Message-ID: <1512414756.6321.54.camel@perches.com>
Subject: Re: [PATCH tip/core/rcu 20/21] checkpatch: Add warnings for
 {smp_,}read_barrier_depends()
From: Joe Perches <joe@perches.com>
To: paulmck@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, jiangshanlai@gmail.com,
        dipankar@in.ibm.com, akpm@linux-foundation.org,
        mathieu.desnoyers@efficios.com, josh@joshtriplett.org,
        tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org,
        dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com,
        oleg@redhat.com, Andy Whitcroft <apw@canonical.com>
Date: Mon, 04 Dec 2017 11:12:36 -0800
In-Reply-To: <20171204190646.GD7829@linux.vnet.ibm.com>
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On Mon, 2017-12-04 at 11:06 -0800, Paul E. McKenney wrote:
> On Fri, Dec 01, 2017 at 08:45:13PM -0800, Joe Perches wrote:
> > On Fri, 2017-12-01 at 13:44 -0800, Paul E. McKenney wrote:
> 
> > If you really wanted to optimize, you could make the first (smp_|)
> > become (?:smp_|) to avoid the unused capture group.
> > Or perhaps this could emit the actual type in the message like:
> > 
> > 		if (!$file && $line =~ /\b((?:smp_|)read_barrier_depends)\s*\(/ {
> > 			WARN("READ_BARRIER_DEPENDS",
> > 			     "$1 should only be used in READ_ONCE or DEC Alpha code\n" . $herecurr);
> 
> How about like this?  (s/$1/$1read_barrier_depends/).

Works for me.

Acked-by: Joe Perches <joe@perches.com>

Are you going to merge this?
Normally akpm does checkpatch merging but whatever
works for you is OK by me.

cheers, Joe

> commit e4f1d781e33c150547c68e55099794b98ee14d5e
> Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> Date:   Mon Nov 27 09:37:35 2017 -0800
> {smp_,}read_barrier_depends()
>     
>     Now that both smp_read_barrier_depends() and read_barrier_depends()
>     are being de-emphasized, warn if any are added.
>     
>     Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
>     Cc: Andy Whitcroft <apw@canonical.com>
>     Cc: Joe Perches <joe@perches.com>
>     [ paulmck: Skipped checking files and handled whitespace per Joe Perches.
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 95cda3ecc66b..9a384bfe2bd5 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -5586,6 +5586,12 @@ sub process {
>  			}
>  		}
>  
> +# check for smp_read_barrier_depends and read_barrier_depends
> +		if (!$file && $line =~ /\b(smp_|)read_barrier_depends\s*\(/) {
> +			WARN("READ_BARRIER_DEPENDS",
> +			     "$1read_barrier_depends should only be used in READ_ONCE or DEC Alpha code\n" . $herecurr);
> +		}
> +
>  # check of hardware specific defines
>  		if ($line =~ m@^.\s*\#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@ && $realfile !~ m@include/asm-@) {
>  			CHK("ARCH_DEFINES",
>