RE: [PATCH 1/3] trace, cxl: Introduce a TRACE_EVENT for CXL Poison Records

From: Dan Williams
Date: Fri Jun 17 2022 - 14:04:54 EST


alison.schofield@ wrote:
> From: Alison Schofield <alison.schofield@xxxxxxxxx>
>
> Add a trace event for CXL Poison List Media Error Records that
> includes the starting DPA of the poison, the length, and the
> the source of the poison.
>
> This trace event will be used by the CXL_MEM driver to log the
> Media Errors returned by the GET_POISON_LIST Mailbox command.
>
> Signed-off-by: Alison Schofield <alison.schofield@xxxxxxxxx>
> ---
> include/trace/events/cxl.h | 60 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 60 insertions(+)
> create mode 100644 include/trace/events/cxl.h
>
> diff --git a/include/trace/events/cxl.h b/include/trace/events/cxl.h
> new file mode 100644
> index 000000000000..17e707c3817e
> --- /dev/null
> +++ b/include/trace/events/cxl.h
> @@ -0,0 +1,60 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM cxl
> +
> +#if !defined(_CXL_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _CXL_TRACE_H
> +
> +#include <linux/tracepoint.h>
> +
> +TRACE_DEFINE_ENUM(CXL_POISON_SOURCE_UNKNOWN);
> +TRACE_DEFINE_ENUM(CXL_POISON_SOURCE_INTERNAL);
> +TRACE_DEFINE_ENUM(CXL_POISON_SOURCE_EXTERNAL);
> +TRACE_DEFINE_ENUM(CXL_POISON_SOURCE_INJECTED);
> +TRACE_DEFINE_ENUM(CXL_POISON_SOURCE_VENDOR);
> +TRACE_DEFINE_ENUM(CXL_POISON_SOURCE_INVALID);
> +
> +#define show_poison_source(source) \
> + __print_symbolic(source, \
> + {CXL_POISON_SOURCE_UNKNOWN, "UNKNOWN"}, \
> + {CXL_POISON_SOURCE_EXTERNAL, "EXTERNAL"}, \
> + {CXL_POISON_SOURCE_INTERNAL, "INTERNAL"}, \
> + {CXL_POISON_SOURCE_INJECTED, "INJECTED"}, \
> + {CXL_POISON_SOURCE_VENDOR, "VENDOR"}, \
> + {CXL_POISON_SOURCE_INVALID, "INVALID"})
> +
> +TRACE_EVENT(cxl_poison_list,
> +
> + TP_PROTO(struct device *dev,

The CXL memory device names need some decoding before other userspace
RAS tools might know what they are. So in addition to
dev_name(&cxlmd->dev) I think it would be useful to include
dev_name(cxlmd->dev.parent), i.e. the host PCI device name.

Other than that, looks good to me.

> + int source,
> + unsigned long start,
> + unsigned int length),
> +
> + TP_ARGS(dev, source, start, length),
> +
> + TP_STRUCT__entry(
> + __string(name, dev_name(dev))
> + __field(int, source)
> + __field(u64, start)
> + __field(u32, length)
> + ),
> +
> + TP_fast_assign(
> + __assign_str(name, dev_name(dev));
> + __entry->source = source;
> + __entry->start = start;
> + __entry->length = length;
> + ),
> +
> + TP_printk("dev %s source %s start %llu length %u",
> + __get_str(name),
> + show_poison_source(__entry->source),
> + __entry->start,
> + __entry->length)
> +);
> +#endif /* _CXL_TRACE_H */
> +
> +/* This part must be outside protection */
> +#undef TRACE_INCLUDE_FILE
> +#define TRACE_INCLUDE_FILE cxl
> +#include <trace/define_trace.h>
> --
> 2.31.1
>