Return-Path: Date: Wed, 8 Jun 2011 23:16:48 -0300 From: "Gustavo F. Padovan" To: Mat Martineau Cc: linux-bluetooth@vger.kernel.org Subject: Re: [PATCH 3/4] Bluetooth: Limit depth of the HCI TX queue with ERTM mode Message-ID: <20110609021648.GA2776@joana> References: <1307143270-2655-1-git-send-email-mathewm@codeaurora.org> <1307143270-2655-3-git-send-email-mathewm@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1307143270-2655-3-git-send-email-mathewm@codeaurora.org> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Mat, * Mat Martineau [2011-06-03 16:21:09 -0700]: > In order to provide timely responses to REJ, SREJ, and poll input from > the remote device, it helps to reduce the number of ERTM data frames > in the HCI TX queue at one time. If a full TX window of data is in the > HCI TX queue, any responses to REJ, SREJ, or polls must wait in line > behind all previously queued data. This latency leads to disconnects, > and will be more severe with extended window sizes. I prefer if we go with a hci_send_acl_prio() implementation. It will have much less overhead using a workqueue. As it will be filled only by S-frames with a few bytes each I don't think we will have problems. So lets go with this approach and see what we can get. Gustavo