cregit-Linux how code gets into the kernel

Release 4.10 arch/s390/kernel/idle.c

Directory: arch/s390/kernel
/*
 * 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 <asm/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(idle_time); write_seqcount_end(&idle->seqcount); }

Contributors

PersonTokensPropCommitsCommitProp
martin schwidefskymartin schwidefsky9986.84%125.00%
frederic weisbeckerfrederic weisbecker108.77%125.00%
heiko carstensheiko carstens32.63%125.00%
linus torvaldslinus torvalds21.75%125.00%
Total114100.00%4100.00%

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 = ACCESS_ONCE(idle->idle_count); if (ACCESS_ONCE(idle->clock_idle_enter)) idle_count++; } while (read_seqcount_retry(&idle->seqcount, seq)); return sprintf(buf, "%llu\n", idle_count); }

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PersonTokensPropCommitsCommitProp
martin schwidefskymartin schwidefsky9190.10%150.00%
frederic weisbeckerfrederic weisbecker109.90%150.00%
Total101100.00%2100.00%

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 = ACCESS_ONCE(idle->idle_time); idle_enter = ACCESS_ONCE(idle->clock_idle_enter); idle_exit = ACCESS_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); }

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PersonTokensPropCommitsCommitProp
martin schwidefskymartin schwidefsky12792.70%150.00%
frederic weisbeckerfrederic weisbecker107.30%150.00%
Total137100.00%2100.00%

DEVICE_ATTR(idle_time_us, 0444, show_idle_time, NULL);
cputime64_t 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 = ACCESS_ONCE(idle->clock_idle_enter); idle_exit = ACCESS_ONCE(idle->clock_idle_exit); } while (read_seqcount_retry(&idle->seqcount, seq)); return idle_enter ? ((idle_exit ?: now) - idle_enter) : 0; }

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PersonTokensPropCommitsCommitProp
martin schwidefskymartin schwidefsky8989.90%150.00%
frederic weisbeckerfrederic weisbecker1010.10%150.00%
Total99100.00%2100.00%


void arch_cpu_idle_enter(void) { local_mcck_disable(); }

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martin schwidefskymartin schwidefsky10100.00%1100.00%
Total10100.00%1100.00%


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(); }

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martin schwidefskymartin schwidefsky22100.00%1100.00%
Total22100.00%1100.00%


void arch_cpu_idle_exit(void) { local_mcck_enable(); if (test_cpu_flag(CIF_MCCK_PENDING)) s390_handle_mcck(); }

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martin schwidefskymartin schwidefsky20100.00%1100.00%
Total20100.00%1100.00%


void arch_cpu_idle_dead(void) { cpu_die(); }

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martin schwidefskymartin schwidefsky10100.00%1100.00%
Total10100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
martin schwidefskymartin schwidefsky53091.38%120.00%
frederic weisbeckerfrederic weisbecker406.90%120.00%
heiko carstensheiko carstens81.38%240.00%
linus torvaldslinus torvalds20.34%120.00%
Total580100.00%5100.00%
Directory: arch/s390/kernel
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