
+    wait = throttle_compute_wait(&bkt);
+    g_assert(!wait);
+
+    /* below zero delta */
+    bkt.avg = 150;
+    bkt.max = 15;
+    bkt.level = 9;
+    wait = throttle_compute_wait(&bkt);
+    g_assert(!wait);
+
+    /* half an operation above max */
+    bkt.avg = 150;
+    bkt.max = 15;
+    bkt.level = 15.5;
+    wait = throttle_compute_wait(&bkt);
+    /* time required to do half an operation */
+    result = (int64_t)  NANOSECONDS_PER_SECOND / 150 / 2;
+    g_assert(wait == result);
+}
+
+/* functions to test ThrottleState initialization/destroy methods */
+static void read_timer_cb(void *opaque)
+{
+}
+
+static void write_timer_cb(void *opaque)
+{
+}
+
+static void test_init(void)
+{
+    int i;
+
+    /* fill the structure with crap */
+    memset(&ts, 1, sizeof(ts));
+
+    /* init the structure */
+    throttle_init(&ts, QEMU_CLOCK_VIRTUAL, read_timer_cb, write_timer_cb, &ts);
+
+    /* check initialized fields */
+    g_assert(ts.clock_type == QEMU_CLOCK_VIRTUAL);
+    g_assert(ts.timers[0]);
+    g_assert(ts.timers[1]);
+
+    /* check other fields where cleared */
+    g_assert(!ts.previous_leak);
+    g_assert(!ts.cfg.op_size);
+    for (i = 0; i < BUCKETS_COUNT; i++) {
+        g_assert(!ts.cfg.buckets[i].avg);
+        g_assert(!ts.cfg.buckets[i].max);
+        g_assert(!ts.cfg.buckets[i].level);
+    }
+
+    throttle_destroy(&ts);
+}
+
+static void test_destroy(void)
+{
+    int i;
+    throttle_init(&ts, QEMU_CLOCK_VIRTUAL, read_timer_cb, write_timer_cb, &ts);
+    throttle_destroy(&ts);
+    for (i = 0; i < 2; i++) {
+        g_assert(!ts.timers[i]);
+    }
+}
+
+/* function to test throttle_config and throttle_get_config */
+static void test_config_functions(void)
+{
+    int i;
+    ThrottleConfig orig_cfg, final_cfg;
+
+    orig_cfg.buckets[THROTTLE_BPS_TOTAL].avg = 153;
+    orig_cfg.buckets[THROTTLE_BPS_READ].avg  = 56;
+    orig_cfg.buckets[THROTTLE_BPS_WRITE].avg = 1;
+
+    orig_cfg.buckets[THROTTLE_OPS_TOTAL].avg = 150;
+    orig_cfg.buckets[THROTTLE_OPS_READ].avg  = 69;
+    orig_cfg.buckets[THROTTLE_OPS_WRITE].avg = 23;
+
+    orig_cfg.buckets[THROTTLE_BPS_TOTAL].max = 0; /* should be corrected */
+    orig_cfg.buckets[THROTTLE_BPS_READ].max  = 1; /* should not be corrected */
+    orig_cfg.buckets[THROTTLE_BPS_WRITE].max = 120;
+
+    orig_cfg.buckets[THROTTLE_OPS_TOTAL].max = 150;
+    orig_cfg.buckets[THROTTLE_OPS_READ].max  = 400;
+    orig_cfg.buckets[THROTTLE_OPS_WRITE].max = 500;
+
+    orig_cfg.buckets[THROTTLE_BPS_TOTAL].level = 45;
+    orig_cfg.buckets[THROTTLE_BPS_READ].level  = 65;
+    orig_cfg.buckets[THROTTLE_BPS_WRITE].level = 23;
+
+    orig_cfg.buckets[THROTTLE_OPS_TOTAL].level = 1;
+    orig_cfg.buckets[THROTTLE_OPS_READ].level  = 90;
+    orig_cfg.buckets[THROTTLE_OPS_WRITE].level = 75;
+
+    orig_cfg.op_size = 1;
+
+    throttle_init(&ts, QEMU_CLOCK_VIRTUAL, read_timer_cb, write_timer_cb, &ts);
+    /* structure reset by throttle_init previous_leak should be null */
+    g_assert(!ts.previous_leak);
+    throttle_config(&ts, &orig_cfg);
+
+    /* has previous leak been initialized by throttle_config ? */
+    g_assert(ts.previous_leak);
+
+    /* get back the fixed configuration */
+    throttle_get_config(&ts, &final_cfg);
+
+    throttle_destroy(&ts);
+
+    g_assert(final_cfg.buckets[THROTTLE_BPS_TOTAL].avg == 153);
+    g_assert(final_cfg.buckets[THROTTLE_BPS_READ].avg  == 56);
+    g_assert(final_cfg.buckets[THROTTLE_BPS_WRITE].avg == 1);
+
+    g_assert(final_cfg.buckets[THROTTLE_OPS_TOTAL].avg == 150);
+    g_assert(final_cfg.buckets[THROTTLE_OPS_READ].avg  == 69);
+    g_assert(final_cfg.buckets[THROTTLE_OPS_WRITE].avg == 23);
+
+    g_assert(final_cfg.buckets[THROTTLE_BPS_TOTAL].max == 15.3);/* fixed */
+    g_assert(final_cfg.buckets[THROTTLE_BPS_READ].max  == 1);   /* not fixed */
+    g_assert(final_cfg.buckets[THROTTLE_BPS_WRITE].max == 120);
+
+    g_assert(final_cfg.buckets[THROTTLE_OPS_TOTAL].max == 150);
+    g_assert(final_cfg.buckets[THROTTLE_OPS_READ].max  == 400);
+    g_assert(final_cfg.buckets[THROTTLE_OPS_WRITE].max == 500);
+
+    g_assert(final_cfg.op_size == 1);
+
+    /* check bucket have been cleared */
+    for (i = 0; i < BUCKETS_COUNT; i++) {
+        g_assert(!final_cfg.buckets[i].level);
+    }
+}
+
+/* functions to test is throttle is enabled by a config */
+static void set_cfg_value(bool is_max, int index, int value)
+{
+    if (is_max) {
+        cfg.buckets[index].max = value;
+    } else {
+        cfg.buckets[index].avg = value;
+    }
+}
+
+static void test_enabled(void)
+{
+    int i;
+
+    memset(&cfg, 0, sizeof(cfg));
+    g_assert(!throttle_enabled(&cfg));
+
+    for (i = 0; i < BUCKETS_COUNT; i++) {
+        memset(&cfg, 0, sizeof(cfg));
+        set_cfg_value(false, i, 150);
+        g_assert(throttle_enabled(&cfg));
+    }
+
+    for (i = 0; i < BUCKETS_COUNT; i++) {
+        memset(&cfg, 0, sizeof(cfg));
+        set_cfg_value(false, i, -150);
+        g_assert(!throttle_enabled(&cfg));
+    }
+}
+
+/* tests functions for throttle_conflicting */
+
+static void test_conflicts_for_one_set(bool is_max,
+                                       int total,
+                                       int read,
+                                       int write)
+{
+    memset(&cfg, 0, sizeof(cfg));
+    g_assert(!throttle_conflicting(&cfg));
+
+    set_cfg_value(is_max, total, 1);
+    set_cfg_value(is_max, read,  1);
+    g_assert(throttle_conflicting(&cfg));
+
+    memset(&cfg, 0, sizeof(cfg));
+    set_cfg_value(is_max, total, 1);
+    set_cfg_value(is_max, write, 1);
+    g_assert(throttle_conflicting(&cfg));
+
+    memset(&cfg, 0, sizeof(cfg));
+    set_cfg_value(is_max, total, 1);
+    set_cfg_value(is_max, read,  1);
+    set_cfg_value(is_max, write, 1);
+    g_assert(throttle_conflicting(&cfg));
+
+    memset(&cfg, 0, sizeof(cfg));
+    set_cfg_value(is_max, total, 1);
+    g_assert(!throttle_conflicting(&cfg));
+
+    memset(&cfg, 0, sizeof(cfg));
+    set_cfg_value(is_max, read,  1);
+    set_cfg_value(is_max, write, 1);
+    g_assert(!throttle_conflicting(&cfg));
+}
+
+static void test_conflicting_config(void)
+{
+    /* bps average conflicts */
+    test_conflicts_for_one_set(false,
+                               THROTTLE_BPS_TOTAL,
+                               THROTTLE_BPS_READ,
+                               THROTTLE_BPS_WRITE);
+
+    /* ops average conflicts */
+    test_conflicts_for_one_set(false,
+                               THROTTLE_OPS_TOTAL,
+                               THROTTLE_OPS_READ,
+                               THROTTLE_OPS_WRITE);
+
+    /* bps average conflicts */
+    test_conflicts_for_one_set(true,
+                               THROTTLE_BPS_TOTAL,
+                               THROTTLE_BPS_READ,
+                               THROTTLE_BPS_WRITE);
+    /* ops average conflicts */
+    test_conflicts_for_one_set(true,
+                               THROTTLE_OPS_TOTAL,
+                               THROTTLE_OPS_READ,
+                               THROTTLE_OPS_WRITE);
+}
+/* functions to test the throttle_is_valid function */
+static void test_is_valid_for_value(int value, bool should_be_valid)
+{
+    int is_max, index;
+    for (is_max = 0; is_max < 2; is_max++) {
+        for (index = 0; index < BUCKETS_COUNT; index++) {
+            memset(&cfg, 0, sizeof(cfg));
+            set_cfg_value(is_max, index, value);
+            g_assert(throttle_is_valid(&cfg) == should_be_valid);
+        }
+    }
+}
+
+static void test_is_valid(void)
+{
+    /* negative number are invalid */
+    test_is_valid_for_value(-1, false);
+    /* zero are valids */
+    test_is_valid_for_value(0, true);
+    /* positives numers are valids */
+    test_is_valid_for_value(1, true);
+}
+
+static void test_have_timer(void)
+{
+    /* zero the structure */
+    memset(&ts, 0, sizeof(ts));
+
+    /* no timer set shoudl return false */
+    g_assert(!throttle_have_timer(&ts));
+
+    /* init the structure */
+    throttle_init(&ts, QEMU_CLOCK_VIRTUAL, read_timer_cb, write_timer_cb, &ts);
+
+    /* timer set by init should return true */
+    g_assert(throttle_have_timer(&ts));
+
+    throttle_destroy(&ts);
+}
+
+static bool do_test_accounting(bool is_ops, /* are we testing bps or ops */
+                int size,                   /* size of the operation to do */
+                double avg,                 /* io limit */
+                uint64_t op_size,           /* ideal size of an io */
+                double total_result,
+                double read_result,
+                double write_result)
+{
+    BucketType to_test[2][3] = { { THROTTLE_BPS_TOTAL,
+                                   THROTTLE_BPS_READ,
+                                   THROTTLE_BPS_WRITE, },
+                                 { THROTTLE_OPS_TOTAL,
+                                   THROTTLE_OPS_READ,
+                                   THROTTLE_OPS_WRITE, } };
+    ThrottleConfig cfg;
+    BucketType index;
+    int i;
+
+    for (i = 0; i < 3; i++) {
+        BucketType index = to_test[is_ops][i];
+        cfg.buckets[index].avg = avg;
+    }
+
+    cfg.op_size = op_size;
+
+    throttle_init(&ts, QEMU_CLOCK_VIRTUAL, read_timer_cb, write_timer_cb, &ts);
+    throttle_config(&ts, &cfg);
+
+    /* account a read */
+    throttle_account(&ts, false, size);
+    /* account a write */
+    throttle_account(&ts, true, size);
+
+    /* check total result */
+    index = to_test[is_ops][0];
+    if (!double_cmp(ts.cfg.buckets[index].level, total_result)) {
+        return false;
+    }
+
+    /* check read result */
+    index = to_test[is_ops][1];
+    if (!double_cmp(ts.cfg.buckets[index].level, read_result)) {
+        return false;
+    }
+
+    /* check write result */
+    index = to_test[is_ops][2];
+    if (!double_cmp(ts.cfg.buckets[index].level, write_result)) {
+        return false;
+    }
+
+    throttle_destroy(&ts);
+
+    return true;
+}
+
+static void test_accounting(void)
+{
+    /* tests for bps */
+
+    /* op of size 1 */
+    g_assert(do_test_accounting(false,
+                                1 * 512,
+                                150,
+                                0,
+                                1024,
+                                512,
+                                512));
+
+    /* op of size 2 */
+    g_assert(do_test_accounting(false,
+                                2 * 512,
+                                150,
+                                0,
+                                2048,
+                                1024,
+                                1024));
+
+    /* op of size 2 and orthogonal parameter change */
+    g_assert(do_test_accounting(false,
+                                2 * 512,
+                                150,
+                                17,
+                                2048,
+                                1024,
+                                1024));
+
+
+    /* tests for ops */
+
+    /* op of size 1 */
+    g_assert(do_test_accounting(true,
+                                1 * 512,
+                                150,
+                                0,
+                                2,
+                                1,
+                                1));
+
+    /* op of size 2 */
+    g_assert(do_test_accounting(true,
+                                2 *  512,
+                                150,
+                                0,
+                                2,
+                                1,
+                                1));
+
+    /* jumbo op accounting fragmentation : size 64 with op size of 13 units */
+    g_assert(do_test_accounting(true,
+                                64 * 512,
+                                150,
+                                13 * 512,
+                                (64.0 * 2) / 13,
+                                (64.0 / 13),
+                                (64.0 / 13)));
+
+    /* same with orthogonal parameters changes */
+    g_assert(do_test_accounting(true,
+                                64 * 512,
+                                300,
+                                13 * 512,
+                                (64.0 * 2) / 13,
+                                (64.0 / 13),
+                                (64.0 / 13)));
+}
+
+int main(int argc, char **argv)
+{
+    init_clocks();
+    do {} while (g_main_context_iteration(NULL, false));
+
+    /* tests in the same order as the header function declarations */
+    g_test_init(&argc, &argv, NULL);
+    g_test_add_func("/throttle/leak_bucket",        test_leak_bucket);
+    g_test_add_func("/throttle/compute_wait",       test_compute_wait);
+    g_test_add_func("/throttle/init",               test_init);
+    g_test_add_func("/throttle/destroy",            test_destroy);
+    g_test_add_func("/throttle/have_timer",         test_have_timer);
+    g_test_add_func("/throttle/config/enabled",     test_enabled);
+    g_test_add_func("/throttle/config/conflicting", test_conflicting_config);
+    g_test_add_func("/throttle/config/is_valid",    test_is_valid);
+    g_test_add_func("/throttle/config_functions",   test_config_functions);
+    g_test_add_func("/throttle/accounting",         test_accounting);
+    return g_test_run();
+}
+