I’m moving sceen.net to a smaller machine, and decided to shut down the Buildroot autobuilder that has been running on the server for more than 5 years now. Buildroot is a great project, with great people. I’ve been recommending it for more than a decade now, used it personally and professionally on multiple occasions, and was glad I could contribute that long despite very limited available time.
The project is still mostly stalled, unfortunately. But a couple of things were achieved :
- Simon Venken reported a bug on semaphores, which were reworked.
- Simon Venken also reported a bug concerning the chaining of wake-ups in sleep queues, which was fixed.
- the kern/mbuf module, providing message ring buffers, was added.
- the kern/log module was reworked to use a message ring buffer, and a bug on the log buffer being full was fixed.
How does a developer come up with code ? How does he know what to write, and if it’s a correct thing to do ? Spoiler alert: it’s much more art than science.Continue reading “Scenarios and invariants”
As a result of personal events, the project has been mostly stalled these last six months. However a few changes were made, the most important being :
- Interrupt handling rework on x86, with the merging of the trap module into the cpu module.
- Red zone support on x86 (amd64), which is required for full ABI compliance.
- Suspend/resume thread operations, similar to SIGSTOP/SIGCONT on Unix.
The major change of this quarter is the addition of a generic low level performance monitoring system, developed in large part by Rémy Noël.
It’s been a while since I’ve written about the progress on X15. As an open source project I work on in my free time, its development pace is unsurprisingly not constant, but despite that, a lot of progress was made since it was seriously restarted in 2017.
As my interest in the ARM architecture is growing, I decided to buy myself a toy to play with, based on one of those big.LITTLE asymmetric multicore 64-bit ARM processors, and see how they perform. I settled on the ASUS C101PA Chromebook after a friend successfully installed a Linux distribution on it.
I used to be an OVH DSL user. The service was very good. The only thing that could have been improved was the Technicolor router, which is clearly sub-par compared to the quality normally associated with OVH services, but as long as you stick to the default configuration, it would run fine. Continue reading “How bad can an ISP be ?”
Among the goals of the X15 operating system is real time. This expression is undoubtedly one of the vaguest buzzwords out there in the computer industry, which means I can’t really say anything about it without first attempting to provide a decent definition. Continue reading “Hey, real time !”