event: Scheduler plugin for using governors

Signed-off-by: Maciej Szwed <maciej.szwed@intel.com>
Change-Id: I2edc6e31eb91fff9e1b7f0a3a05cf7cd5dc79a58
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/4163
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

lib/event/Makefile

@@ -44,7 +44,7 @@ C_SRCS = app.c reactor.c rpc.c subsystem.c json_config.c log_rpc.c \
 	 app_rpc.c subsystem_rpc.c scheduler_static.c
 
 ifeq ($(OS),Linux)
-C_SRCS += dpdk_governor.c
+C_SRCS += gscheduler.c dpdk_governor.c
 endif
 
 SPDK_MAP_FILE = $(abspath $(CURDIR)/spdk_event.map)

lib/event/gscheduler.c

@@ -0,0 +1,167 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (c) Intel Corporation.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "spdk/stdinc.h"
+#include "spdk/likely.h"
+
+#include "spdk_internal/event.h"
+#include "spdk_internal/thread.h"
+
+#include "spdk/log.h"
+#include "spdk/env.h"
+
+static int
+init(struct spdk_governor *governor)
+{
+	return _spdk_governor_set("dpdk_governor");
+}
+
+static int
+deinit(struct spdk_governor *governor)
+{
+	uint32_t i;
+	int rc = 0;
+
+	SPDK_ENV_FOREACH_CORE(i) {
+		if (governor->deinit_core) {
+			rc = governor->deinit_core(i);
+			if (rc != 0) {
+				return rc;
+			}
+		}
+	}
+
+	if (governor->deinit) {
+		rc = governor->deinit();
+	}
+
+	return rc;
+}
+
+static void
+balance(struct spdk_scheduler_core_info *cores, int core_count, struct spdk_governor *governor)
+{
+	struct spdk_scheduler_core_info *core;
+	struct spdk_lw_thread *thread;
+	struct spdk_governor_capabilities capabilities;
+	uint32_t i, j;
+	int rc;
+	bool turbo_available = false;
+
+	/* Gather active/idle statistics */
+	SPDK_ENV_FOREACH_CORE(i) {
+		core = &cores[i];
+
+		for (j = 0; j < core->threads_count; j++) {
+			thread = core->threads[j];
+
+			/* do not change thread lcore */
+			thread->new_lcore = thread->lcore;
+		}
+
+		rc = governor->get_core_capabilities(core->lcore, &capabilities);
+		if (rc < 0) {
+			SPDK_ERRLOG("failed to get capabilities for core: %u\n", core->lcore);
+			return;
+		}
+
+		turbo_available = (capabilities.turbo_available && capabilities.turbo_set) ? true : false;
+
+		if (core->core_busy_tsc < (core->core_idle_tsc / 1000)) {
+			rc = governor->set_core_freq_min(core->lcore);
+			if (rc < 0) {
+				SPDK_ERRLOG("setting to minimal frequency for core %u failed\n", core->lcore);
+			}
+
+			if (turbo_available) {
+				rc = governor->disable_core_turbo(core->lcore);
+				if (rc < 0) {
+					SPDK_ERRLOG("setting to minimal frequency for core %u failed\n", core->lcore);
+				}
+			}
+
+			SPDK_DEBUGLOG(reactor, "setting to minimal frequency for core: %u\n", core->lcore);
+		} else if (core->core_idle_tsc > core->core_busy_tsc) {
+			rc = governor->core_freq_down(core->lcore);
+			if (rc < 0) {
+				SPDK_ERRLOG("lowering frequency for core %u failed\n", core->lcore);
+			}
+
+			if (turbo_available) {
+				rc = governor->disable_core_turbo(core->lcore);
+				if (rc < 0) {
+					SPDK_ERRLOG("disabling turbo for core %u failed\n", core->lcore);
+				}
+			}
+
+			SPDK_DEBUGLOG(reactor, "lowering frequency for core: %u\n", core->lcore);
+		} else if (core->core_idle_tsc < (core->core_busy_tsc / 1000)) {
+			rc = governor->set_core_freq_max(core->lcore);
+			if (rc < 0) {
+				SPDK_ERRLOG("setting to maximal frequency for core %u failed\n", core->lcore);
+			}
+
+			if (turbo_available) {
+				rc = governor->enable_core_turbo(core->lcore);
+				if (rc < 0) {
+					SPDK_ERRLOG("enabling turbo for core %u failed\n", core->lcore);
+				}
+			}
+
+			SPDK_DEBUGLOG(reactor, "setting to maximum frequency for core: %u\n", core->lcore);
+		} else {
+			rc = governor->core_freq_up(core->lcore);
+			if (rc < 0) {
+				SPDK_ERRLOG("increasing frequency for core %u failed\n", core->lcore);
+			}
+
+			if (turbo_available) {
+				rc = governor->disable_core_turbo(core->lcore);
+				if (rc < 0) {
+					SPDK_ERRLOG("disabling turbo for core %u failed\n", core->lcore);
+				}
+			}
+
+			SPDK_DEBUGLOG(reactor, "increasing frequency for core: %u\n", core->lcore);
+		}
+	}
+}
+
+static struct spdk_scheduler gscheduler = {
+	.name = "gscheduler",
+	.init = init,
+	.deinit = deinit,
+	.balance = balance,
+};
+
+SPDK_SCHEDULER_REGISTER(&gscheduler);