building an OS (all streams)

Currently Playing: building my own OS in c++ (week 128, kernel task sleep)

#livecoding #operatingsystem #coding welcome: https://offlinemark.com/welcome discord: https://discord.gg/P6zQBsD2ng Welcome! I’m an aspiring systems programmer. Professionally, I used to work in infosec, but now I work on music production software & hardware. I stream OS/kernel development every week for 2 hours. (I’ve done this for over 75 weeks in a row! Sundays 10a-12 ET) From February 2024 to May 2025, I streamed myself doing all the labs for MIT’s old Operating Systems Engineering course (6.828 (2018)). Through doing this, I became very familiar with JOS, which is the x86 OS used for the course. I had almost no experience with OS development when I started, although I did have much experience with programming and low level concepts. I did the coursework because I wanted to write my own OS, but felt I wasn’t ready. Now, from May 2025 to present, I’m pursuing my own learning agenda with OS development, and starting my on own OS. If this resonates with you, please subscribe and I'll see you in a stream :) 00:00:00 Start 00:06:07 - Reviewing the existing task waiting implementation in the scheduler code 00:15:53 - Proposing an inverted design where the waited-on task stores pointers to its waiters 00:23:03 - Creating a new git branch for the inverted implementation 00:26:50 - Coding the inverted waiting and waking mechanism in task exit 00:41:27 - Testing the new inverted implementation and confirming it works 00:42:07 - Comparing pros and cons of both task waiting implementations 00:56:07 - Analyzing race conditions between task exit and wait, and fixing with preemption disable 01:10:21 - Designing TSC-based sleep functionality using the timestamp counter 01:49:21 - Testing scheduler-integrated TSC sleep and discussing future plans including timer interrupts