From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian McMenamin Date: Thu, 20 Mar 2008 22:52:27 +0000 Subject: Re: [PATCH] 1/2 Maple: Update bus driver to allow support of VMU Message-Id: <1206053547.6274.28.camel@localhost.localdomain> List-Id: References: <1205879413.6250.13.camel@localhost.localdomain> <1205880554.6250.25.camel@localhost.localdomain> <20080320135618.1a283b3e.akpm@linux-foundation.org> <1206051797.6274.17.camel@localhost.localdomain> <20080320153944.75b6edc1.akpm@linux-foundation.org> In-Reply-To: <20080320153944.75b6edc1.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Andrew Morton Cc: dwmw2@infradead.org, greg@kroah.com, lethal@linux-sh.org, linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org, linux-mtd@vger.kernel.org On Thu, 2008-03-20 at 15:39 -0700, Andrew Morton wrote: > On Thu, 20 Mar 2008 22:23:17 +0000 > Adrian McMenamin wrote: > > > > > > urgh, down_trylock(). And a secret, undocumented one too. > > > > > > A trylock is always an exceptional thing. How is *any* reader of this code > > > supposed to work out what the heck it's doing there? Convert it into > > > down(), run the code and decrypt the lockdep warnings, I suspect. > > > > > > > > > > > > Nope, I can't see any other lock being held when we call this function. > > > > > > The trylocks are an utter mystery to me. Please don't write mysterious > > > code. > > > > > > > OK, I am sure this is my problem but I have no idea why you are > > describing down_trylock as undocumented > > I'm describing your use of it! I'm sitting here trying to work out why on > earth this code is using the highly unusual (and highly suspicious) trylock > idiom and this is far from clear. > OK, I understand your point now. Some comments wouldn't go amiss, for sure.