From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Date: Fri, 01 Apr 2016 23:05:40 +0000 Subject: Re: [PATCH v3 09/11] i2c: rcar: revoke START request early Message-Id: <56FEFEC4.6010401@cogentembedded.com> List-Id: References: <1447948611-2615-1-git-send-email-wsa@the-dreams.de> <1447948611-2615-10-git-send-email-wsa@the-dreams.de> <56FD9080.4090203@cogentembedded.com> <20160331224838.GA7381@katana> <56FED245.4010503@cogentembedded.com> <20160401201415.GA25936@katana> In-Reply-To: <20160401201415.GA25936@katana> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Wolfram Sang Cc: linux-i2c@vger.kernel.org, linux-sh@vger.kernel.org, Magnus Damm , Simon Horman , Laurent Pinchart , Geert Uytterhoeven , Kuninori Morimoto , Yoshihiro Shimoda , "stable@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" On 04/01/2016 11:14 PM, Wolfram Sang wrote: > >>> IIRC my tests showed that if you don't remove >>> the spinlocks (patch 4), the interrupt latency will already be too high >>> again. >> >> Thank you for the valuable info! > > Oh, and add patch 6 to it. The context switches are a major problem in > this. Thanks again! I ended up backporting all the patches up to #9. Not sure it'd be acceptable for the -stable kernels since there's a lot of refactors involved... MBR, Sergei