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-rw-r--r--src/vppinfra/test_timing_wheel.c389
1 files changed, 389 insertions, 0 deletions
diff --git a/src/vppinfra/test_timing_wheel.c b/src/vppinfra/test_timing_wheel.c
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+++ b/src/vppinfra/test_timing_wheel.c
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+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <vppinfra/bitmap.h>
+#include <vppinfra/error.h>
+#include <vppinfra/format.h>
+#include <vppinfra/pool.h>
+#include <vppinfra/random.h>
+#include <vppinfra/time.h>
+#include <vppinfra/timing_wheel.h>
+#include <vppinfra/zvec.h>
+
+#include <vppinfra/math.h>
+
+#if __GNUC__ < 4
+#define SQRT(a) a
+#else
+#define SQRT(a) sqrt(a)
+#endif
+
+typedef struct
+{
+ uword n_iter;
+
+ u32 n_events;
+ u32 seed;
+ u32 verbose;
+
+ /* Time is "synthetic" e.g. not taken from CPU timer. */
+ u32 synthetic_time;
+
+ clib_time_t time;
+ timing_wheel_t timing_wheel;
+
+ u64 *events;
+
+ f64 max_time;
+ f64 wait_time;
+
+ f64 total_iterate_time;
+ f64 time_iterate_start;
+
+ f64 time_per_status_update;
+ f64 time_next_status_update;
+} test_timing_wheel_main_t;
+
+typedef struct
+{
+ f64 dt;
+ f64 fraction;
+ u64 count;
+} test_timing_wheel_tmp_t;
+
+static void
+set_event (test_timing_wheel_main_t * tm, uword i)
+{
+ timing_wheel_t *w = &tm->timing_wheel;
+ u64 cpu_time;
+
+ cpu_time = w->current_time_index << w->log2_clocks_per_bin;
+ if (tm->synthetic_time)
+ cpu_time += random_u32 (&tm->seed) % tm->n_iter;
+ else
+ cpu_time +=
+ random_f64 (&tm->seed) * tm->max_time * tm->time.clocks_per_second;
+
+ timing_wheel_insert (w, cpu_time, i);
+ timing_wheel_validate (w);
+ tm->events[i] = cpu_time;
+}
+
+static int
+test_timing_wheel_tmp_cmp (void *a1, void *a2)
+{
+ test_timing_wheel_tmp_t *f1 = a1;
+ test_timing_wheel_tmp_t *f2 = a2;
+
+ return f1->dt < f2->dt ? -1 : (f1->dt > f2->dt ? +1 : 0);
+}
+
+clib_error_t *
+test_timing_wheel_main (unformat_input_t * input)
+{
+ clib_error_t *error = 0;
+ test_timing_wheel_main_t _tm, *tm = &_tm;
+ timing_wheel_t *w = &tm->timing_wheel;
+ uword iter, i;
+
+ memset (tm, 0, sizeof (tm[0]));
+ tm->n_iter = 10;
+ tm->time_per_status_update = 0;
+ tm->n_events = 100;
+ tm->seed = 1;
+ tm->synthetic_time = 1;
+ tm->max_time = 1;
+ tm->wait_time = 1e-3;
+
+ w->validate = 0;
+ w->n_wheel_elt_time_bits = 32;
+
+ while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+ {
+ if (unformat (input, "iter %wd", &tm->n_iter))
+ ;
+ else if (unformat (input, "events %d", &tm->n_events))
+ ;
+ else
+ if (unformat (input, "elt-time-bits %d", &w->n_wheel_elt_time_bits))
+ ;
+ else if (unformat (input, "seed %d", &tm->seed))
+ ;
+ else if (unformat (input, "verbose"))
+ tm->verbose = 1;
+ else if (unformat (input, "validate"))
+ w->validate = 1;
+
+ else if (unformat (input, "real-time"))
+ tm->synthetic_time = 0;
+ else if (unformat (input, "synthetic-time"))
+ tm->synthetic_time = 1;
+ else if (unformat (input, "max-time %f", &tm->max_time))
+ ;
+ else if (unformat (input, "wait-time %f", &tm->wait_time))
+ ;
+ else if (unformat (input, "iter-time %f", &tm->total_iterate_time))
+ ;
+ else if (unformat (input, "print %f", &tm->time_per_status_update))
+ ;
+
+ else
+ {
+ error = clib_error_create ("unknown input `%U'\n",
+ format_unformat_error, input);
+ goto done;
+ }
+ }
+
+ if (!tm->seed)
+ tm->seed = random_default_seed ();
+
+ clib_time_init (&tm->time);
+
+ if (tm->synthetic_time)
+ {
+ w->min_sched_time = tm->time.seconds_per_clock;
+ w->max_sched_time = w->min_sched_time * 256;
+ timing_wheel_init (w, 0, tm->time.clocks_per_second);
+ }
+ else
+ {
+ timing_wheel_init (w, clib_cpu_time_now (), tm->time.clocks_per_second);
+ }
+
+ clib_warning ("iter %wd, events %d, seed %u, %U",
+ tm->n_iter, tm->n_events, tm->seed,
+ format_timing_wheel, &tm->timing_wheel, /* verbose */ 0);
+
+ /* Make some events. */
+ vec_resize (tm->events, tm->n_events);
+ for (i = 0; i < vec_len (tm->events); i++)
+ set_event (tm, i);
+
+ {
+ u32 *expired = 0;
+ f64 ave_error = 0;
+ f64 rms_error = 0;
+ f64 max_error = 0, min_error = 1e30;
+ u32 *error_hist = 0;
+ uword n_expired = 0;
+ uword *expired_bitmap[2] = { 0 };
+ uword n_events_in_wheel = vec_len (tm->events);
+
+ vec_resize (expired, 32);
+ vec_resize (error_hist, 1024);
+
+ tm->time_iterate_start = clib_time_now (&tm->time);
+ tm->time_next_status_update =
+ tm->time_iterate_start + tm->time_per_status_update;
+
+ if (tm->total_iterate_time != 0)
+ tm->n_iter = ~0;
+
+ for (iter = 0; iter < tm->n_iter || n_events_in_wheel > 0; iter++)
+ {
+ u64 cpu_time, min_next_time[2];
+
+ if (tm->synthetic_time)
+ cpu_time = iter << w->log2_clocks_per_bin;
+ else
+ cpu_time = clib_cpu_time_now ();
+
+ _vec_len (expired) = 0;
+ expired =
+ timing_wheel_advance (w, cpu_time, expired, &min_next_time[0]);
+ timing_wheel_validate (w);
+
+ /* Update bitmap of expired events. */
+ if (w->validate)
+ {
+ for (i = 0; i < vec_len (tm->events); i++)
+ {
+ uword is_expired;
+
+ is_expired =
+ (cpu_time >> w->log2_clocks_per_bin) >=
+ (tm->events[i] >> w->log2_clocks_per_bin);
+ expired_bitmap[0] =
+ clib_bitmap_set (expired_bitmap[0], i, is_expired);
+
+ /* Validate min next time. */
+ if (is_expired)
+ ASSERT (min_next_time[0] > tm->events[i]);
+ else
+ ASSERT (min_next_time[0] <= tm->events[i]);
+ }
+ }
+
+ n_expired += vec_len (expired);
+ for (i = 0; i < vec_len (expired); i++)
+ {
+ word j, idt;
+ i64 dt_cpu;
+ f64 fdt_cpu;
+
+ j = expired[i];
+ expired_bitmap[1] = clib_bitmap_ori (expired_bitmap[1], j);
+
+ dt_cpu = cpu_time - tm->events[j];
+
+ /* Event must be scheduled in correct bin. */
+ if (tm->synthetic_time)
+ ASSERT (dt_cpu >= 0 && dt_cpu <= (1 << w->log2_clocks_per_bin));
+
+ fdt_cpu = dt_cpu * tm->time.seconds_per_clock;
+
+ ave_error += fdt_cpu;
+ rms_error += fdt_cpu * fdt_cpu;
+
+ if (fdt_cpu > max_error)
+ max_error = fdt_cpu;
+ if (fdt_cpu < min_error)
+ min_error = fdt_cpu;
+
+ idt =
+ (cpu_time >> w->log2_clocks_per_bin) -
+ (tm->events[j] >> w->log2_clocks_per_bin);
+ idt = zvec_signed_to_unsigned (idt);
+ vec_validate (error_hist, idt);
+ error_hist[idt] += 1;
+ }
+
+ if (w->validate)
+ for (i = 0; i < vec_len (tm->events); i++)
+ {
+ int is_expired = clib_bitmap_get (expired_bitmap[0], i);
+ int is_expired_w = clib_bitmap_get (expired_bitmap[1], i);
+ ASSERT (is_expired == is_expired_w);
+ }
+
+ min_next_time[1] = ~0;
+ for (i = 0; i < vec_len (tm->events); i++)
+ {
+ if (!clib_bitmap_get (expired_bitmap[1], i))
+ min_next_time[1] = clib_min (min_next_time[1], tm->events[i]);
+ }
+ if (min_next_time[0] != min_next_time[1])
+ clib_error ("min next time wrong 0x%Lx != 0x%Lx", min_next_time[0],
+ min_next_time[1]);
+
+ if (tm->time_per_status_update != 0
+ && clib_time_now (&tm->time) >= tm->time_next_status_update)
+ {
+ f64 ave = 0, rms = 0;
+
+ tm->time_next_status_update += tm->time_per_status_update;
+ if (n_expired > 0)
+ {
+ ave = ave_error / n_expired;
+ rms = SQRT (rms_error / n_expired - ave * ave);
+ }
+
+ clib_warning
+ ("%12wd iter done %10wd expired; ave. error %.4e +- %.4e, range %.4e %.4e",
+ iter, n_expired, ave, rms, min_error, max_error);
+ }
+
+ if (tm->total_iterate_time != 0
+ && (clib_time_now (&tm->time) - tm->time_iterate_start
+ >= tm->total_iterate_time))
+ tm->n_iter = iter;
+
+ /* Add new events to wheel to replace expired ones. */
+ n_events_in_wheel -= vec_len (expired);
+ if (iter < tm->n_iter)
+ {
+ for (i = 0; i < vec_len (expired); i++)
+ {
+ uword j = expired[i];
+ set_event (tm, j);
+ expired_bitmap[1] =
+ clib_bitmap_andnoti (expired_bitmap[1], j);
+ }
+ n_events_in_wheel += vec_len (expired);
+ }
+ }
+
+ ave_error /= n_expired;
+ rms_error = SQRT (rms_error / n_expired - ave_error * ave_error);
+
+ clib_warning
+ ("%wd iter done %wd expired; ave. error %.4e +- %.4e, range %.4e %.4e",
+ 1 + iter, n_expired, ave_error, rms_error, min_error, max_error);
+
+ {
+ test_timing_wheel_tmp_t *fs, *f;
+ f64 total_fraction;
+
+ fs = 0;
+ for (i = 0; i < vec_len (error_hist); i++)
+ {
+ if (error_hist[i] == 0)
+ continue;
+ vec_add2 (fs, f, 1);
+ f->dt =
+ (((i64) zvec_unsigned_to_signed (i) << w->log2_clocks_per_bin) *
+ tm->time.seconds_per_clock);
+ f->fraction = (f64) error_hist[i] / (f64) n_expired;
+ f->count = error_hist[i];
+ }
+
+ vec_sort_with_function (fs, test_timing_wheel_tmp_cmp);
+
+ total_fraction = 0;
+ vec_foreach (f, fs)
+ {
+ total_fraction += f->fraction;
+ if (f == fs)
+ fformat (stdout, "%=12s %=16s %=16s %s\n", "Error max", "Fraction",
+ "Total", "Count");
+ fformat (stdout, "%12.4e %16.4f%% %16.4f%% %Ld\n", f->dt,
+ f->fraction * 100, total_fraction * 100, f->count);
+ }
+ }
+
+ clib_warning ("%U", format_timing_wheel, w, /* verbose */ 1);
+ }
+
+done:
+ return error;
+}
+
+#ifdef CLIB_UNIX
+int
+main (int argc, char *argv[])
+{
+ unformat_input_t i;
+ clib_error_t *error;
+
+ unformat_init_command_line (&i, argv);
+ error = test_timing_wheel_main (&i);
+ unformat_free (&i);
+ if (error)
+ {
+ clib_error_report (error);
+ return 1;
+ }
+ else
+ return 0;
+}
+#endif /* CLIB_UNIX */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */