Zack's Kernel News
Zack's Kernel News
Chronicler Zack Brown reports Opcode life cycles and naming conventions.
Opcode Life Cycles
In the Mariana Trench of Linux kernel development swims the elusive yet luminescent creature, the opcode. Rarely seen by user eyes, the opcode forms the basis of the elaborate computer ecosystem upon which rests the digital life and productivity of our entire planet.
Opcodes exist at the hardware level. They are implemented by the actual AND, OR, and other silicon-based logic gates that exist by the millions on chips that run nearly every CPU in the known universe. Quantum computers, Babbage difference engines, and Antikythera devices are something else again – Linux support coming soon.
Steven Rostedt recently caught a glimpse of the rare and elusive cmpxchg opcode. This opcode compares and then potentially exchanges two values with one another, without allowing anything to interrupt it during the moment between the comparison and the actual data exchange. Ordinarily, in Linux and other multithreaded systems, operations are routinely interrupted by the kernel to provide that smooth and seamless feel of everyone using the system at the same time. The cmpxchg opcode makes this easier by preventing the interruption coming at an inconvenient moment, when the data might be in an inconsistent state. Otherwise, the kernel would have to implement a more complex and robust batch of code to do the same operation safely.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
There's a New Linux AI Assistant in Town
Newelle is a Linux AI assistant that can work with different LLMs and includes document parsing and profiles.
-
Linux Kernel 6.16 Released with Minor Fixes
The latest Linux kernel doesn't really include any big-ticket features, just a lot of lines of code.
-
EU Sovereign Tech Fund Gains Traction
OpenForum Europe recently released a report regarding a sovereign tech fund with backing from several significant entities.
-
FreeBSD Promises a Full Desktop Installer
FreeBSD has lacked an option to include a full desktop environment during installation.
-
Linux Hits an Important Milestone
If you pay attention to the news in the Linux-sphere, you've probably heard that the open source operating system recently crashed through a ceiling no one thought possible.
-
Plasma Bigscreen Returns
A developer discovered that the Plasma Bigscreen feature had been sitting untouched, so he decided to do something about it.
-
CachyOS Now Lets Users Choose Their Shell
Imagine getting the opportunity to select which shell you want during the installation of your favorite Linux distribution. That's now a thing.
-
Wayland 1.24 Released with Fixes and New Features
Wayland continues to move forward, while X11 slowly vanishes into the shadows, and the latest release includes plenty of improvements.
-
Bugs Found in sudo
Two critical flaws allow users to gain access to root privileges.
-
Fedora Continues 32-Bit Support
In a move that should come as a relief to some portions of the Linux community, Fedora will continue supporting 32-bit architecture.