From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Mazur Subject: Re: [PATCH v3 8/7] pppoatm: fix missing wakeup in pppoatm_send() Date: Sun, 11 Nov 2012 17:12:19 +0100 Message-ID: <20121111161219.GA25360@shrek.podlesie.net> References: <1352240222-363-1-git-send-email-krzysiek@podlesie.net> <1352292734.7340.35.camel@shinybook.infradead.org> <20121110202338.GA1749@shrek.podlesie.net> <1352618933.9449.113.camel@shinybook.infradead.org> <20121111110437.GA25894@shrek.podlesie.net> <1352633993.9449.120.camel@shinybook.infradead.org> <20121111135002.GA32390@shrek.podlesie.net> <1352647601.9449.130.camel@shinybook.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Chas Williams - CONTRACTOR , davem@davemloft.net To: David Woodhouse Return-path: Content-Disposition: inline In-Reply-To: <1352647601.9449.130.camel@shinybook.infradead.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Sun, Nov 11, 2012 at 03:26:41PM +0000, David Woodhouse wrote: > On Sun, 2012-11-11 at 14:50 +0100, Krzysztof Mazur wrote: > > Looks and works ok after: > > + atmvcc->unlock_cb = pppoatm_unlock_cb; > > Heh, yeah. That would probably help :) > > Not sure if it's really necessary to optimise out the unneeded wakeups ??? > I don't think that code path gets exercised very hard for normal passing > of packets. Maybe only LCP echo and responses, on a live connection? > > But yeah, the locking *is* that simple, isn't it ??? and not the painful > stuff I had to do for the BLOCKED flag, which is why I deferred that > question to concentrate on the basic concept of using ->release_cb(). > > So it's silly *not* to do the 'need_wakeup'. But could it also live in > the 'blocked' word rather than expanding the structure further? Or just > *use* the BLOCKED bit, for that matter? > It would require using atomic ops because also pppoatm_pop() can modify this word. I think it's better to add additional word instead of using atomic ops. Krzysiek