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I understand that your concern is about exposing= =0D implementation-defined registers to userspace, not simply choosing sysfs=0D versus debugfs. I'm not planning to submit v3.=0D =0D For controlled performance characterization, is there an existing kernel=0D mechanism or a different design you would recommend? Or do you think these= =0D experimental controls are better kept out of tree?=0D =0D Thanks,=0D Koba=0D