[PATCH tip/core/rcu 07/28] rcuscale: Add RCU Tasks Trace

paulmck
2020-11-05T23:48:41Z

This commit adds the ability to test performance and scalability of RCU
Tasks Trace updaters.

Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/rcuscale.c | 32 +++++++++++++++++++++-
.../selftests/rcutorture/configs/rcuscale/CFcommon | 3 ++
.../selftests/rcutorture/configs/rcuscale/TRACE01 | 15 ++++++++++
.../rcutorture/configs/rcuscale/TRACE01.boot | 1 +
4 files changed, 50 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01
create mode 100644 tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01.boot

diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index 2819b95..c42f240 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -38,6 +38,7 @@
#include <asm/byteorder.h>
#include <linux/torture.h>
#include <linux/vmalloc.h>
+#include <linux/rcupdate_trace.h>

#include "rcu.h"

@@ -294,6 +295,35 @@ static struct rcu_scale_ops tasks_ops = {
.name = "tasks"
};

+/*
+ * Definitions for RCU-tasks-trace scalability testing.
+ */
+
+static int tasks_trace_scale_read_lock(void)
+{
+ rcu_read_lock_trace();
+ return 0;
+}
+
+static void tasks_trace_scale_read_unlock(int idx)
+{
+ rcu_read_unlock_trace();
+}
+
+static struct rcu_scale_ops tasks_tracing_ops = {
+ .ptype = RCU_TASKS_FLAVOR,
+ .init = rcu_sync_scale_init,
+ .readlock = tasks_trace_scale_read_lock,
+ .readunlock = tasks_trace_scale_read_unlock,
+ .get_gp_seq = rcu_no_completed,
+ .gp_diff = rcu_seq_diff,
+ .async = call_rcu_tasks_trace,
+ .gp_barrier = rcu_barrier_tasks_trace,
+ .sync = synchronize_rcu_tasks_trace,
+ .exp_sync = synchronize_rcu_tasks_trace,
+ .name = "tasks-tracing"
+};
+
static unsigned long rcuscale_seq_diff(unsigned long new, unsigned long old)
{
if (!cur_ops->gp_diff)
@@ -754,7 +784,7 @@ rcu_scale_init(void)
long i;
int firsterr = 0;
static struct rcu_scale_ops *scale_ops[] = {
- &rcu_ops, &srcu_ops, &srcud_ops, &tasks_ops,
+ &rcu_ops, &srcu_ops, &srcud_ops, &tasks_ops, &tasks_tracing_ops
};

if (!torture_init_begin(scale_type, verbose))
diff --git a/tools/testing/selftests/rcutorture/configs/rcuscale/CFcommon b/tools/testing/selftests/rcutorture/configs/rcuscale/CFcommon
index 87caa0e..90942bb 100644
--- a/tools/testing/selftests/rcutorture/configs/rcuscale/CFcommon
+++ b/tools/testing/selftests/rcutorture/configs/rcuscale/CFcommon
@@ -1,2 +1,5 @@
CONFIG_RCU_SCALE_TEST=y
CONFIG_PRINTK_TIME=y
+CONFIG_TASKS_RCU_GENERIC=y
+CONFIG_TASKS_RCU=y
+CONFIG_TASKS_TRACE_RCU=y
diff --git a/tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01 b/tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01
new file mode 100644
index 0000000..e6baa2f
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01
@@ -0,0 +1,15 @@
+CONFIG_SMP=y
+CONFIG_PREEMPT_NONE=y
+CONFIG_PREEMPT_VOLUNTARY=n
+CONFIG_PREEMPT=n
+CONFIG_HZ_PERIODIC=n
+CONFIG_NO_HZ_IDLE=y
+CONFIG_NO_HZ_FULL=n
+CONFIG_RCU_FAST_NO_HZ=n
+CONFIG_RCU_NOCB_CPU=n
+CONFIG_DEBUG_LOCK_ALLOC=n
+CONFIG_PROVE_LOCKING=n
+CONFIG_RCU_BOOST=n
+CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
+CONFIG_RCU_EXPERT=y
+CONFIG_RCU_TRACE=y
diff --git a/tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01.boot b/tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01.boot
new file mode 100644
index 0000000..af0aff1
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/rcuscale/TRACE01.boot
@@ -0,0 +1 @@
+rcuscale.scale_type=tasks-tracing
--
2.9.5