Re: [PATCH 2/3] cxl: Introduce module parameter 'enable_psltrace'
From: Vaibhav Jain <hidden>
Date: 2018-02-11 17:10:32
Thanks for reviewing the patch Christophe, christophe lombard [off-list ref] writes:
quoted
+bool cxl_enable_psltrace = true; +module_param_named(enable_psltrace, cxl_enable_psltrace, bool, 0600); +MODULE_PARM_DESC(enable_psltrace, "Set PSL traces on probe. default: on"); +I am not too agree to add a new parameter. This can cause doubts. PSL team has confirmed that enabling traces has no impact. Do you see any reason to disable the traces ?
Traces on PSL follow a 'set and fetch' model. So once the trace buffer for a specific array is full it will stop and switch to 'FIN' state and at that point we need to fetch the trace-data and reinit the array to re-arm it. There might be some circumstances where this model may lead to confusion specifically when AFU developers assume that the trace arrays are already armed and dont re-arm it causing miss of trace data. So this module param is a compromise to keep the old behaviour of traces array intact where in the arming/disarming of the trace arrays is controlled completely by userspace tooling and not by cxl. -- Vaibhav Jain [off-list ref] Linux Technology Center, IBM India Pvt. Ltd.