Re: [PATCH v8 2/6] cxl/trace: Add TRACE support for CXL media-error records

From: Ira Weiny
Date: Mon Mar 13 2023 - 18:51:27 EST


alison.schofield@ wrote:
> From: Alison Schofield <alison.schofield@xxxxxxxxx>
>
> CXL devices may support the retrieval of a device poison list.
> Add a new trace event that the CXL subsystem may use to log
> the media-error records returned in the poison list.
>
> Log each media-error record as a trace event of type 'cxl_poison'.
>
> Signed-off-by: Alison Schofield <alison.schofield@xxxxxxxxx>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> drivers/cxl/core/mbox.c | 4 +-
> drivers/cxl/core/trace.h | 84 ++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 87 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 0da0a30511f2..77fc811bdfed 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -1147,7 +1147,9 @@ int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
> if (rc)
> break;
>
> - /* TODO TRACE the media error records */
> + for (int i = 0; i < le16_to_cpu(po->count); i++)
> + trace_cxl_poison(cxlmd, cxlr, &po->record[i],
> + po->flags, po->overflow_t);
>
> /* Protect against an uncleared _FLAG_MORE */
> nr_records = nr_records + le16_to_cpu(po->count);
> diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h
> index 9b8d3d997834..33a22d26e742 100644
> --- a/drivers/cxl/core/trace.h
> +++ b/drivers/cxl/core/trace.h
> @@ -7,6 +7,7 @@
> #define _CXL_EVENTS_H
>
> #include <linux/tracepoint.h>
> +#include <linux/pci.h>
> #include <asm-generic/unaligned.h>
>
> #include <cxl.h>
> @@ -600,6 +601,89 @@ TRACE_EVENT(cxl_memory_module,
> )
> );
>
> +#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" })
> +
> +#define show_poison_source(source) \
> + (((source > CXL_POISON_SOURCE_INJECTED) && \
> + (source != CXL_POISON_SOURCE_VENDOR)) ? "Reserved" \
> + : __show_poison_source(source))
> +
> +#define show_poison_flags(flags) \
> + __print_flags(flags, "|", \
> + { CXL_POISON_FLAG_MORE, "More" }, \
> + { CXL_POISON_FLAG_OVERFLOW, "Overflow" }, \
> + { CXL_POISON_FLAG_SCANNING, "Scanning" })
> +
> +#define __cxl_poison_addr(record) \
> + (le64_to_cpu(record->address))
> +#define cxl_poison_record_dpa(record) \
> + (__cxl_poison_addr(record) & CXL_POISON_START_MASK)
> +#define cxl_poison_record_source(record) \
> + (__cxl_poison_addr(record) & CXL_POISON_SOURCE_MASK)
> +#define cxl_poison_record_length(record) \
> + (le32_to_cpu(record->length) * CXL_POISON_LEN_MULT)
> +#define cxl_poison_overflow(flags, time) \
> + (flags & CXL_POISON_FLAG_OVERFLOW ? le64_to_cpu(time) : 0)
> +
> +TRACE_EVENT(cxl_poison,
> +
> + TP_PROTO(struct cxl_memdev *cxlmd, struct cxl_region *region,
> + const struct cxl_poison_record *record,
> + u8 flags, __le64 overflow_t),

FWIW I made event overflow a separate trace event.

Will this make all of the poisons in a single GetPoison command marked
with overflow in the trace buffer?

Ira

> +
> + TP_ARGS(cxlmd, region, record, flags, overflow_t),
> +
> + TP_STRUCT__entry(
> + __string(memdev, dev_name(&cxlmd->dev))
> + __string(host, dev_name(cxlmd->dev.parent))
> + __field(u64, serial)
> + __string(region, region)
> + __field(u64, overflow_t)
> + __field(u64, dpa)
> + __field(u32, length)
> + __array(char, uuid, 16)
> + __field(u8, source)
> + __field(u8, flags)
> + ),
> +
> + TP_fast_assign(
> + __assign_str(memdev, dev_name(&cxlmd->dev));
> + __assign_str(host, dev_name(cxlmd->dev.parent));
> + __entry->serial = cxlmd->cxlds->serial;
> + __entry->overflow_t = cxl_poison_overflow(flags, overflow_t);
> + __entry->dpa = cxl_poison_record_dpa(record);
> + __entry->length = cxl_poison_record_length(record);
> + __entry->source = cxl_poison_record_source(record);
> + __entry->flags = flags;
> + if (region) {
> + __assign_str(region, dev_name(&region->dev));
> + memcpy(__entry->uuid, &region->params.uuid, 16);
> + } else {
> + __assign_str(region, "");
> + memset(__entry->uuid, 0, 16);
> + }
> + ),
> +
> + TP_printk("memdev=%s host=%s serial=%lld region=%s region_uuid=%pU dpa=0x%llx length=0x%x source=%s flags=%s overflow_time=%llu",
> + __get_str(memdev),
> + __get_str(host),
> + __entry->serial,
> + __get_str(region),
> + __entry->uuid,
> + __entry->dpa,
> + __entry->length,
> + show_poison_source(__entry->source),
> + show_poison_flags(__entry->flags),
> + __entry->overflow_t
> + )
> +);
> +
> #endif /* _CXL_EVENTS_H */
>
> #define TRACE_INCLUDE_FILE trace
> --
> 2.37.3
>