From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH 0/2] ARM: omap2+: omap_hwmod: Fix false lockdep warning Date: Fri, 6 Feb 2015 19:32:05 +0100 Message-ID: <20150206183205.GS21418@twins.programming.kicks-ass.net> References: <1423226916-18804-1-git-send-email-peter.ujfalusi@ti.com> <20150206141346.GP21418@twins.programming.kicks-ass.net> <54D4E64C.7060208@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <54D4E64C.7060208@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: Peter Ujfalusi Cc: Tony Lindgren , paul@pwsan.com, linux-omap@vger.kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org, balbi@ti.com, linux-arm-kernel@lists.infradead.org List-Id: linux-omap@vger.kernel.org On Fri, Feb 06, 2015 at 06:05:32PM +0200, Peter Ujfalusi wrote: > Certainly looks much simpler, but it adds quite a bit of data to the > omap_hwmod struct, and we have a _lot_ of them for omap2plus configuration. > > ls -al vmlinux > > w/o any the lockdep warning fixes: > 110109168 > > With my series applied: > 110112031 (base + 2863) > > With setting individual lockdep class: > 110114275 (base + 5107) > > I certainly like the lockdep_set_class() way since it is cleaner, but it adds > almost double amount of bytes to the kernel. Yeah, I've never really bothered with data too much, its a debug feature. So lock_class_key is 8 bytes, and strictly speaking you could union them over other fields, all we really need is unique addresses, we don't actually use the storage. From mboxrd@z Thu Jan 1 00:00:00 1970 From: peterz@infradead.org (Peter Zijlstra) Date: Fri, 6 Feb 2015 19:32:05 +0100 Subject: [PATCH 0/2] ARM: omap2+: omap_hwmod: Fix false lockdep warning In-Reply-To: <54D4E64C.7060208@ti.com> References: <1423226916-18804-1-git-send-email-peter.ujfalusi@ti.com> <20150206141346.GP21418@twins.programming.kicks-ass.net> <54D4E64C.7060208@ti.com> Message-ID: <20150206183205.GS21418@twins.programming.kicks-ass.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Feb 06, 2015 at 06:05:32PM +0200, Peter Ujfalusi wrote: > Certainly looks much simpler, but it adds quite a bit of data to the > omap_hwmod struct, and we have a _lot_ of them for omap2plus configuration. > > ls -al vmlinux > > w/o any the lockdep warning fixes: > 110109168 > > With my series applied: > 110112031 (base + 2863) > > With setting individual lockdep class: > 110114275 (base + 5107) > > I certainly like the lockdep_set_class() way since it is cleaner, but it adds > almost double amount of bytes to the kernel. Yeah, I've never really bothered with data too much, its a debug feature. So lock_class_key is 8 bytes, and strictly speaking you could union them over other fields, all we really need is unique addresses, we don't actually use the storage.