[Hygon] [devel-4.19] [Bugfix] Fix memory bandwidth counter width for Hygon QoS · Pull Request !6013 · anolis/cloud-kernel

bugzilla: https://bugzilla.openanolis.cn/show_bug.cgi?id=27057

**Issue and patch description:** 
Fix memory bandwidth counter width for Hygon CPUs

The memory bandwidth calculation relies on reading the hardware counter
and measuring the delta between samples. To ensure accurate measurement,
the software reads the counter frequently enough to prevent it from
rolling over twice between reads.

The default base counter width is 24. Currently, Hygon CPUs do not
support the CPUID 0xF.[ECX=1]:EAX to adjust the counter width. But the
Hygon CPUs support wider bandwidth counter with the default width of 32
bits.

Fix the issue by setting the default width to 32 bits (adjusting the
offset to 8 bits) for Hygon CPUs.

Fixes: 93ea79ade1df ("anolis: x86/resctrl: Add Hygon QoS support")

**Kernel config:** 
No kernel config changes for resctrl filesystem:
CONFIG_RESCTRL=y

**The steps to reproduce the issue:** 
Refer to the document in attachment：
https://bugzilla.openanolis.cn/attachment.cgi?id=1374

**Passed tests:** 
Resctrl filsystem - MBM test

类型	指派人员	状态
审查	xunlei 半叶枫尘 Artie Ding 冯光辉 Guixin Liu kun-llfl Xuchun Shang guochaohong yehuaisheng hygon-anolis-reviewers	已完成 (0/0人)
测试	小龙已测试通过	已完成 (1/1人)

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