From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH v3 0/6] powerpc: queued spinlocks and rwlocks Date: Wed, 8 Jul 2020 10:41:06 +0200 Message-ID: <20200708084106.GE597537@hirez.programming.kicks-ass.net> References: <20200706043540.1563616-1-npiggin@gmail.com> <24f75d2c-60cd-2766-4aab-1a3b1c80646e@redhat.com> <1594101082.hfq9x5yact.astroid@bobo.none> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1594101082.hfq9x5yact.astroid@bobo.none> Sender: kvm-ppc-owner@vger.kernel.org To: Nicholas Piggin Cc: linuxppc-dev@lists.ozlabs.org, Waiman Long , Anton Blanchard , Boqun Feng , kvm-ppc@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar , virtualization@lists.linux-foundation.org, Will Deacon List-Id: virtualization@lists.linuxfoundation.org On Tue, Jul 07, 2020 at 03:57:06PM +1000, Nicholas Piggin wrote: > Yes, powerpc could certainly get more performance out of the slow > paths, and then there are a few parameters to tune. Can you clarify? The slow path is already in use on ARM64 which is weak, so I doubt there's superfluous serialization present. And Will spend a fair amount of time on making that thing guarantee forward progressm, so there just isn't too much room to play. > We don't have a good alternate patching for function calls yet, but > that would be something to do for native vs pv. Going by your jump_label implementation, support for static_call should be fairly straight forward too, no? https://lkml.kernel.org/r/20200624153024.794671356@infradead.org