[LTP] [PATCH v2 6/6] sched/cgroup: Add cfs_bandwidth01
Richard Palethorpe
rpalethorpe@suse.com
Fri May 21 12:25:28 CEST 2021
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
---
runtest/sched | 1 +
.../kernel/sched/cfs-scheduler/.gitignore | 1 +
testcases/kernel/sched/cfs-scheduler/Makefile | 4 +-
.../sched/cfs-scheduler/cfs_bandwidth01.c | 175 ++++++++++++++++++
4 files changed, 179 insertions(+), 2 deletions(-)
create mode 100644 testcases/kernel/sched/cfs-scheduler/cfs_bandwidth01.c
diff --git a/runtest/sched b/runtest/sched
index bfc4f2711..592898723 100644
--- a/runtest/sched
+++ b/runtest/sched
@@ -6,6 +6,7 @@ pth_str03 pth_str03
time-schedule01 time-schedule
trace_sched01 trace_sched -c 1
+cfs_bandwidth01 cfs_bandwidth01 -i 5
hackbench01 hackbench 50 process 1000
hackbench02 hackbench 20 thread 1000
diff --git a/testcases/kernel/sched/cfs-scheduler/.gitignore b/testcases/kernel/sched/cfs-scheduler/.gitignore
index db2759e4f..c5dacd6ef 100644
--- a/testcases/kernel/sched/cfs-scheduler/.gitignore
+++ b/testcases/kernel/sched/cfs-scheduler/.gitignore
@@ -1 +1,2 @@
/hackbench
+cfs_bandwidth01
diff --git a/testcases/kernel/sched/cfs-scheduler/Makefile b/testcases/kernel/sched/cfs-scheduler/Makefile
index aa3bf8459..2ffe1f7f9 100644
--- a/testcases/kernel/sched/cfs-scheduler/Makefile
+++ b/testcases/kernel/sched/cfs-scheduler/Makefile
@@ -18,8 +18,8 @@
top_srcdir ?= ../../../..
-include $(top_srcdir)/include/mk/env_pre.mk
+include $(top_srcdir)/include/mk/testcases.mk
-LDLIBS += -lpthread
+hackbench: LDLIBS += -lpthread
include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/kernel/sched/cfs-scheduler/cfs_bandwidth01.c b/testcases/kernel/sched/cfs-scheduler/cfs_bandwidth01.c
new file mode 100644
index 000000000..7c988730e
--- /dev/null
+++ b/testcases/kernel/sched/cfs-scheduler/cfs_bandwidth01.c
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Copyright (c) 2021 SUSE LLC <rpalethorpe@suse.com> */
+/*\
+ *
+ * [Description]
+ *
+ * Creates a multi-level CGroup hierarchy with the cpu controller
+ * enabled. The leaf groups are populated with "busy" processes which
+ * simulate intermittent cpu load. They spin for some time then sleep
+ * then repeat.
+ *
+ * Both the trunk and leaf groups are set cpu bandwidth limits. The
+ * busy processes will intermittently exceed these limits. Causing
+ * them to be throttled. When they begin sleeping this will then cause
+ * them to be unthrottle.
+ *
+ * The test is known to reproduce an issue with an update to
+ * SLE-15-SP1 (kernel 4.12.14-197.64, bsc#1179093).
+ */
+
+#include <stdlib.h>
+
+#include "tst_test.h"
+#include "tst_cgroup.h"
+#include "tst_timer.h"
+
+static const struct tst_cgroup_group *cg_test;
+static struct tst_cgroup_group *cg_level2, *cg_level3a, *cg_level3b;
+static struct tst_cgroup_group *cg_workers[3];
+
+static void set_cpu_quota(const struct tst_cgroup_group *const cg,
+ const float quota_percent)
+{
+ const unsigned int period_us = 10000;
+ const unsigned int quota_us = (quota_percent / 100) * (float)period_us;
+
+ if (TST_CGROUP_VER(cg, "cpu") != TST_CGROUP_V1) {
+ SAFE_CGROUP_PRINTF(cg, "cpu.max",
+ "%u %u", quota_us, period_us);
+ } else {
+ SAFE_CGROUP_PRINTF(cg, "cpu.max",
+ "%u", quota_us);
+ SAFE_CGROUP_PRINTF(cg, "cpu.cfs_period_us",
+ "%u", period_us);
+ }
+
+ tst_res(TINFO, "Set '%s/cpu.max' = '%d %d'",
+ tst_cgroup_group_name(cg), quota_us, period_us);
+}
+
+static struct tst_cgroup_group *
+mk_cpu_cgroup(const struct tst_cgroup_group *const cg_parent,
+ const char *const cg_child_name,
+ const float quota_percent)
+{
+ struct tst_cgroup_group *const cg =
+ tst_cgroup_group_mk(cg_parent, cg_child_name);
+
+ set_cpu_quota(cg, quota_percent);
+
+ return cg;
+}
+
+static void busy_loop(const unsigned int sleep_ms)
+{
+ for (;;) {
+ tst_timer_start(CLOCK_MONOTONIC_RAW);
+ while (!tst_timer_expired_ms(20))
+ ;
+
+ const int ret = tst_checkpoint_wait(0, sleep_ms);
+
+ if (!ret)
+ exit(0);
+
+ if (errno != ETIMEDOUT)
+ tst_brk(TBROK | TERRNO, "tst_checkpoint_wait");
+ }
+}
+
+static void fork_busy_procs_in_cgroup(const struct tst_cgroup_group *const cg)
+{
+ const unsigned int sleeps_ms[] = {3000, 1000, 10};
+ const pid_t worker_pid = SAFE_FORK();
+ size_t i;
+
+ if (worker_pid)
+ return;
+
+ for (i = 0; i < ARRAY_SIZE(sleeps_ms); i++) {
+ const pid_t busy_pid = SAFE_FORK();
+
+ if (!busy_pid)
+ busy_loop(sleeps_ms[i]);
+
+ SAFE_CGROUP_PRINTF(cg, "cgroup.procs", "%d", busy_pid);
+ }
+
+ tst_reap_children();
+
+ exit(0);
+}
+
+static void do_test(void)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(cg_workers); i++)
+ fork_busy_procs_in_cgroup(cg_workers[i]);
+
+ tst_res(TPASS, "Scheduled bandwidth constrained workers");
+
+ sleep(1);
+
+ set_cpu_quota(cg_level2, 50);
+
+ sleep(2);
+
+ TST_CHECKPOINT_WAKE2(0, 3 * 3);
+ tst_reap_children();
+
+ tst_res(TPASS, "Workers exited");
+}
+
+static void setup(void)
+{
+ tst_cgroup_require("cpu", NULL);
+
+ cg_test = tst_cgroup_get_test_group();
+
+ cg_level2 = tst_cgroup_group_mk(cg_test, "level2");
+
+ cg_level3a = tst_cgroup_group_mk(cg_level2, "level3a");
+ cg_workers[0] = mk_cpu_cgroup(cg_level3a, "worker1", 30);
+ cg_workers[1] = mk_cpu_cgroup(cg_level3a, "worker2", 20);
+
+ cg_level3b = tst_cgroup_group_mk(cg_level2, "level3b");
+ cg_workers[2] = mk_cpu_cgroup(cg_level3b, "worker3", 30);
+}
+
+static void cleanup(void)
+{
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(cg_workers); i++) {
+ if (cg_workers[i])
+ cg_workers[i] = tst_cgroup_group_rm(cg_workers[i]);
+ }
+
+ if (cg_level3a)
+ cg_level3a = tst_cgroup_group_rm(cg_level3a);
+ if (cg_level3b)
+ cg_level3b = tst_cgroup_group_rm(cg_level3b);
+ if (cg_level2)
+ cg_level2 = tst_cgroup_group_rm(cg_level2);
+
+ tst_cgroup_cleanup();
+}
+
+static struct tst_test test = {
+ .test_all = do_test,
+ .setup = setup,
+ .cleanup = cleanup,
+ .forks_child = 1,
+ .needs_checkpoints = 1,
+ .taint_check = TST_TAINT_W | TST_TAINT_D,
+ .tags = (const struct tst_tag[]) {
+ {"linux-git", "39f23ce07b93"},
+ {"linux-git", "b34cb07dde7c"},
+ {"linux-git", "fe61468b2cbc"},
+ {"linux-git", "5ab297bab984"},
+ {"linux-git", "6d4d22468dae"},
+ { }
+ }
+};
--
2.31.1
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