Re: [PATCH v6 3/7] cxl/event_trace: add a private context for private parsers

From: Dave Jiang <dave.jiang@intel.com>
To: <alison.schofield@intel.com>, Vishal Verma <vishal.l.verma@intel.com>
Cc: <nvdimm@lists.linux.dev>, <linux-cxl@vger.kernel.org>
Subject: Re: [PATCH v6 3/7] cxl/event_trace: add a private context for private parsers
Date: Fri, 19 Jan 2024 14:08:16 -0700	[thread overview]
Message-ID: <937beafe-a5dc-4537-98d4-ffd4af332d2f@intel.com> (raw)
In-Reply-To: <e1bc45fa032226407dbc2f75c552f12f07c8c829.1705534719.git.alison.schofield@intel.com>


On 1/17/24 17:28, alison.schofield@intel.com wrote:
> From: Alison Schofield <alison.schofield@intel.com>
> 
> CXL event tracing provides helpers to iterate through a trace
> buffer and extract events of interest. It offers two parsing
> options: a default parser that adds every field of an event to
> a json object, and a private parsing option where the caller can
> parse each event as it wishes.
> 
> Although the private parser can do some conditional parsing based
> on field values, it has no method to receive additional information
> needed to make parsing decisions in the callback.
> 
> Add a private_ctx field to the existing 'struct event_context'.
> Replace the jlist_head parameter, used in the default parser,
> with the private_ctx.
> 
> This is in preparation for adding a private parser requiring
> additional context for cxl_poison events.
> 
> Signed-off-by: Alison Schofield <alison.schofield@intel.com>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
>  cxl/event_trace.c | 2 +-
>  cxl/event_trace.h | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/cxl/event_trace.c b/cxl/event_trace.c
> index 269060898118..fbf7a77235ff 100644
> --- a/cxl/event_trace.c
> +++ b/cxl/event_trace.c
> @@ -215,7 +215,7 @@ static int cxl_event_parse(struct tep_event *event, struct tep_record *record,
>  
>  	if (event_ctx->parse_event)
>  		return event_ctx->parse_event(event, record,
> -					      &event_ctx->jlist_head);
> +					      event_ctx->private_ctx);
>  
>  	return cxl_event_to_json(event, record, &event_ctx->jlist_head);
>  }
> diff --git a/cxl/event_trace.h b/cxl/event_trace.h
> index 7f7773b2201f..ec61962abbc6 100644
> --- a/cxl/event_trace.h
> +++ b/cxl/event_trace.h
> @@ -16,8 +16,9 @@ struct event_ctx {
>  	struct list_head jlist_head;
>  	const char *event_name; /* optional */
>  	int event_pid; /* optional */
> +	void *private_ctx; /* required with parse_event() */
>  	int (*parse_event)(struct tep_event *event, struct tep_record *record,
> -			   struct list_head *jlist_head); /* optional */
> +			   void *private_ctx);/* optional */
>  };
>  
>  int cxl_parse_events(struct tracefs_instance *inst, struct event_ctx *ectx);