Re: [PATCH] trace:cma: remove unnecessary event class cma_alloc_class

[Steven Rostedt]

On Thu, 23 Mar 2023 19:41:36 +0800
Wenchao Hao <haowenchao2@xxxxxxxxxx> wrote:

> After commit cb6c33d4dc09 ("cma: tracing: print alloc result in
> trace_cma_alloc_finish"), cma_alloc_class has only one event which is
> cma_alloc_busy_retry. So we can remove the cma_alloc_class.
> 

This is fine for an aesthetic view, but it has no functional change.
TRACE_EVENT() is simply defined as:

#define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
	DECLARE_EVENT_CLASS(name,			       \
			     PARAMS(proto),		       \
			     PARAMS(args),		       \
			     PARAMS(tstruct),		       \
			     PARAMS(assign),		       \
			     PARAMS(print));		       \
	DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args));

 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/trace/trace_events.h#n29

This patch simply un-open-codes it.

Acked-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>

Cheers,

-- Steve


> Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx>
> ---
>  include/trace/events/cma.h | 58 ++++++++++++++++----------------------
>  1 file changed, 25 insertions(+), 33 deletions(-)
> 
> diff --git a/include/trace/events/cma.h b/include/trace/events/cma.h
> index ef75ea606ab2..25103e67737c 100644
> --- a/include/trace/events/cma.h
> +++ b/include/trace/events/cma.h
> @@ -8,37 +8,6 @@
>  #include <linux/types.h>
>  #include <linux/tracepoint.h>
>  
> -DECLARE_EVENT_CLASS(cma_alloc_class,
> -
> -	TP_PROTO(const char *name, unsigned long pfn, const struct page *page,
> -		 unsigned long count, unsigned int align),
> -
> -	TP_ARGS(name, pfn, page, count, align),
> -
> -	TP_STRUCT__entry(
> -		__string(name, name)
> -		__field(unsigned long, pfn)
> -		__field(const struct page *, page)
> -		__field(unsigned long, count)
> -		__field(unsigned int, align)
> -	),
> -
> -	TP_fast_assign(
> -		__assign_str(name, name);
> -		__entry->pfn = pfn;
> -		__entry->page = page;
> -		__entry->count = count;
> -		__entry->align = align;
> -	),
> -
> -	TP_printk("name=%s pfn=0x%lx page=%p count=%lu align=%u",
> -		  __get_str(name),
> -		  __entry->pfn,
> -		  __entry->page,
> -		  __entry->count,
> -		  __entry->align)
> -);
> -
>  TRACE_EVENT(cma_release,
>  
>  	TP_PROTO(const char *name, unsigned long pfn, const struct page *page,
> @@ -125,12 +94,35 @@ TRACE_EVENT(cma_alloc_finish,
>  		  __entry->errorno)
>  );
>  
> -DEFINE_EVENT(cma_alloc_class, cma_alloc_busy_retry,
> +TRACE_EVENT(cma_alloc_busy_retry,
>  
>  	TP_PROTO(const char *name, unsigned long pfn, const struct page *page,
>  		 unsigned long count, unsigned int align),
>  
> -	TP_ARGS(name, pfn, page, count, align)
> +	TP_ARGS(name, pfn, page, count, align),
> +
> +	TP_STRUCT__entry(
> +		__string(name, name)
> +		__field(unsigned long, pfn)
> +		__field(const struct page *, page)
> +		__field(unsigned long, count)
> +		__field(unsigned int, align)
> +	),
> +
> +	TP_fast_assign(
> +		__assign_str(name, name);
> +		__entry->pfn = pfn;
> +		__entry->page = page;
> +		__entry->count = count;
> +		__entry->align = align;
> +	),
> +
> +	TP_printk("name=%s pfn=0x%lx page=%p count=%lu align=%u",
> +		  __get_str(name),
> +		  __entry->pfn,
> +		  __entry->page,
> +		  __entry->count,
> +		  __entry->align)
>  );
>  
>  #endif /* _TRACE_CMA_H */