Re: [PATCH v4 13/15] cxl/pci: Add trace logging for CXL PCIe Port RAS errors

[Alejandro Lucero Palau <alucerop@xxxxxxx>]

On 12/11/24 23:40, Terry Bowman wrote:
> The CXL drivers use kernel trace functions for logging endpoint and RCH
> Downstream Port RAS errors. Similar functionality is required for CXL Root
> Ports, CXL Downstream Switch Ports, and CXL Upstream Switch Ports.
>
> Introduce trace logging functions for both RAS correctable and
> uncorrectable errors specific to CXL PCIe Ports. Additionally, update
> the PCIe Port error handlers to invoke these new trace functions.
>
> Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>


Reviewed-by: Alejandro Lucero <alucerop@xxxxxxx>


> ---
>   drivers/cxl/core/pci.c   | 16 ++++++++++----
>   drivers/cxl/core/trace.h | 47 ++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 59 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 52afaedf5171..3294ad5ff28f 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -661,10 +661,14 @@ static void __cxl_handle_cor_ras(struct device *dev,
>   
>   	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>   	status = readl(addr);
> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
> +		return;
> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> +
> +	if (is_cxl_memdev(dev))
>   		trace_cxl_aer_correctable_error(to_cxl_memdev(dev), status);
> -	}
> +	else
> +		trace_cxl_port_aer_correctable_error(dev, status);
>   }
>   
>   static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)
> @@ -720,7 +724,11 @@ static bool __cxl_handle_ras(struct device *dev, void __iomem *ras_base)
>   	}
>   
>   	header_log_copy(ras_base, hl);
> -	trace_cxl_aer_uncorrectable_error(to_cxl_memdev(dev), status, fe, hl);
> +	if (is_cxl_memdev(dev))
> +		trace_cxl_aer_uncorrectable_error(to_cxl_memdev(dev), status, fe, hl);
> +	else
> +		trace_cxl_port_aer_uncorrectable_error(dev, status, fe, hl);
> +
>   	writel(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK, addr);
>   
>   	return true;
> diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h
> index 8389a94adb1a..681e415ac8f5 100644
> --- a/drivers/cxl/core/trace.h
> +++ b/drivers/cxl/core/trace.h
> @@ -48,6 +48,34 @@
>   	{ CXL_RAS_UC_IDE_RX_ERR, "IDE Rx Error" }			  \
>   )
>   
> +TRACE_EVENT(cxl_port_aer_uncorrectable_error,
> +	TP_PROTO(struct device *dev, u32 status, u32 fe, u32 *hl),
> +	TP_ARGS(dev, status, fe, hl),
> +	TP_STRUCT__entry(
> +		__string(devname, dev_name(dev))
> +		__string(host, dev_name(dev->parent))
> +		__field(u32, status)
> +		__field(u32, first_error)
> +		__array(u32, header_log, CXL_HEADERLOG_SIZE_U32)
> +	),
> +	TP_fast_assign(
> +		__assign_str(devname);
> +		__assign_str(host);
> +		__entry->status = status;
> +		__entry->first_error = fe;
> +		/*
> +		 * Embed the 512B headerlog data for user app retrieval and
> +		 * parsing, but no need to print this in the trace buffer.
> +		 */
> +		memcpy(__entry->header_log, hl, CXL_HEADERLOG_SIZE);
> +	),
> +	TP_printk("device=%s host=%s status: '%s' first_error: '%s'",
> +		  __get_str(devname), __get_str(host),
> +		  show_uc_errs(__entry->status),
> +		  show_uc_errs(__entry->first_error)
> +	)
> +);
> +
>   TRACE_EVENT(cxl_aer_uncorrectable_error,
>   	TP_PROTO(const struct cxl_memdev *cxlmd, u32 status, u32 fe, u32 *hl),
>   	TP_ARGS(cxlmd, status, fe, hl),
> @@ -96,6 +124,25 @@ TRACE_EVENT(cxl_aer_uncorrectable_error,
>   	{ CXL_RAS_CE_PHYS_LAYER_ERR, "Received Error From Physical Layer" }	\
>   )
>   
> +TRACE_EVENT(cxl_port_aer_correctable_error,
> +	TP_PROTO(struct device *dev, u32 status),
> +	TP_ARGS(dev, status),
> +	TP_STRUCT__entry(
> +		__string(devname, dev_name(dev))
> +		__string(host, dev_name(dev->parent))
> +		__field(u32, status)
> +	),
> +	TP_fast_assign(
> +		__assign_str(devname);
> +		__assign_str(host);
> +		__entry->status = status;
> +	),
> +	TP_printk("device=%s host=%s status='%s'",
> +		  __get_str(devname), __get_str(host),
> +		  show_ce_errs(__entry->status)
> +	)
> +);
> +
>   TRACE_EVENT(cxl_aer_correctable_error,
>   	TP_PROTO(const struct cxl_memdev *cxlmd, u32 status),
>   	TP_ARGS(cxlmd, status),