Re: [PATCH 2/5] tracing: simplify the logic by defining next to be "lasst + 1"

From: Steven Rostedt
Date: Thu Jul 09 2020 - 17:59:23 EST


On Fri, 3 Jul 2020 10:06:09 +0800
Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> wrote:

> The value to be used and compared in trace_search_list() is "last + 1".
> Let's just define next to be "last + 1" instead of doing the addition
> each time.

Yeah, this is a nice clean up. I'll take this one.

-- Steve

>
> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
> ---
> kernel/trace/trace_output.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> index 47bf9f042b97..b704b3ef4264 100644
> --- a/kernel/trace/trace_output.c
> +++ b/kernel/trace/trace_output.c
> @@ -675,11 +675,11 @@ static LIST_HEAD(ftrace_event_list);
> static int trace_search_list(struct list_head **list)
> {
> struct trace_event *e;
> - int last = __TRACE_LAST_TYPE;
> + int next = __TRACE_LAST_TYPE + 1;
>
> if (list_empty(&ftrace_event_list)) {
> *list = &ftrace_event_list;
> - return last + 1;
> + return next;
> }
>
> /*
> @@ -687,17 +687,17 @@ static int trace_search_list(struct list_head **list)
> * lets see if somebody freed one.
> */
> list_for_each_entry(e, &ftrace_event_list, list) {
> - if (e->type != last + 1)
> + if (e->type != next)
> break;
> - last++;
> + next++;
> }
>
> /* Did we used up all 65 thousand events??? */
> - if ((last + 1) > TRACE_EVENT_TYPE_MAX)
> + if (next > TRACE_EVENT_TYPE_MAX)
> return 0;
>
> *list = &e->list;
> - return last + 1;
> + return next;
> }
>
> void trace_event_read_lock(void)