gpu: nvgpu: add periodic timer API

move fecs_trace polling from kthread to timer API.

Jira GVSCI-10883

Signed-off-by: Richard Zhao <rizhao@nvidia.com>
Change-Id: I224754b7205f1d0eefdc19a73a98f42e4d3e9d0e
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2700601
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-cert <svc-mobile-cert@nvidia.com>
Reviewed-by: Shashank Singh <shashsingh@nvidia.com>
Reviewed-by: Aparna Das <aparnad@nvidia.com>
GVS: Gerrit_Virtual_Submit

drivers/gpu/nvgpu/os/linux/periodic_timer.c

@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2022, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <nvgpu/bug.h>
+#include <nvgpu/periodic_timer.h>
+#include <linux/async.h>
+
+static void async_func(void *data, async_cookie_t cookie)
+{
+	struct nvgpu_periodic_timer *timer = data;
+
+	timer->fn(timer->arg);
+	raw_spin_lock(&timer->lock);
+	if (timer->enabled) {
+		hrtimer_start(&timer->timer, timer->interval, HRTIMER_MODE_REL);
+	}
+	raw_spin_unlock(&timer->lock);
+}
+
+static enum hrtimer_restart timer_callback(struct hrtimer *os_timer)
+{
+	struct nvgpu_periodic_timer *timer =
+			container_of(os_timer, struct nvgpu_periodic_timer, timer);
+
+	timer->async_cookie = async_schedule(async_func, timer);
+	return HRTIMER_NORESTART;
+}
+
+int nvgpu_periodic_timer_init(struct nvgpu_periodic_timer *timer,
+			void (*fn)(void *arg), void *arg)
+{
+	hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	timer->timer.function = timer_callback;
+	timer->fn = fn;
+	timer->arg = arg;
+	timer->interval = ktime_set(0, 0);
+	timer->async_cookie = 0;
+	timer->enabled = false;
+	raw_spin_lock_init(&timer->lock);
+	return 0;
+}
+
+int nvgpu_periodic_timer_start(struct nvgpu_periodic_timer *timer,
+				u64 interval_ns)
+{
+	raw_spin_lock(&timer->lock);
+	timer->interval = ns_to_ktime(interval_ns);
+	timer->enabled = true;
+	timer->async_cookie = 0;
+	hrtimer_start(&timer->timer, timer->interval, HRTIMER_MODE_REL);
+	raw_spin_unlock(&timer->lock);
+
+	return 0;
+}
+
+int nvgpu_periodic_timer_stop(struct nvgpu_periodic_timer *timer)
+{
+	raw_spin_lock(&timer->lock);
+	if (!timer->enabled) {
+		raw_spin_unlock(&timer->lock);
+		return 0;
+	}
+	timer->enabled = false;
+	raw_spin_unlock(&timer->lock);
+	hrtimer_cancel(&timer->timer);
+	if (timer->async_cookie != 0) {
+		async_synchronize_cookie(timer->async_cookie + 1);
+	}
+	return 0;
+}
+
+int nvgpu_periodic_timer_destroy(struct nvgpu_periodic_timer *timer)
+{
+	return nvgpu_periodic_timer_stop(timer);
+}