today • Very quick review of concurrency and lock-free programming • Review the “bread and butter” of lock-free design patterns • Define wait-free algorithms, understand the definition and practical an elegant wait-free algorithm and wait-free design • Some simple benchmarks Some assumed knowledge • You know what std::atomic does and what it is used for • You’ve heard of lock-free programming and Obstruction free (progress in isolation): A single thread executed in isolation will complete the operation in a bounded number of steps. • Obstruction-free algorithms are immune to deadlock • Lock free (at

CPPCON 2020 / CPPCON 2020 / MACRO-FREE TESTING MACRO-FREE TESTING WITH C++20 WITH C++20 | | | | HTTPS://BOOST-EXT.GITHUB.IO/UT/CPPCON-2020 HTTPS://BOOST-EXT.GITHUB.IO/UT/CPPCON-2020 KRIS@JUSIAK SINGLE (2K LOC) WITH NO EXTERNAL DEPENDENCIES (2K LOC) WITH NO EXTERNAL DEPENDENCIES MACRO-FREE (✔ ) MACRO-FREE (✔ ) (*) LIMITATIONS MAY APPLY (*) LIMITATIONS MAY APPLY HTTPS://GITHUB.COM/BOOST-EXT/UT SINGLE (2K LOC) WITH NO EXTERNAL DEPENDENCIES (2K LOC) WITH NO EXTERNAL DEPENDENCIES MACRO-FREE (✔ ) MACRO-FREE (✔ ) FEATURES ( FEATURES ( , , , , , , , , , , , , , , ) (*) LIMITATIONS MAY APPLY

head) ● Busy polling on full / empty vs. sync using system calls ● Blocking / non blocking / wait-free ● Data ownership or just value propagation 13 CppCon 2024 | Erez Strauss | Lockfree, MPMC Queue instructions ● std::atomic - provides load / store / compare_exchange ● std::atomic::is_always_lock_free ● Load and Store of aligned 8 bytes ● CAS ( old-expected, new-value ) - atomic Compare And Swap

reliable sources such as Boost.Lockfree? ● Writing such a fifo is a fairly gentle introduction to lock free programming. ● There are some interesting performance optimizations that can be made. ● You may net/home/lock-free-algorithms/queues/unbounded-spsc-queue https://www.dpdk.org/ 3● Single producer: one producer (aka writer) thread ● Single consumer: one consumer (aka reader) thread ● Lock-free: it doesn’t doesn’t use mutex locks. At any point of time, some thread will make progress. ● Wait-free: each thread moves forward regardless of other threads. ● [Circular] Fifo [or Queue]: a single, fixed-size buffer

Deferred reclamation, i.e., garbage collection in C++ Some assumed knowledge • You’ve heard of lock-free programming and know what a compare_exchange is • You know roughly what atomic does and what it is Deferred reclamation, i.e., garbage collection in C++ Some assumed knowledge • You’ve heard of lock-free programming and know what a compare_exchange is • You know roughly what atomic does and what it is danielanderson.net std::atomic How many lines does it take to implement a lock-free & memory-safe stack? template struct Stack { struct Node { T t; shared_ptr

com/video/BV1fa411r7zp 课程 PPT 和代码： https://github.com/parallel101/course 前置条件 • 学过 C/C++ 语言编程。 • 理解 malloc/free 之类的概念。 • 熟悉 STL 中的容器、函数模板等。 • 英伟达 GTX900 及以上显卡。 • CUDA 11 及以上。 • CMake 3.18 及以上。 我负责监督你学习 第 TX1 / Tegra X1, Drive CX, Drive PX, Jetson Nano • 版本 60 ： Quadro GP100, Tesla P100, DGX-1 (Generic Pascal) • 版本 61 ： GTX 1080, GTX 1070, GTX 1060, GTX 1050, GTX 1030 (GP108), GT 1010 (GP108) Titan Xp GTX900 及以上显卡。如果需要在老显卡上运行的话 ，可以看下面那个链接，查一下你的显卡对应的版本号是多少 ，然后在 CMake 里设置个一样的，应该就能用了。 小彭老师每日锐评 • 顺便， Pascal 、 Turing 、 Ampere 什么的高大上架构名，那个是老黄拿来营销用的。 • 我们不考虑韭菜情怀的话不用管，我们只需要指定架构的版本号是多少就行啦。 • 毕竟一个 72 这样一个单

} // 在Win32 中CALLBACK 被定义为__stdcall，是一种函数调用习惯，关系到 // 参数挤压到堆栈的次序，以及处理堆栈的责任归属。其它的函数调用习惯还有 // _pascal 和_cdecl 当Windows 的「外壳」（shell，例如Windows 3.1 的程序管理员或Windows 95 的文件 总管）侦测到使用者意欲执行一个Windows 程序，于是调用加载器把该程序加载，然后 m_lpszClassName; int m_nObjectSize; UINT m_wSchema; // schema number of the loaded class CObject* (PASCAL* m_pfnCreateObject)(); // NULL => abstract class CRuntimeClass* m_pBaseClass; // CRuntimeClass #0004 #define LPCSTR LPSTR #0005 typedef char* LPSTR; #0006 #define UINT int #0007 #define PASCAL _stdcall #0008 #0009 #include #0010 #0011 class CObject; #0012 #0013 struct CRuntimeClass

more than an order of magnitude greater than that to be found within Pascal enterprises.” Alan J. Perlis Forward, SICP“Pascal is for building pyramids – imposing, breathtaking, static structures but it is incredibly rewarding and fun to solve them (in whichever language you choose) • IT IS FREE! (as well as the MIT & Berkeley Lectures)To all the passionate teachers that inspire • Gerald Sussman

banks, personal data, secrets, … Software safety (or “life safety” or similar) making software free from unacceptable risk of causing unintended harm to humans, property, or the environment examples: the available tools it presents to avoid undefined behavior in the C programs you write.” — Pascal Cuoq, Chief Scientist, Trustinsoft “An excellent introduction to modern C.” — Francis Glassborow the programmer can write it by hand, they’ll want to write it by generated code Examples: Types, free functions, specializations of std:: templates class(class) Foo { int func1(); public: void

kilogram * metre / square(second)> {} newton; inline constexpr struct pascal final : named_unit<"Pa", newton / square(metre)> {} pascal; inline constexpr struct joule final : named_unit<"J", newton * metre> kilogram * metre / square(second)> {} newton; inline constexpr struct pascal final : named_unit<"Pa", newton / square(metre)> {} pascal; inline constexpr struct joule final : named_unit<"J", newton * metre>