Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 136 insertions, 0 deletions

diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c
new file mode 100644
index 000000000..2b8509696
--- /dev/null
+++ b/arch/s390/kernel/idle.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Idle functions for s390.
+ *
+ * Copyright IBM Corp. 2014
+ *
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/kernel_stat.h>
+#include <linux/kprobes.h>
+#include <linux/notifier.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/sched/cputime.h>
+#include <trace/events/power.h>
+#include <asm/nmi.h>
+#include <asm/smp.h>
+#include "entry.h"
+
+static DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
+
+void enabled_wait(void)
+{
+	struct s390_idle_data *idle = this_cpu_ptr(&s390_idle);
+	unsigned long long idle_time;
+	unsigned long psw_mask, flags;
+
+
+	/* Wait for external, I/O or machine check interrupt. */
+	psw_mask = PSW_KERNEL_BITS | PSW_MASK_WAIT | PSW_MASK_DAT |
+		PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
+	clear_cpu_flag(CIF_NOHZ_DELAY);
+
+	raw_local_irq_save(flags);
+	/* Call the assembler magic in entry.S */
+	psw_idle(idle, psw_mask);
+	raw_local_irq_restore(flags);
+
+	/* Account time spent with enabled wait psw loaded as idle time. */
+	raw_write_seqcount_begin(&idle->seqcount);
+	idle_time = idle->clock_idle_exit - idle->clock_idle_enter;
+	idle->clock_idle_enter = idle->clock_idle_exit = 0ULL;
+	idle->idle_time += idle_time;
+	idle->idle_count++;
+	account_idle_time(cputime_to_nsecs(idle_time));
+	raw_write_seqcount_end(&idle->seqcount);
+}
+NOKPROBE_SYMBOL(enabled_wait);
+
+static ssize_t show_idle_count(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct s390_idle_data *idle = &per_cpu(s390_idle, dev->id);
+	unsigned long long idle_count;
+	unsigned int seq;
+
+	do {
+		seq = read_seqcount_begin(&idle->seqcount);
+		idle_count = READ_ONCE(idle->idle_count);
+		if (READ_ONCE(idle->clock_idle_enter))
+			idle_count++;
+	} while (read_seqcount_retry(&idle->seqcount, seq));
+	return sprintf(buf, "%llu\n", idle_count);
+}
+DEVICE_ATTR(idle_count, 0444, show_idle_count, NULL);
+
+static ssize_t show_idle_time(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	unsigned long long now, idle_time, idle_enter, idle_exit, in_idle;
+	struct s390_idle_data *idle = &per_cpu(s390_idle, dev->id);
+	unsigned int seq;
+
+	do {
+		seq = read_seqcount_begin(&idle->seqcount);
+		idle_time = READ_ONCE(idle->idle_time);
+		idle_enter = READ_ONCE(idle->clock_idle_enter);
+		idle_exit = READ_ONCE(idle->clock_idle_exit);
+	} while (read_seqcount_retry(&idle->seqcount, seq));
+	in_idle = 0;
+	now = get_tod_clock();
+	if (idle_enter) {
+		if (idle_exit) {
+			in_idle = idle_exit - idle_enter;
+		} else if (now > idle_enter) {
+			in_idle = now - idle_enter;
+		}
+	}
+	idle_time += in_idle;
+	return sprintf(buf, "%llu\n", idle_time >> 12);
+}
+DEVICE_ATTR(idle_time_us, 0444, show_idle_time, NULL);
+
+u64 arch_cpu_idle_time(int cpu)
+{
+	struct s390_idle_data *idle = &per_cpu(s390_idle, cpu);
+	unsigned long long now, idle_enter, idle_exit, in_idle;
+	unsigned int seq;
+
+	do {
+		seq = read_seqcount_begin(&idle->seqcount);
+		idle_enter = READ_ONCE(idle->clock_idle_enter);
+		idle_exit = READ_ONCE(idle->clock_idle_exit);
+	} while (read_seqcount_retry(&idle->seqcount, seq));
+	in_idle = 0;
+	now = get_tod_clock();
+	if (idle_enter) {
+		if (idle_exit) {
+			in_idle = idle_exit - idle_enter;
+		} else if (now > idle_enter) {
+			in_idle = now - idle_enter;
+		}
+	}
+	return cputime_to_nsecs(in_idle);
+}
+
+void arch_cpu_idle_enter(void)
+{
+}
+
+void arch_cpu_idle(void)
+{
+	enabled_wait();
+	raw_local_irq_enable();
+}
+
+void arch_cpu_idle_exit(void)
+{
+}
+
+void arch_cpu_idle_dead(void)
+{
+	cpu_die();
+}