AMD Bus Lock Trap Support Merged For Linux 6.13
([AMD] 3 Hours Ago
AMD Bus Lock Trap)
- Reference: 0001507614
- News link: https://www.phoronix.com/news/AMD-Bus-Lock-Trap-Linux-6.13
- Source link:
Going back to early in the year AMD Linux engineers began [1]preparing support for a new Bus Lock Trap feature with Zen 5 CPUs . With the in-development Linux 6.13 kernel that support is being merged.
Years after Intel Linux engineers worked out the [2]split lock detection and [3]bus lock detection for the Linux kernel and their processors to [4]warn or kill on offending applications given the negative performance impact those locks can have on overall system performance, AMD Zen 5 systems running Linux 6.13+ will be able to leverage Bus Lock Trap.
[5]
The AMD Bus Lock Trap support with modern Ryzen/EPYC Zen 5 processors is now wired up with Linux 6.13. The Linux kernel code builds off the foundation laid out by Intel engineers. The AMD Bus Lock Trap feature will raise a #DB exception on occurrence of a bus lock when outside of the kernel (ring zero). Knowing about bus/split locks with either a warning or killing the app can be important for overall system performance health.
The work [6]had been queued ahead of Linux 6.12 but the tip/tip.git's x86/splitlock branch ultimately wasn't sent in for the prior merge window. This week though the code was [7]submitted and since [8]merged for Linux 6.13.
With Linux 6.13 the split lock detection and bus lock detection is also now behind a "CONFIG_X86_BUS_LOCK_DETECT" Kconfig build time switch for those wishing to toggle the support. More details on the functionality can be found via the [9]kernel documentation .
[1] https://www.phoronix.com/news/AMD-Bus-Lock-Trap-Detect-Linux
[2] https://www.phoronix.com/search/split%20lock
[3] https://www.phoronix.com/news/Linux-5.13-Lands-Intel-Bus-Lock
[4] https://www.phoronix.com/news/Linux-Split-Locks-Detection
[5] https://www.phoronix.com/image-viewer.php?id=2024&image=amd_turin_lock_lrg
[6] https://www.phoronix.com/news/AMD-Bus-Lock-Detect-Coming
[7] https://lore.kernel.org/lkml/ZzuBNj4JImJGUNJc@gmail.com/T/#u
[8] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0892d742132e09e132a501d3f54428f8ffd4b2b5
[9] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/arch/x86/buslock.rst?id=0892d742132e09e132a501d3f54428f8ffd4b2b5
Years after Intel Linux engineers worked out the [2]split lock detection and [3]bus lock detection for the Linux kernel and their processors to [4]warn or kill on offending applications given the negative performance impact those locks can have on overall system performance, AMD Zen 5 systems running Linux 6.13+ will be able to leverage Bus Lock Trap.
[5]
The AMD Bus Lock Trap support with modern Ryzen/EPYC Zen 5 processors is now wired up with Linux 6.13. The Linux kernel code builds off the foundation laid out by Intel engineers. The AMD Bus Lock Trap feature will raise a #DB exception on occurrence of a bus lock when outside of the kernel (ring zero). Knowing about bus/split locks with either a warning or killing the app can be important for overall system performance health.
The work [6]had been queued ahead of Linux 6.12 but the tip/tip.git's x86/splitlock branch ultimately wasn't sent in for the prior merge window. This week though the code was [7]submitted and since [8]merged for Linux 6.13.
With Linux 6.13 the split lock detection and bus lock detection is also now behind a "CONFIG_X86_BUS_LOCK_DETECT" Kconfig build time switch for those wishing to toggle the support. More details on the functionality can be found via the [9]kernel documentation .
[1] https://www.phoronix.com/news/AMD-Bus-Lock-Trap-Detect-Linux
[2] https://www.phoronix.com/search/split%20lock
[3] https://www.phoronix.com/news/Linux-5.13-Lands-Intel-Bus-Lock
[4] https://www.phoronix.com/news/Linux-Split-Locks-Detection
[5] https://www.phoronix.com/image-viewer.php?id=2024&image=amd_turin_lock_lrg
[6] https://www.phoronix.com/news/AMD-Bus-Lock-Detect-Coming
[7] https://lore.kernel.org/lkml/ZzuBNj4JImJGUNJc@gmail.com/T/#u
[8] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0892d742132e09e132a501d3f54428f8ffd4b2b5
[9] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/arch/x86/buslock.rst?id=0892d742132e09e132a501d3f54428f8ffd4b2b5
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