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d20610c19b
IBS Op PMU on Zen5 uarch added new Load Latency filtering capability. It's advertised by CPUID_Fn8000001B_EAX bit 12. When enabled, IBS HW will raise interrupt only for sample that had an IbsDcMissLat value greater than N cycles, where N is a programmable value defined as multiples of 128 (i.e. 128, 256, 384 etc.) from 128-2048 cycles. Similar to L3MissOnly, IBS HW internally drops the sample and restarts if the sample does not meet the filtering criteria. Add support for LdLat filtering in IBS Op PMU. Since hardware supports threshold in multiple of 128, add a software filter on top to support latency threshold with the granularity of 1 cycle between [128-2048]. Example usage: # perf record -a -e ibs_op/ldlat=128/ -- sleep 5 Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250205060547.1337-2-ravi.bangoria@amd.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.