News: 0001647541

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AMD Getting The Linux Kernel Ready For Zen 6 Profiling/Perf With More EILVT Registers

([AMD] 6 Hours Ago AMD Zen 6 Instruction Based Sampling)


Among the recent patch series in preparing Linux for upcoming AMD Zen 6 processors is making the kernel aware of additional EILVT registers to be found with at least EPYC Venice platforms.

Extended Interrupt Local Vector Table (EILVT) registers are used on AMD CPUs for Instruction-Based Sampling (IBS) for performance monitoring and profiling and Machine Check Exception (MCE) error reporting and similar roles. With Zen 6 processors, the EILVT table is being doubled from four to eight entries.

As part of preparing the Linux kernel for more EILVT registers, the code is being adapted to dynamically track the EILVT register count. [1]This patch series gets the Linux kernel ready for supporting the additional EILVT registers.

While not specifically laid out in the patches themselves, this addition is indeed for Zen 6 with the public [2]linked documentation outlining the Zen 6 IBS extensions and features coming for these next-gen processors. Zen 6 is also bringing new IBS filtering capabilities and other enhancements to benefit performance monitoring and profiling such as with Linux's perf infrastructure.

If all goes well these latest Zen 6 preparations could be merged for the upcoming Linux v7.3 kernel cycle.



[1] https://lore.kernel.org/lkml/cover.1784619898.git.naveen@kernel.org/

[2] https://docs.amd.com/v/u/en-US/69205_1.00_AMD64_IBS_PUB



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