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[209.132.180.67]) by mx.google.com with ESMTP id u192si8358633pgc.218.2018.04.07.02.11.27; Sat, 07 Apr 2018 02:12:18 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@infradead.org header.s=merlin.20170209 header.b=Q28GBvVi; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751308AbeDGJIJ (ORCPT + 99 others); Sat, 7 Apr 2018 05:08:09 -0400 Received: from merlin.infradead.org ([205.233.59.134]:42620 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751069AbeDGJII (ORCPT ); Sat, 7 Apr 2018 05:08:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=0LTgOlLEZ30qaEpaV8xTLFX37uMw1GIr+eeI+OrJlhg=; b=Q28GBvViF2NatczXOprDMEgX+ UnR1B9P73eA/5xk+jLlo00DROpoNcTM2mhyFy+H7rvu9VLohifXTyQaOh88KHPOEOm4nRwRs668Gs hRmltYrlaWEjtZ08oKr31htkR2Cijj5u2lketfFftXwYgK/Py9hFWs4fDU7LDjlKc5TH5RzEbwNs7 wxfvdPjYBKrrmQ2AfYR8A0x6JJgvNiJV+bm2h4X62GZbXf7WG4BdTaVQ5eCbLk9uerThBg3c+mqx+ 0ljXXHG4Ztj2TAlU8fPzxcG6L9NHCmYrgUTWGjj4ZfRdVTBDfiKaPYtciE+Awy0P1JIZt/mb3T81O 75kKq/LjQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1f4jpH-0004Bx-Km; Sat, 07 Apr 2018 09:07:59 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 580FB20298CF9; Sat, 7 Apr 2018 11:07:54 +0200 (CEST) Date: Sat, 7 Apr 2018 11:07:54 +0200 From: Peter Zijlstra To: Waiman Long Cc: Will Deacon , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, mingo@kernel.org, boqun.feng@gmail.com, paulmck@linux.vnet.ibm.com, catalin.marinas@arm.com Subject: Re: [PATCH 02/10] locking/qspinlock: Remove unbounded cmpxchg loop from locking slowpath Message-ID: <20180407090754.GP4082@hirez.programming.kicks-ass.net> References: <1522947547-24081-1-git-send-email-will.deacon@arm.com> <1522947547-24081-3-git-send-email-will.deacon@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 06, 2018 at 04:50:19PM -0400, Waiman Long wrote: > # of threads 4.16 kernel patched 4.16 kernel > ------------ ----------- ------------------- > 1 7,417 kop/s 7,408 kop/s > 2 5,755 kop/s 4,486 kop/s > 3 4,214 kop/s 4,169 kop/s > 4 4,396 kop/s 4,383 kop/s > Interesting, I didn't see that dip in my userspace tests.. I'll have to try again.