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Date:   Mon, 19 Dec 2022 13:21:02 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Zheng Yejian <zhengyejian1@huawei.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ross Zwisler <zwisler@google.com>,
        Tom Zanussi <zanussi@kernel.org>
Subject: Re: [PATCH] tracing: Add a way to filter function addresses to
 function names
Message-ID: <20221219132102.0dc6b7b9@gandalf.local.home>
In-Reply-To: <68fa6a9d-7a7f-00ba-e5a2-9b64f0aa7db3@huawei.com>
References: <20221214125209.09d736dd@gandalf.local.home>
        <68fa6a9d-7a7f-00ba-e5a2-9b64f0aa7db3@huawei.com>
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On Mon, 19 Dec 2022 10:38:50 +0800
Zheng Yejian <zhengyejian1@huawei.com> wrote:

> > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
> > index 33e0b4f8ebe6..db6e2f399440 100644
> > --- a/kernel/trace/trace_events.c
> > +++ b/kernel/trace/trace_events.c
> > @@ -2822,7 +2822,7 @@ static __init int setup_trace_triggers(char *str)
> >   		if (!trigger)
> >   			break;
> >   		bootup_triggers[i].event = strsep(&trigger, ".");
> > -		bootup_triggers[i].trigger = strsep(&trigger, ".");
> > +		bootup_triggers[i].trigger = strsep(&trigger, "");  
> 
> Would it be better to change to:
> 
>       bootup_triggers[i].trigger = trigger;
> 

Sure, I'll make the update.

> Because there is unnecessary loop if call strsep(s, "") :-)
>    strsep(s, ct) {
>      strpbrk(cs, ct) {
>        // when 'ct' is empty string, here will always return NULL
>        // after traversing string 'cs'

I'm not sure what you mean about an extra loop.

Thanks,

-- Steve