From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luc Van Oostenryck Subject: Re: [PATCH v15 00/13] mux controller abstraction and iio/i2c muxes Date: Sat, 3 Jun 2017 20:37:21 +0200 Message-ID: References: <1494791476-14599-1-git-send-email-peda@lysator.liu.se> <20170603102627.GA24274@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20170603102627.GA24274@kroah.com> Sender: linux-doc-owner@vger.kernel.org To: Greg Kroah-Hartman Cc: Peter Rosin , open list , Peter Rosin , Wolfram Sang , Rob Herring , Mark Rutland , Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Jonathan Corbet , linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-iio@vger.kernel.org, linux-doc@vger.kernel.org, Andrew Morton , Colin Ian King , Paul Gortmaker , Philipp Zabel , kernel@pengutronix.de List-Id: linux-i2c@vger.kernel.org On Sat, Jun 3, 2017 at 12:26 PM, Greg Kroah-Hartman wrote: > On Sun, May 14, 2017 at 09:51:03PM +0200, Peter Rosin wrote: >> From: Peter Rosin >> >> Hi Greg, >> >> Philipp found problems in v14 with using a mutex for locking that was >> the outcome of the review for v13, so I'm now using a semaphore instead >> of the rwsem that was in v13. That at least got rid of the scary call >> to downgrade_write. However, I'm still unsure about what you actually >> meant with your comment about lack of sparse markings [1]. I did add >> __must_check to the funcs that selects the mux, but I've got this >> feeling that this is not what you meant? > > I thought there was a way to mark a function as requiring a lock be held > when it is being called. Does sparse not support that anymore? sparse still support these annotations, of course. In this case, I suppose you're talking about '__must_hold()' which *must* be used instead of a pair of '__releases()' + '__acquires()' when the lock is help on function entry and exit. Cheers, -- Luc Van Oostenryck