Re: [PATCH] Documentation: tracing: update format of sched_wakeup in example

[Steven Rostedt]

On Thu, 14 Mar 2024 15:41:36 +0100
Ali Zahraee <ahzahraee@xxxxxxxxx> wrote:

> The format of the sched_wakeup event is used as an example in the
> documentation. But the given format is obsolete. This patch updates the
> format in the example to match the current format of this event.
> 
> Signed-off-by: Ali Zahraee <ahzahraee@xxxxxxxxx>
> ---
>  Documentation/trace/events.rst | 25 +++++++++++++------------
>  1 file changed, 13 insertions(+), 12 deletions(-)
> 
> diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst
> index 759907c20e75..65fe205c95e6 100644
> --- a/Documentation/trace/events.rst
> +++ b/Documentation/trace/events.rst
> @@ -129,24 +129,25 @@ event::
>  	# cat /sys/kernel/tracing/events/sched/sched_wakeup/format
>  
>  	name: sched_wakeup
> -	ID: 60
> +	ID: 70

Really don't need to change that, as it's defined at compile time and may
be different. For example, I have:

 system: sched
 name: sched_wakeup
 ID: 297


>  	format:
>  		field:unsigned short common_type;	offset:0;	size:2;
> +                	signed:0;

Don't line break the fields, as new lines are part of the format.


>  		field:unsigned char common_flags;	offset:2;	size:1;
> -		field:unsigned char common_preempt_count;	offset:3;	size:1;
> -		field:int common_pid;	offset:4;	size:4;
> -		field:int common_tgid;	offset:8;	size:4;
> +                	signed:0;
> +		field:unsigned char common_preempt_count;	offset:3;
> +                	size:1; signed:0;

Again, the above needs to be on one line.

Thanks,

-- Steve

> +		field:int common_pid;	offset:4;	size:4;	signed:1;
>  
> -		field:char comm[TASK_COMM_LEN];	offset:12;	size:16;
> -		field:pid_t pid;	offset:28;	size:4;
> -		field:int prio;	offset:32;	size:4;
> -		field:int success;	offset:36;	size:4;
> -		field:int cpu;	offset:40;	size:4;
> +		field:char comm[16];	offset:8;	size:16;	signed:0;
> +		field:pid_t pid;	offset:24;	size:4;	signed:1;
> +		field:int prio;	offset:28;	size:4;	signed:1;
> +		field:int target_cpu;	offset:32;	size:4;	signed:1;
>  
> -	print fmt: "task %s:%d [%d] success=%d [%03d]", REC->comm, REC->pid,
> -		   REC->prio, REC->success, REC->cpu
> +	print fmt: "comm=%s pid=%d prio=%d target_cpu=%03d", REC->comm, REC->pid,
> +        	        REC->prio, REC->target_cpu
>  
> -This event contains 10 fields, the first 5 common and the remaining 5
> +This event contains 8 fields, the first 4 common and the remaining 4
>  event-specific.  All the fields for this event are numeric, except for
>  'comm' which is a string, a distinction important for event filtering.
>