llc: Add CoDel AQM implementation
This commit adds an implementation of the CoDel algorithm based on
the reference pseudocode presented in
http://queue.acm.org/appendices/codel.html. Instead of abstracting
the queue itself, the implementation provides a time stamp based
automaton which is invoked after a package has been dequeued.
Note that the modifications of the algorithm shown in
https://tools.ietf.org/html/draft-ietf-aqm-codel-01 are not yet
applied.
Sponsored-by: On-Waves ehf
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 5d7aab0..413599b 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -1,7 +1,7 @@
AM_CPPFLAGS = $(STD_DEFINES_AND_INCLUDES) $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGB_CFLAGS) $(LIBOSMOGSM_CFLAGS) -I$(top_srcdir)/src/
AM_LDFLAGS = -lrt
-check_PROGRAMS = rlcmac/RLCMACTest alloc/AllocTest tbf/TbfTest types/TypesTest ms/MsTest llist/LListTest llc/LlcTest
+check_PROGRAMS = rlcmac/RLCMACTest alloc/AllocTest tbf/TbfTest types/TypesTest ms/MsTest llist/LListTest llc/LlcTest codel/codel_test
noinst_PROGRAMS = emu/pcu_emu
rlcmac_RLCMACTest_SOURCES = rlcmac/RLCMACTest.cpp
@@ -71,6 +71,12 @@
$(LIBOSMOCORE_LIBS) \
$(COMMON_LA)
+codel_codel_test_SOURCES = codel/codel_test.c
+codel_codel_test_LDADD = \
+ $(top_builddir)/src/libgprs.la \
+ $(LIBOSMOCORE_LIBS) \
+ $(COMMON_LA)
+
# The `:;' works around a Bash 3.2 bug when the output is not writeable.
$(srcdir)/package.m4: $(top_srcdir)/configure.ac
:;{ \
@@ -97,7 +103,8 @@
types/TypesTest.ok types/TypesTest.err \
ms/MsTest.ok ms/MsTest.err \
llc/LlcTest.ok llc/LlcTest.err \
- llist/LListTest.ok llist/LListTest.err
+ llist/LListTest.ok llist/LListTest.err \
+ codel/codel_test.ok
DISTCLEANFILES = atconfig
diff --git a/tests/codel/codel_test.c b/tests/codel/codel_test.c
new file mode 100644
index 0000000..91bad13
--- /dev/null
+++ b/tests/codel/codel_test.c
@@ -0,0 +1,147 @@
+/* Test routines for the CoDel implementation
+ *
+ * (C) 2015 by sysmocom s.f.m.c. GmbH
+ * Author: Jacob Erlbeck <jerlbeck@sysmocom.de>
+ */
+
+#undef _GNU_SOURCE
+#define _GNU_SOURCE
+
+#if 0
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/prim.h>
+#endif
+#include <osmocom/core/application.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/logging.h>
+
+#include "gprs_codel.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+static int do_codel_control(struct gprs_codel *state, const struct timeval *recv,
+ struct timeval *now, const struct timeval *delta_now, int count)
+{
+ int drop;
+
+ drop = gprs_codel_control(state, recv, now, -1);
+ if (drop) {
+ printf("Dropping packet %d, "
+ "recv = %d.%03d, now = %d.%03d, "
+ "codel.count = %d\n",
+ count,
+ (int)recv->tv_sec, (int)recv->tv_usec/1000,
+ (int)now->tv_sec, (int)now->tv_usec/1000,
+ state->count);
+ } else {
+ timeradd(now, delta_now, now);
+ }
+
+ return drop == 0 ? 0 : 1;
+}
+
+static void test_codel(void)
+{
+ struct gprs_codel codel;
+ struct timeval now;
+ struct timeval recv;
+ const struct timeval delta_now = {0, 10000};
+ const struct timeval init_delta_recv = {0, 5000};
+ struct timeval delta_recv;
+ unsigned count;
+ unsigned sum = 0;
+ unsigned dropped = 0;
+ int drop;
+
+ printf("----- %s START\n", __func__);
+ gprs_codel_init(&codel);
+ gprs_codel_set_interval(&codel, 100);
+
+ timerclear(&now);
+ timerclear(&recv);
+ delta_recv = init_delta_recv;
+
+ for (count = 0; count < 20; count++, sum++) {
+ drop = do_codel_control(&codel, &recv, &now, &delta_now, sum);
+ timeradd(&recv, &delta_recv, &recv);
+ dropped += drop;
+ }
+
+ printf("Dropped %d packets\n", dropped);
+ OSMO_ASSERT(dropped == 0);
+ OSMO_ASSERT(!codel.dropping);
+
+ for (count = 0; count < 20; count++, sum++) {
+ drop = do_codel_control(&codel, &recv, &now, &delta_now, sum);
+ timeradd(&recv, &delta_recv, &recv);
+ dropped += drop;
+ }
+
+ OSMO_ASSERT(dropped == 2);
+ OSMO_ASSERT(codel.dropping);
+
+ /* slow down recv rate */
+ delta_recv.tv_usec = delta_now.tv_usec;
+
+ for (count = 0; count < 75; count++, sum++) {
+ drop = do_codel_control(&codel, &recv, &now, &delta_now, sum);
+ timeradd(&recv, &delta_recv, &recv);
+ dropped += drop;
+ }
+
+ OSMO_ASSERT(dropped == 20);
+ OSMO_ASSERT(codel.dropping);
+
+ for (count = 0; count < 50; count++, sum++) {
+ drop = do_codel_control(&codel, &recv, &now, &delta_now, sum);
+ timeradd(&recv, &delta_recv, &recv);
+ dropped += drop;
+ }
+
+ OSMO_ASSERT(dropped == 20);
+ OSMO_ASSERT(!codel.dropping);
+ OSMO_ASSERT(codel.count >= 20);
+
+ /* go back to old data rate */
+ delta_recv = init_delta_recv;
+
+ for (count = 0; count < 20; count++, sum++) {
+ drop = do_codel_control(&codel, &recv, &now, &delta_now, sum);
+ timeradd(&recv, &delta_recv, &recv);
+ dropped += drop;
+ }
+
+ OSMO_ASSERT(dropped == 20);
+ OSMO_ASSERT(!codel.dropping);
+
+ for (count = 0; count < 20; count++, sum++) {
+ drop = do_codel_control(&codel, &recv, &now, &delta_now, sum);
+ timeradd(&recv, &delta_recv, &recv);
+ dropped += drop;
+ }
+
+ OSMO_ASSERT(dropped == 22);
+ OSMO_ASSERT(codel.count >= 2);
+
+ printf("Dropped %d packets\n", dropped);
+
+ printf("----- %s END\n", __func__);
+}
+
+static struct log_info info = {};
+
+int main(int argc, char **argv)
+{
+ osmo_init_logging(&info);
+ log_set_use_color(osmo_stderr_target, 0);
+ log_set_print_filename(osmo_stderr_target, 0);
+ log_set_log_level(osmo_stderr_target, LOGL_INFO);
+
+ printf("===== CoDel test START\n");
+ test_codel();
+ printf("===== CoDel test END\n\n");
+
+ exit(EXIT_SUCCESS);
+}
diff --git a/tests/codel/codel_test.ok b/tests/codel/codel_test.ok
new file mode 100644
index 0000000..ec0696e
--- /dev/null
+++ b/tests/codel/codel_test.ok
@@ -0,0 +1,29 @@
+===== CoDel test START
+----- test_codel START
+Dropped 0 packets
+Dropping packet 21, recv = 0.105, now = 0.210, codel.count = 1
+Dropping packet 32, recv = 0.160, now = 0.310, codel.count = 2
+Dropping packet 41, recv = 0.210, now = 0.390, codel.count = 3
+Dropping packet 47, recv = 0.270, now = 0.440, codel.count = 4
+Dropping packet 53, recv = 0.330, now = 0.490, codel.count = 5
+Dropping packet 59, recv = 0.390, now = 0.540, codel.count = 6
+Dropping packet 64, recv = 0.440, now = 0.580, codel.count = 7
+Dropping packet 69, recv = 0.490, now = 0.620, codel.count = 8
+Dropping packet 73, recv = 0.530, now = 0.650, codel.count = 9
+Dropping packet 77, recv = 0.570, now = 0.680, codel.count = 10
+Dropping packet 81, recv = 0.610, now = 0.710, codel.count = 11
+Dropping packet 86, recv = 0.660, now = 0.750, codel.count = 12
+Dropping packet 89, recv = 0.690, now = 0.770, codel.count = 13
+Dropping packet 93, recv = 0.730, now = 0.800, codel.count = 14
+Dropping packet 97, recv = 0.770, now = 0.830, codel.count = 15
+Dropping packet 100, recv = 0.800, now = 0.850, codel.count = 16
+Dropping packet 104, recv = 0.840, now = 0.880, codel.count = 17
+Dropping packet 107, recv = 0.870, now = 0.900, codel.count = 18
+Dropping packet 111, recv = 0.910, now = 0.930, codel.count = 19
+Dropping packet 114, recv = 0.940, now = 0.950, codel.count = 20
+Dropping packet 186, recv = 1.555, now = 1.660, codel.count = 1
+Dropping packet 197, recv = 1.610, now = 1.760, codel.count = 2
+Dropped 22 packets
+----- test_codel END
+===== CoDel test END
+
diff --git a/tests/testsuite.at b/tests/testsuite.at
index d7a85e5..71179d1 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -50,3 +50,9 @@
cat $abs_srcdir/llist/LListTest.err > experr
AT_CHECK([$OSMO_QEMU $abs_top_builddir/tests/llist/LListTest], [0], [expout], [experr])
AT_CLEANUP
+
+AT_SETUP([codel])
+AT_KEYWORDS([codel])
+cat $abs_srcdir/codel/codel_test.ok > expout
+AT_CHECK([$OSMO_QEMU $abs_top_builddir/tests/codel/codel_test], [0], [expout], [ignore])
+AT_CLEANUP