#printk — Public Fediverse posts

Linux 的 RT (Real-Time) 版本 PREEMPT_RT

在 Hacker News Daily 上看到的，Linux kernel 把 PREEMPT_RT 這個 RT patch 併入 official repository 了：「Real-time Linux is officially part of the kernel after decades of debate」。

這類需求可以在 RTOS 裡面看到完整的說明，大家常用的特性是確保反應時間這點，像是對汽車自動

https://blog.gslin.org/archives/2024/09/26/11993/linux-%e7%9a%84-rt-real-time-%e7%89%88%e6%9c%ac-preempt_rt/

#Computer #Linux #Murmuring #OS #Software #atomic #kernel #linux #output #patch #preempt_rt #printk #realtime #realtime

#PREEMPT_RT aka the #realtime support for #LinuxKernel hit #linux-next today! 🥳 👏

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/?qt=grep&q=PREEMPT_RT

Still remains to be seen if those changes really makes it upstream during the 6.12 merge window and stick:

* It afaics is still unclear if some #printk prerequisites will be submitted for 6.12: https://lore.kernel.org/all/87ed5za2oj[email protected]/

* Troublemaking changes sometimes are reverted before the final, which in fact happened to some of printk prerequisites a while ago: https://lore.kernel.org/lkml/202206231[email protected]/

#kernel

v6 of the patch-set "add threaded printing + the rest" which "provides the remaining pieces of the #printk rework."[1] is now in #Linux-next – but as of now it's not yet clear if this will be merged for #kernel 6.12.

https://lore.kernel.org/all/ZthvGoJE26[email protected]/

[1] e.g. the last big missing piece for #Realtime support through #PREEMPT_RT in the mainline #LinuxKernel. But note, this series does *not* provide an nbcon console driver. That will come in a follow-up series.

John posted v4 of the patch-set "threaded console printing as well as some other minor pieces" which "provides the remaining pieces of the #printk rework." -- e.g. the last big missing piece for #Realtime support through #PREEMPT_RT in the mainline #Linux #Kernel. But note, "this series does *not* provide an nbcon console driver. That will come in a follow-up series."

https://lore.kernel.org/all/2024082704[email protected]/

This comes hot on the heels of the "write_atomic() printing" entering -next: https://fosstodon.org/@kernellogger/113003819326920850

The improved #printk series "wire up write_atomic() printing" is now in -next again and thus slated for inclusion in #Linux 6.12. This is one of the last important bits for proper #REALTIME support with #PREEMPT_RT in mainline – but not the last, as this series does not include threaded printing or nbcon drivers, as those will come later: https://lore.kernel.org/all/ZsWxpVG8uZ[email protected]/

A earlier version of the patch set was supposed to go into #kernel 6.11, but Linus was unhappy: https://lore.kernel.org/lkml/CAHk-=whU[email protected]/

John posted v3 of the patch-set with the "remaining pieces of the #printk rework" to support threaded console printing, which is last big missing piece missing to support #realtime with the mainline #Linux #kernel through #PREEMPT_RT:

https://lore.kernel.org/all/2024072217[email protected]/

The last step in the #Linux #kernel #printk rework saga (the last big pre-requisite before #PREEMPT_RT can be mainlined) is getting closer:

John submitted the printk patch series "add threaded printing + the rest", which '"provides the remaining pieces of the printk rework. All other components are either already mainline or are currently in linux-next. […] Note that this series does *not* provide an nbcon console driver. That will come in a follow-up series."'

https://lore.kernel.org/all/2024060323[email protected]/