Re: [PATCH v4 11/32] drm/xe/log: Index all SIGID printk messages

On 13-08-2026 12:44 am, Michal Wajdeczko wrote:
> When CONFIG_PRINTK_INDEX is enabled, it is expected that all device
> level printk messages are indexed for audit. While usually this is
> done automatically behind the scenes when code is using regular
> dev_printk macros, since we are generating different dmesg messages
> inside xe_log_emit() based on the severity, component and location,
> we only get those entries in /sys/kernel/debug/printk/index/xe:
>
>    <3> drivers/gpu/drm/xe/xe_log.c:142 log_dmesg_vprintk "%s %s: [drm] *ERROR* %pV"
>    <6> drivers/gpu/drm/xe/xe_log.c:140 log_dmesg_vprintk "%s %s: [drm] %pV"
>
> Explicitly generate printk index using dev_printk_index_emit() with
> some generic prefix that includes the SIGID tag.
>
> Suggested-by: Jani Nikula <[email protected]>
> Signed-off-by: Michal Wajdeczko <[email protected]>
> Cc: Jani Nikula <[email protected]>
> Cc: Rodrigo Vivi <[email protected]>
> ---
>   drivers/gpu/drm/xe/xe_log.c |  8 ++++----
>   drivers/gpu/drm/xe/xe_log.h | 14 +++++++++++---
>   2 files changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_log.c b/drivers/gpu/drm/xe/xe_log.c
> index 0b423ed121cd..50a9b35e5b3e 100644
> --- a/drivers/gpu/drm/xe/xe_log.c
> +++ b/drivers/gpu/drm/xe/xe_log.c
> @@ -177,7 +177,7 @@ static void log_emit_dmesg(struct pci_dev *pdev, int cper_sev, enum xe_sigid sig
>   }
>   
>   /**
> - * xe_log_emit() - Emit a structured SIGID log entry
> + * __xe_log_emit() - Emit a structured SIGID log entry
>    * @pdev: the &pci_dev device
>    * @cper_sev: CPER severity (CPER_SEV_FATAL, CPER_SEV_RECOVERABLE, ...)
>    * @sigid: signature identifier, see &enum xe_sigid
> @@ -206,9 +206,9 @@ static void log_emit_dmesg(struct pci_dev *pdev, int cper_sev, enum xe_sigid sig
>    *   <3> xe 0000:03:00.0: [drm] *ERROR* SIGID=106 (-ETIMEDOUT) Engine 'rcs0' hung
>    *   <6> xe 0000:03:00.0: [drm] SIGID=103 In survivability mode
>    */
> -void xe_log_emit(struct pci_dev *pdev, int cper_sev, enum xe_sigid sigid,
> -		 u32 component, u32 location, const void *data, size_t len,
> -		 const char *fmt, ...)
> +void __xe_log_emit(struct pci_dev *pdev, int cper_sev, enum xe_sigid sigid,
> +		   u32 component, u32 location, const void *data, size_t len,
> +		   const char *fmt, ...)
>   {
>   	struct va_format vaf;
>   	va_list args;
> diff --git a/drivers/gpu/drm/xe/xe_log.h b/drivers/gpu/drm/xe/xe_log.h
> index 0928b0866617..53fe2bb7ddd3 100644
> --- a/drivers/gpu/drm/xe/xe_log.h
> +++ b/drivers/gpu/drm/xe/xe_log.h
> @@ -16,9 +16,17 @@
>   struct pci_dev;
>   
>   __printf(8, 9)
> -void xe_log_emit(struct pci_dev *pdev, int cper_sev, enum xe_sigid sigid,
> -		 u32 component, u32 location, const void *data, size_t len,
> -		 const char *fmt, ...);
> +void __xe_log_emit(struct pci_dev *pdev, int cper_sev, enum xe_sigid sigid,
> +		   u32 component, u32 location, const void *data, size_t len,
> +		   const char *fmt, ...);
> +
> +#define __xe_log_emit_printk_index(fmt) \
> +	dev_printk_index_emit(NULL, "[drm]%s SIGID=%u %s(%s)%s%s%s: " fmt);
We need to change format for a. error path b. blob path c. plain or info 
path right?
> +
> +#define xe_log_emit(pdev, sev, sig, comp, loc, data, len, fmt, args...) ({		\
> +	__xe_log_emit_printk_index(fmt);						\
> +	__xe_log_emit((pdev), (sev), (sig), (comp), (loc), (data), (len), fmt, ##args); \
> +})

nit: use do{} while (0)

Reviewed-by: Mallesh Koujalagi <[email protected]>

>   
>   #define xe_log_emit_fatal(pdev, sig, comp, loc, data, len, fmt, args...) \
>   	xe_log_emit((pdev), CPER_SEV_FATAL, (sig), (comp), (loc), \