Return-Path: MIME-Version: 1.0 In-Reply-To: References: <1335976922-19456-1-git-send-email-mathewm@codeaurora.org> <1335976922-19456-4-git-send-email-mathewm@codeaurora.org> Date: Fri, 4 May 2012 22:11:55 -0300 Message-ID: Subject: Re: [PATCH 3/4] Bluetooth: Lock the L2CAP channel when sending From: Ulisses Furquim To: Mat Martineau Cc: linux-bluetooth@vger.kernel.org, gustavo@padovan.org, marcel@holtmann.org, pkrystad@codeaurora.org, andrei.emeltchenko.news@gmail.com Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Mat, On Fri, May 4, 2012 at 6:54 PM, Mat Martineau wrote: > > Hi Ulisses - > > > On Fri, 4 May 2012, Ulisses Furquim wrote: > >> Hi Mat, >> >> On Wed, May 2, 2012 at 1:42 PM, Mat Martineau >> wrote: >>> >>> The ERTM and streaming mode transmit queue must only be accessed while >>> the L2CAP channel lock is held. ?Locking the channel before calling >>> l2cap_chan_send ensures that multiple threads cannot simultaneously >>> manipulate the queue when sending and receiving concurrently. >>> >>> L2CAP channel locking had previously moved to the l2cap_chan struct >>> instead of the associated socket, so some of the old socket locking >>> can also be removed in this patch. >>> >>> Signed-off-by: Mat Martineau >>> --- >>> ?include/net/bluetooth/bluetooth.h | ? ?2 -- >>> ?net/bluetooth/l2cap_sock.c ? ? ? ?| ? 15 ++++++++------- >>> ?2 files changed, 8 insertions(+), 9 deletions(-) >> >> >> Looks good. I'm just wondering if we still have issues with chan lock >> versus sock lock elsewhere. Maybe you've done some auditing of this? > > I did an extensive review of the locking code with respect to ERTM last > week, and I'm satisfied with the use of chan_lock there. > > The work to decouple l2cap_chan from sockets is not yet complete, so there > are still socket locking calls at connect and disconnect time. The data path > looks like it is clear of socket locks now. Thanks, that's good to know. Regards, -- Ulisses Furquim ProFUSION embedded systems http://profusion.mobi Mobile: +55 19 9250 0942 Skype: ulissesffs