Linux 5.0 new feature:https://kernelnewbies.org/Linux_5.0#Energy-aware_Scheduling_for_Arm_big.LITTLE 732cd75 sched/fair: Select an energy-efficient CPU on task wake-up 390031e4 sched/fair: Introdu...

一、关键数据结构 task event enum task_event { PUT_PREV_TASK = 0, PICK_NEXT_TASK = 1, TASK_WAKE = 2, TASK_MIGRATE = 3, TASK_UPDATE = 4, IRQ_UPDATE = 5,}; ravg /* ravg represents frequency sca...

Utilizationclamping把cpu的util钳位到[util_min,util_max]范围内，util_min,util_max取决于cpu上的runnable task；每个task使用两个clampbuckets定义该task的最大/最小utilization钳位值util_{min,max}。 每个cpu有5个（默认值）uclamp_bucket， rq上的定义...

eas_one_small_task setup阶段：configure and enable tracing(/sys/kernel/tracing): 分析解析后的trace 加载trace，并按定义的结构体struct trace_record{}格式进行解析 echo 0 > tracing_on //disable tracing 创建一个while(1) task eas_one_small_t，每sleep 1ms起来...

sugov_get_util\--> boosted_cpu_util \--> schedtune_cpu_margin(util, cpu) \-->schedtune_cpu_boost schedtune_margin(util, boost) trace_sched_boost_cpu(cpu, util, margin)select_idle_sibling_cs...

测试用例图示测试用例源码1 /* 2 * Copyright (c) 2018 Google, Inc. 3 * 4 * SPDX-License-Identifier: GPL-2.0-or-later 5 * 6 * Task starts out as a CPU hog and then becomes small. 7 * Task placement and downmigration latency are verified. 8 *...

cpu_scale的意义 49 CPU0: cpu@0 {50 device_type = "cpu";51 compatible = "arm,cortex-a55";52 reg = <0x0 0x0>;53 enable-method = "psci";54 cpu-idle-states = <&CORE_PD>;55 cpufreq-data-v1 = <&cpufreq_cluster0_..

一、数据结构１．root_domain初始化函数调用关系start_kernel() \-sched_init(void) \-init_defrootdomain(); \-init_rootdomain(&def_root_domain)start_kernel() \-arch_call_rest_init() \-rest_init() \-kernel_init \-kernel_init_freeable(

https://lkml.org/lkml/2017/7/6/268

10a35e6 sched/pelt: Skip updating util_est when utilization is higher than CPU's capacity2312729 sched/fair: Update scale invariance of PELT62478d9 sched/fair: Move the rq_of() helper function

519329 sched/fair: Update util_est only on util_avg updatesa07630b sched/cpufreq/schedutil: Use util_est for OPP selectionf9be3e5 sched/fair: Use util_est in LB and WU paths7f65ea4 sched/fair: Add ...

757ffdd sched/fair: Set rq->rd->overload when misfite90c8fe sched/fair: Wrap rq->rd->overload accesses with READ/WRITE_ONCE()575638d sched/core: Change root_domain->overload type to i...

AOSP Kernel4.14已经有这个feature，kernel4.20参考AOSP kernel也支持这个feature：e1799a8 sched/topology, arch/arm: Rebuild sched_domain hierarchy when CPU capacity changes3ba09df sched/topology, arch/arm64: Rebuild...

（一）简介：测试前取/sys/devices/system/cpu/cpufreq/policy4/stats/time_in_state（个cpu频点及运行时间: Documentation/cpu-freq/cpufreq-stats.txt）和/proc/stat（各cpu不同state的时间）数据，测试开始，测试程序sleep指定的测试时间，测试结束，再次获取测试结束时的节点数据，进行...

摘要：    在学习linux内核代码及一些开源软件的源码（如：DirectFB），经常可以看到有关__attribute__的相关使用。本文结合自己的学习经历，较为详细的介绍了__attribute__相关语法及其使用。----------------------------------------------------------------声明：    此文为原创，欢迎

(ZT)GNU C 的 __attribute__ 机制2011-11-10 19:02----------------------------------------------------------------    原作者：    初次发布时间：2006-06-17  修改者：-------------------------------------------

============================================作者：yuanluluhttp://blog.youkuaiyun.com/yuanlulu版权没有，但是转载请保留此段声明============================================1。网上遇到的一个问题。先贴出来问题，再说解决方法。看“linux 内核设计与实

start_kernel()--void timer_tick(void)   //为Kernel提供的体系架构无关的、系统相关的时钟中断处理函数,通常会在体系架构相关的时钟中断处理函数内调用它。参考1；{    profile_tick(CPU_PROFILING);//调用profile_tick()监管内核代码    do_leds();    write_se

static ssize_t state_store(){suspend_state_t state = PM_SUSPEND_ON;+----------------------------------------------------------------------------------------- 30 typedef int __bitwise s

FOTA--无线固件升级APCS--arm过程调用标准linux内核的数据结构：3 每CPU变量http://lwn.net/Articles/433002/http://www.kerneltravel.net/https://psfthcm.vanceinfo.com:4460/psp/hcmprd/EMPLOYEE/HRMS/?cmd=login&languageCd

首先从这里开始： static int __init pm8058_rtc_init(void){ return platform_driver_register(&pm8058_rtc_driver);}//__init标志对内核来讲是一个暗示,表明该函数只是在初始化时使用。模块加载器在模块加载后会丢掉这个初始化函数,这样可将该函数占用的内存释放出来，以作他用。1----

使用arm-eabi-addr2line把函数地址解析为函数名称:$prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin$/arm-eabi-addr2line -f -e vmlinux 803a3f40输出$mdp_early_suspend$/home/CORPUSERS/28851277/project/linux-fujir3-0