Re: [PATCH V2] tracing: Revert "tracing: Remove pid in task_rename tracing output"

[Steven Rostedt <rostedt@goodmis.org>]

On Fri, 6 Mar 2026 15:59:54 +0800
Xuewen Yan <xuewen.yan@unisoc.com> wrote:

> This reverts commit e3f6a42272e028c46695acc83fc7d7c42f2750ad.
> 
> The commit says that the tracepoint only deals with the current task,
> however the following case is not current task:
> 
> comm_write() {
>     p = get_proc_task(inode);
>     if (!p)
>         return -ESRCH;
> 
>     if (same_thread_group(current, p))
>         set_task_comm(p, buffer);
> }
> where set_task_comm() calls __set_task_comm() which records
> the update of p and not current.
> 
> So revert the patch to show pid.
> 
> Fixes: e3f6a42272e0 ("tracing: Remove pid in task_rename tracing output")
> Reported-by: Guohua Yan <guohua.yan@unisoc.com>
> Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>

-- Steve

> ---
> v2:
> - update commit message (Steven)
> ---
>  include/trace/events/task.h | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/include/trace/events/task.h b/include/trace/events/task.h
> index 4f0759634306..b9a129eb54d9 100644
> --- a/include/trace/events/task.h
> +++ b/include/trace/events/task.h
> @@ -38,19 +38,22 @@ TRACE_EVENT(task_rename,
>  	TP_ARGS(task, comm),
>  
>  	TP_STRUCT__entry(
> +		__field(	pid_t,	pid)
>  		__array(	char, oldcomm,  TASK_COMM_LEN)
>  		__array(	char, newcomm,  TASK_COMM_LEN)
>  		__field(	short,	oom_score_adj)
>  	),
>  
>  	TP_fast_assign(
> +		__entry->pid = task->pid;
>  		memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
>  		strscpy(entry->newcomm, comm, TASK_COMM_LEN);
>  		__entry->oom_score_adj = task->signal->oom_score_adj;
>  	),
>  
> -	TP_printk("oldcomm=%s newcomm=%s oom_score_adj=%hd",
> -		  __entry->oldcomm, __entry->newcomm, __entry->oom_score_adj)
> +	TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%hd",
> +		__entry->pid, __entry->oldcomm,
> +		__entry->newcomm, __entry->oom_score_adj)
>  );
>  
>  /**