1. 주요 커널 기술

캐시

• Cache – Coherent
• AMBA AXI with ACE
• Barriers
• TLB Cache (API)

동기화

• Atomic Operation
• BKL(Big Kernel Lock)
• Exclusive loads and store
• Lockdep
• Lock Problem(Dead-Lock)
• Priority Inversion & Priority Inheritance
• Mutex for linux kernel space
• RCU(Read Copy Update) -1- (Basic)
• RCU(Read Copy Update) -2- (Callback process)
• RCU(Read Copy Update) -3- (RCU threads)
• RCU(Read Copy Update) -4- (NOCB process)
• RCU(Read Copy Update) -5- (Callback list)
• RCU(Read Copy Update) -6- (Expedited GP)
• RCU(Read Copy Update) -7- (Preemptible RCU)
• READ_ONCE() 및 WRITE_ONCE()와 lockless 리스트
• Spinlock

메모리 관리

• Bootmem with Bitmap
• Compound 페이지
• CMA(Contiguous Memory Allocator)
• CMA(Contiguous Memory Allocator) for DMA
• Early ioremap
• Fixmap
• GFP 플래그
• IDR(integer ID 관리)
• Ioremap
• Kmalloc
• Kmalloc vs Vmalloc
• Kmap(Pkmap)
• Memblock – (1)
• Memblock – (2)
• Memory Model -1- (Basic)
• Memory Model -2- (mem_map)
• Memory Model -3- (Sparse Memory)
• Memory Model -4- (APIs)
• NUMA -1- (ARM64 초기화)
• NUMA -2- (Fallback Node)
• NUMA -3- (Memory policy)
• Per-cpu -1- (Basic)
• Per-cpu -2- (초기화)
• Per-cpu -3- (동적 할당)
• Per-cpu -4- (atomic operations)
• Radix Tree
• Rmap -1- (Reverse Mapping)
• Rmap -2- (TTU & Rmap Walk)
• Rmap -3- (PVMW)
• Slub Memory Allocator -1- (구조)
• Slub Memory Allocator -2- (캐시 초기화)
• Slub Memory Allocator -3- (캐시 생성)
• Slub Memory Allocator -4- (Order 계산)
• Slub Memory Allocator -5- (Slub 할당)
• Slub Memory Allocator -6- (Object 할당)
• Slub Memory Allocator -7- (Object 해제)
• Slub Memory Allocator -8- (Drain/Flash 캐시)
• Slub Memory Allocator -9- (캐시 Shrink)
• Slub Memory Allocator -10- (Slub 해제)
• Slub Memory Allocator -11- (캐시 삭제)
• Slub Memory Allocator -12- (Slub 디버깅)
• Slub Memory Allocator -13- (slabinfo)
• Swap -1- (Basic, 초기화)
• Swap -2- (Swapin & Swapout)
• Swap -3- (Swap 영역 할당/해제)
• Swap -4- (Swap 엔트리)
• User virtual maps (brk)
• User virtual maps (mmap)
• Vmalloc
• Vmap
• VMPressure
• Zone 타입
• Zoned Allocator -1- (물리 페이지 할당-Fastpath)
• Zoned Allocator -2- (물리 페이지 할당-Slowpath)
• Zoned Allocator -3- (Buddy 페이지 할당)
• Zoned Allocator -4- (Buddy 페이지 해지)
• Zoned Allocator -5- (Per-cpu Page Frame Cache)
• Zoned Allocator -6- (Watermark)
• Zoned Allocator -7- (Direct Compact)
• Zoned Allocator -8- (Direct Compact-Isolation)
• Zoned Allocator -9 (Direct Compact-Migration)
• Zoned Allocator -10- (LRU & pagevecs)
• Zoned Allocator -11- (Direct Reclaim)
• Zoned Allocator -12- (Direct Reclaim-Shrink-1)
• Zoned Allocator -13- (Direct Reclaim-Shrink-2)
• Zoned Allocator -14- (Kswapd & Kcompactd)

ARM & 페이지 테이블 매핑

• 32비트 ARM에서의 user space vs kernel space
• ARM32 페이지 테이블 -1- (Basic)
• ARM32 페이지 테이블 -2- (매핑)
• ARM32 페이지 테이블 -3- (API)
• ARM32 페이지 테이블 -4- (엔트리 속성)
• ARM64 페이지 테이블 -1- (Basic)
• ARM64 페이지 테이블 -2- (매핑)
• ARM64 페이지 테이블 -3- (API)
• Exception -1- (ARM32 Vector)
• Exception -2- (ARM32 Handler 1)
• Exception -3- (ARM32 Handler 2)
• Exception -4- (ARM32 VFP & FPE)
• Exception -5- (Extable)
• Exception -6- (MM Fault Handler)
• Exception -7- (ARM64 Vector)
• Exception -8- (ARM64 Handler)
• ARM 시스템 주요 레지스터
• ARM64 시스템 주요 레지스터
• Memory Access Order Type & Shareable Region
• ARMv8 & ARMv9 아키텍처 extension

클럭, 타이머, 인터럽트

• Common Clock Framework -1- (초기화)
• Common Clock Framework -2- (APIs)
• Interrupts -1- (Interrupt Controller)
• Interrupts -2- (irq chip)
• Interrupts -3- (irq domain)
• Interrupts -4- (Top-Half & Bottom-Half)
• Interrupts -5- (Softirq)
• Interrupts -6- (IPI Cross-call)
• Interrupts -7- (Workqueue 1)
• Interrupts -8- (Workqueue 2)
• Interrupts -9- (GIC v3 Driver)
• Interrupts -10- (irq partition)
• Interrupts -11- (RPI2 IC Driver)
• Interrupts -12- (irq desc)
• Timer -1- (Lowres Timer)
• Timer -2- (HRTimer)
• Timer -3- (Clock Sources Subsystem)
• Timer -4- (Clock Sources Watchdog)
• Timer -5- (Clock Events Subsystem)
• Timer -6- (Clock Source & Timer Driver)
• Timer -7- (Sched Clock & Delay Timers)
• Timer -8- (Timecounter)
• Timer -9- (Tick Device)
• Timer -10- (Timekeeping)
• Timer -11- (Posix Clock & Timers)

스케줄러

• Scheduler -1- (Basic)
• Scheduler -2- (Global Cpu Load)
• Scheduler -3- (PELT-1)
• Scheduler -3a- (PELT-2)
• Scheduler -4- (Group Scheduling)
• Scheduler -5- (Scheduler Core)
• Scheduler -6- (CFS Scheduler)
• Scheduler -7- (Preemption & Context Switch)
• Scheduler -8- (CFS Bandwidth)
• Scheduler -9- (RT Scheduler)
• Scheduler -10- (Deadline Scheduler)
• Scheduler -11- (Stop Scheduler)
• Scheduler -12- (Idle Scheduler)
• Scheduler -13- (Scheduling Domain 1)
• Scheduler -14- (Scheduling Domain 2)
• Scheduler -15- (Load Balance 1)
• Scheduler -16- (Load Balance 2)
• Scheduler -17- (Load Balance 3 NUMA)
• Scheduler -18- (Load Balance 4 EAS)
• Scheduler -19- (초기화)
• PID 관리
• do_fork()
• cpu_startup_entry() – cpuidle | 문c
• 런큐 로드 평균(cpu_load[]) – v4.0
• PELT(Per-Entity Load Tracking) – v4.0

디바이스 트리 및 드라이버

• Console & TTY Driver
• Device & Driver -1- (Basic)
• Device & Driver -2- (Bus & Class)
• Device & Driver -3- (Platform Device)
• Device Resource Management
• devtmpfs & kdevtmpfs 스레드
• DMA -1- (Basic)
• DMA -2- (DMA Coherent Memory)
• DMA -3- (DMA Pool)
• DMA -4- (DMA Mapping)
• DMA -5- (IOMMU)
• DMA -6- (DMAEngine Subsystem)
• DTB – 구조
• DTB – 라즈베리파이 2
• DTB – 라즈베리파이 4
• DTB (fdt API)
• DTB (of API)
• Earlycon & Earlyprintk
• I2C Subsystem -1- (Basic)
• I2C Subsystem -2- (Core)
• I2C Subsystem -3- (Transfer)
• I2C Subsystem -4- (I2C-Mux)
• IOMMU
• GPIO Subsystem -1-
• GPIO Subsystem -2-
• GPIO Subsystem -3- (Device Tree)
• GPIO Subsystem -4- (new Interface)
• MTD(Memory Technology Device) -1-
• MTD(Memory Technology Device) -2-
• MTD(Memory Technology Device) -3-
• PCI Subsystem -1- (Basic)
• PCI Subsystem -2- (Core)
• PCI Subsystem -3- (Host Controller)
• Pin Control Subsystem -1-
• Pin Control Subsystem -2-
• Proc interface & seq_file
• SPI Subsystem -1- (Basic)
• SPI Subsystem -2- (Driver)
• Sysfs (kobject & kset)

디버그

• FTrace
• Kernel Debugging
• Kernel Tracing
• Kprobe
• Profiling
• Sparse 정적 분석 도구
• TRACE_EVENT
• 디버그 메모리 -1- (Page Alloc)
• 디버그 메모리 -2- (Page Poisoning)
• 디버그 메모리 -3- (Page Owner 추적)
• 디버그 메모리 -4- (Idle Page 추적)

커널 관리 확장

• Control Groups
• Docker vs LXC vs Hypervisor
• Control Group for Memory
• LSM(Linux Security Module) -1-
• LIM(Linux Integrity Module) -1-
• Namespace

기타

• Addressing Mode (AArch64)
• Bit Operations
• Bitmap Operations
• CPU Capabilities – ARM64
• CPU 비트맵 (API)
• ELF Relocations (AArch64)
• Freeze (hibernation/suspend)
• Inline Assembly
• Kernel-provided User Helpers
• Likely & Unlikely
• NODE 비트맵 (API)
• QEMU 에뮬레이션(arm64)
• Static Keys -1- (Core API)
• Static Keys -2- (초기화)
• User stack vs Kernel stack
• VMSA Fault Checking
• Volatile
• 커널 코드 영역 확인(func_ptr_is_kernel_text())
• 함수 선언부 관련 매크로 (__attribute__)
• 가상화 지원 (하이퍼 모드)
• 어셈블리(head.S) – gdb 디버깅 방법