mirror of
https://github.com/torvalds/linux.git
synced 2024-12-27 05:11:48 +00:00
32ef5517c2
Introduce a trivial, mostly empty <linux/sched/cputime.h> header to prepare for the moving of cputime functionality out of sched.h. Update all code that relies on these facilities. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
127 lines
3.3 KiB
C
127 lines
3.3 KiB
C
/*
|
|
* 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 <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;
|
|
|
|
trace_hardirqs_on();
|
|
|
|
/* 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);
|
|
|
|
/* Call the assembler magic in entry.S */
|
|
psw_idle(idle, psw_mask);
|
|
|
|
trace_hardirqs_off();
|
|
|
|
/* Account time spent with enabled wait psw loaded as idle time. */
|
|
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));
|
|
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)
|
|
{
|
|
struct s390_idle_data *idle = &per_cpu(s390_idle, dev->id);
|
|
unsigned long long now, idle_time, idle_enter, idle_exit;
|
|
unsigned int seq;
|
|
|
|
do {
|
|
now = get_tod_clock();
|
|
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));
|
|
idle_time += idle_enter ? ((idle_exit ? : now) - idle_enter) : 0;
|
|
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;
|
|
unsigned int seq;
|
|
|
|
do {
|
|
now = get_tod_clock();
|
|
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));
|
|
|
|
return cputime_to_nsecs(idle_enter ? ((idle_exit ?: now) - idle_enter) : 0);
|
|
}
|
|
|
|
void arch_cpu_idle_enter(void)
|
|
{
|
|
local_mcck_disable();
|
|
}
|
|
|
|
void arch_cpu_idle(void)
|
|
{
|
|
if (!test_cpu_flag(CIF_MCCK_PENDING))
|
|
/* Halt the cpu and keep track of cpu time accounting. */
|
|
enabled_wait();
|
|
local_irq_enable();
|
|
}
|
|
|
|
void arch_cpu_idle_exit(void)
|
|
{
|
|
local_mcck_enable();
|
|
if (test_cpu_flag(CIF_MCCK_PENDING))
|
|
s390_handle_mcck();
|
|
}
|
|
|
|
void arch_cpu_idle_dead(void)
|
|
{
|
|
cpu_die();
|
|
}
|