Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Wed, 16 Jan 2019 09:32:33 -0700
From:   Jonathan Corbet <corbet@lwn.net>
To:     Seeteena Thoufeek <s1seetee@linux.vnet.ibm.com>
Cc:     peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
        alexander.shishkin@linux.intel.com, jolsa@redhat.com,
        namhyung@kernel.org, linux-kernel@vger.kernel.org,
        ravi.bangoria@linux.ibm.com
Subject: Re: [PATCH] perf scripts python: Add Python 3 support to
 mem-phys-addr.py
Message-ID: <20190116093233.4873b784@lwn.net>
In-Reply-To: <1547655825-28754-8-git-send-email-s1seetee@linux.vnet.ibm.com>
References: <1547655825-28754-1-git-send-email-s1seetee@linux.vnet.ibm.com>
        <1547655825-28754-8-git-send-email-s1seetee@linux.vnet.ibm.com>
Organization: LWN.net
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, 16 Jan 2019 21:53:36 +0530
Seeteena Thoufeek <s1seetee@linux.vnet.ibm.com> wrote:

> Support both Python 2 and Python 3 in mem-phys-addr.py. ``print`` is now a
> function rather than a statement. This should have no functional change.
> 
> Fix lambda syntax error.

So, I just picked one of these at random....

> Signed-off-by: Seeteena Thoufeek <s1seetee@linux.vnet.ibm.com>
> Reviewed-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
> ---
>  tools/perf/scripts/python/mem-phys-addr.py | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/tools/perf/scripts/python/mem-phys-addr.py b/tools/perf/scripts/python/mem-phys-addr.py
> index ebee2c5..52fe9bd 100644
> --- a/tools/perf/scripts/python/mem-phys-addr.py
> +++ b/tools/perf/scripts/python/mem-phys-addr.py
> @@ -38,14 +38,14 @@ def parse_iomem():
>  			pmem.append(long(m[1], 16))
>  
>  def print_memory_type():
> -	print "Event: %s" % (event_name)
> -	print "%-40s  %10s  %10s\n" % ("Memory type", "count", "percentage"),
> -	print "%-40s  %10s  %10s\n" % ("----------------------------------------", \
> -					"-----------", "-----------"),
> +	print("Event: %s" % (event_name))
> +	print("%-40s  %10s  %10s\n" % ("Memory type", "count", "percentage")),
> +	print("%-40s  %10s  %10s\n" % ("----------------------------------------", \
> +					"-----------", "-----------")),

You have not added "from __future__ import print_function", so you're
relying on a Python 2 parsing oddity to make this work.  If anybody ever
adds a second parameter, things will break.  I think that if you really
want to support both versions (which seems like the right goal) you should
add the import and do it properly.

Thanks,

jon