From owner-svn-src-head@freebsd.org  Tue Mar 15 00:21:50 2016
Return-Path: <owner-svn-src-head@freebsd.org>
Delivered-To: svn-src-head@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 01A63AD16A2;
 Tue, 15 Mar 2016 00:21:50 +0000 (UTC)
 (envelope-from glebius@FreeBSD.org)
Received: from cell.glebi.us (glebi.us [96.95.210.25])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client CN "cell.glebi.us", Issuer "cell.glebi.us" (not verified))
 by mx1.freebsd.org (Postfix) with ESMTPS id E03F51D51;
 Tue, 15 Mar 2016 00:21:49 +0000 (UTC)
 (envelope-from glebius@FreeBSD.org)
Received: from cell.glebi.us (localhost [127.0.0.1])
 by cell.glebi.us (8.15.2/8.15.2) with ESMTPS id u2F0LmXD063273
 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO);
 Mon, 14 Mar 2016 17:21:49 -0700 (PDT)
 (envelope-from glebius@FreeBSD.org)
Received: (from glebius@localhost)
 by cell.glebi.us (8.15.2/8.15.2/Submit) id u2F0Lmwa063272;
 Mon, 14 Mar 2016 17:21:48 -0700 (PDT)
 (envelope-from glebius@FreeBSD.org)
X-Authentication-Warning: cell.glebi.us: glebius set sender to
 glebius@FreeBSD.org using -f
Date: Mon, 14 Mar 2016 17:21:48 -0700
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: Mateusz Guzik <mjguzik@gmail.com>
Cc: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: Re: svn commit: r296880 - in head: share/man/man9 sys/kern sys/sys
Message-ID: <20160315002148.GP1328@FreeBSD.org>
References: <201603150005.u2F050ps086390@repo.freebsd.org>
 <20160315001638.GA29505@dft-labs.eu>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20160315001638.GA29505@dft-labs.eu>
User-Agent: Mutt/1.5.24 (2015-08-30)
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.21
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 15 Mar 2016 00:21:50 -0000

On Tue, Mar 15, 2016 at 01:16:38AM +0100, Mateusz Guzik wrote:
M> On Tue, Mar 15, 2016 at 12:05:00AM +0000, Gleb Smirnoff wrote:
M> > +int
M> > +sysctl_handle_counter_u64_array(SYSCTL_HANDLER_ARGS)
M> > +{
M> > +	uint64_t *out;
M> > +	int error;
M> > +
M> > +	out = malloc(arg2 * sizeof(uint64_t), M_TEMP, M_WAITOK);
M> > +	for (int i = 0; i < arg2; i++)
M> > +		out[i] = counter_u64_fetch(((counter_u64_t *)arg1)[i]);
M> > +
M> > +	error = SYSCTL_OUT(req, out, arg2 * sizeof(uint64_t));
M> > +
M> > +	if (error || !req->newptr)
M> > +		return (error);
M> > +
M> > +	/*
M> > +	 * Any write attempt to a counter zeroes it.
M> > +	 */
M> > +	for (int i = 0; i < arg2; i++)
M> > +		counter_u64_zero(((counter_u64_t *)arg1)[i]);
M> > + 
M> > +	return (0);
M> > +}
M> > 
M> 
M> This never frees tha allocated buffer.
M> 
M> It would be better to just put stuff to userspace in a loop and avoid
M> allocations entirely. but does not look like there are no friendly
M> macros for that.

Thanks, Mateusz! Pointy hat is mine.

-- 
Totus tuus, Glebius.