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Date:   Wed, 19 Dec 2018 16:03:17 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Joe Perches <joe@perches.com>
Cc:     Tom Zanussi <zanussi@kernel.org>, tglx@linutronix.de,
        mhiramat@kernel.org, namhyung@kernel.org, vedang.patel@intel.com,
        bigeasy@linutronix.de, joel@joelfernandes.org,
        mathieu.desnoyers@efficios.com, julia@ni.com,
        linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org
Subject: Re: [PATCH 2/7] tracing: Change strlen to sizeof for hist trigger
 static strings
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On Wed, 19 Dec 2018 12:51:59 -0800
Joe Perches <joe@perches.com> wrote:


> > #define strncmp_prefix(str, prefix) \
> > 	strncmp(str, prefix, strlen(prefix))
> > 
> > in include/linux/string.h
> > 
> > And go around and use that throughout the kernel. By doing a quick
> > grep, I already spotted a few bugs.  
> 
> I hope you also convert the existing uses like
> 
> 	strncmp(str1, "str2", 4)
> 
> where the length value is precalculated to the strlen
> of the const string

Yeah sure.

> 
> But there seem to be _a lot_ of those...
> 
> $ git grep -P "\bstrncmp\s*\([^,]+,[^,]+,\s*\d+\s*\)" | wc -l
> 1681
> 

Right.

I'm going to first create the macro and probably just apply it to the
tracing directory. Then when the macro is added to the next merge
window, I'll post a bunch of patches that clean up the rest of the code.

-- Steve