perf/amd/ibs: Add PMU specific minimum period
authorRavi Bangoria <ravi.bangoria@amd.com>
Wed, 15 Jan 2025 05:44:35 +0000 (05:44 +0000)
committerPeter Zijlstra <peterz@infradead.org>
Mon, 3 Feb 2025 10:46:05 +0000 (11:46 +0100)
commitb2fc7b282bf7c1253b01c8da84e894539a3e709d
treea416bb8950d74839e057db722a378f20406a7e1c
parente1e7844ced88f9558a48579390a7d4eaac6a28eb
perf/amd/ibs: Add PMU specific minimum period

0x10 is the minimum sample period for IBS Fetch and 0x90 for IBS Op.
Current IBS PMU driver uses 0x10 for both the PMUs, which is incorrect.
Fix it by adding PMU specific minimum period values in struct perf_ibs.

Also, bail out opening a 'sample period mode' event if the user requested
sample period is less than PMU supported minimum value. For a 'freq mode'
event, start calibrating sample period from PMU specific minimum period.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/r/20250115054438.1021-7-ravi.bangoria@amd.com
arch/x86/events/amd/ibs.c