完整研究筆記 先釐清以下 (針對 kernel/bpf 目錄): kernel/bpf/bloom_filter.c 的設計考量; 為何使用 jhash，而非現有的 hash function? bpf 如何運用 bloom filter (注意: 這段程式碼由 Meta/Facebook 貢獻，因此一定有真實世界的應用場景)，Meta 內部大量使用 bloom filter 和 eBPF; 紀錄研讀 Documentation/bpf/map_bloom_filter.rst 的疑惑 (搭配 eBPF 閱讀) :::warning 確保你的 Linux 系統有超過 12 GB 的容量，你需要取得完整的 Linux 核心原始程式碼並進行實驗

參與者: bevmmf jserv 會議記錄 :::success 第六週測驗三提到的 bloom filter，其特性是沒有 false positive、抑或沒有 false negative? 為何 O(1) 的檢查很關鍵? :::

contributed by < bevmmf > :::danger 注意細節！ ::: 研讀 Linux 核心設計: 不只挑選任務的排程器 我覺得材料對 scheduler 的描述很有趣且直觀，「scheduler 就是一個數學函數，功能是映射 process 到系統資源」。單單要將此功能實現可能不難，但若是還需考慮性能規格如以下，那就不是件容易的事情。 性能規格

:::danger 說好的進度呢？ :::

contributed by <bevmmf> 預期目標 [ ] 檢驗學員對於 bitwise 操作及 rbtree 的熟悉程度 [ ] 檢驗學員對於 CS:APP 第二章的掌握：別忘了課程指定的教科書 [ ] 引導學員接觸 Linux 核心原始程式碼及解說應用案例 quiz3 測驗一 補完程式碼

實驗環境 Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Address sizes: 39 bits physical, 48 bits virtual Byte Order: Little Endian CPU(s): 12 On-line CPU(s) list: 0-11 Vendor ID: GenuineIntel Model name: Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz CPU family: 6

contributed by < bevmmf > quiz1 測驗 1 singly linked list struct #include <stddef.h> typedef struct list_item { int value; struct list_item *next;

contributed by < bevmmf > 依據 N02:ideas 之要求觀摩 Linux2024q1 期末專題、錄影上和錄影下。 觀摩專題一 : 排程器原理 (contributed by < jeremy90307 >) 一開始我先對這份專題進行蓋覽，並整理了這份專題做的幾個部分可分為以下 : 1. 探討 並行程式設計 對 Multiprogramming、Multitasking、Multithreading、Multiprocessing進行釐清

::: spoiler list_sort.c src // SPDX-License-Identifier: GPL-2.0 #include <linux/compiler.h> #include <linux/export.h> #include <linux/list_sort.h> #include <linux/list.h> /* * Returns a list organized in an intermediate format suited

In this section, I focused on implementing fundamental matrix operations commonly used in neural networks. Specifically, I developed functions for dot product, matrix multiplication, element-wise ReLU, and ArgMax. All matrices were represented as 1D vectors in row-major order. This representation required careful attention to memory access patterns, particularly when working with strides to access elements non-contiguously in memory. Challenges and Solutions 1. Input Handling: Flattening the 2D Matrix Challenge:Transforming a 2D matrix into a 1D vector was the first hurdle. Working with MNIST-like data, I had to ensure that the flattened representation accurately followed the row-major order. Solution:Through precise index calculations, I ensured that each row of the 2D matrix was concatenated correctly. This set a solid foundation for subsequent matrix operations.

Topic:function of checking if Bitwise OR Has Trailing Zeros topic discribtion and motivation discribtion Return true if it is possible to select two or more elements whose bitwise OR has trailing zeros, return false otherwise the function application In RISC-V instruction set, having trailing zeros in a piece of data can be an indicator that the data is not an executable instruction. This property arises because, in the RISC-V instruction format, the opcode (operation code) typically occupies the least significant 7 bits, and for standard RISC-V instructions, the least significant bit of the opcode is always set to 1. Thus, if a data word has a trailing zero (i.e., its least significant bit is 0), it can be inferred that it is unlikely to be a valid instruction opcode.This application is particularly useful during instruction decoding, where it helps distinguish between actual instructions and other types of data, such as immediate values, memory addresses, or control data. By quickly checking for trailing zeros, a processor or decoding logic can filter out non-instruction data and focus processing power on valid instructions only, which can enhance efficiency. C code Function-based programming