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
IBS support has been enhanced with two new features in upcoming uarch:
1. DataSrc extension and
2. L3 miss filtering.
Additional set of bits has been introduced in IBS registers to use these
features. Define these new bits into arch/x86/ header.
[ bp: Massage commit message. ]
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20220604044519.594-7-ravi.bangoria@amd.com
