From owner-freebsd-current@FreeBSD.ORG Wed May 28 17:51:30 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 6B09E7DE; Wed, 28 May 2014 17:51:30 +0000 (UTC) Received: from mail-qg0-x22b.google.com (mail-qg0-x22b.google.com [IPv6:2607:f8b0:400d:c04::22b]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id ED1C621CC; Wed, 28 May 2014 17:51:29 +0000 (UTC) Received: by mail-qg0-f43.google.com with SMTP id 63so18742642qgz.2 for ; Wed, 28 May 2014 10:51:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=JPjUjsQ302MJbKEzVOibMBxFDbO/qs0B9iJPbR1rHp4=; b=qwgHLODcA1a0pl3VUqnJMpFxiM4tCIBLX9DGkjVNrEA/FS7F3v+vq4uqag6/3MD5ti 6O7chmDAGnquJ69k3qirgTXMl+ZX2rSVFiMQDwOM13+56ONlasBON7/4fpaK8hu2Lm+m ueW0JhEMhs1/lFw2rnlx38O6mQr9fDKcxZFXVMUlwvEjwErF6j9MUVf8qNAyCCyKUPVD TLGLcOnjWYUtLav5lE47fE7NWdnNRd+D/uY9g06BI0Jn0M3glLcFDyf0dgIsOrzQcAhq wbgzl7E/RSB3LTjaITerc+6oOHIy/C4p/KCoIutyTAOW5DmvXRlAwa+noWkKUxbxsSLI tCvQ== MIME-Version: 1.0 X-Received: by 10.140.104.195 with SMTP id a61mr1627273qgf.102.1401299489019; Wed, 28 May 2014 10:51:29 -0700 (PDT) Sender: adrian.chadd@gmail.com Received: by 10.224.191.201 with HTTP; Wed, 28 May 2014 10:51:28 -0700 (PDT) In-Reply-To: <201405280956.27800.jhb@freebsd.org> References: <20140524014713.GF13462@carrick-users.bishnet.net> <20140524103835.GI13462@carrick-users.bishnet.net> <201405280956.27800.jhb@freebsd.org> Date: Wed, 28 May 2014 10:51:28 -0700 X-Google-Sender-Auth: UjivDH4-yXqpqNDGBv4wQTX81z0 Message-ID: Subject: Re: Processor cores not properly detected/activated? From: Adrian Chadd To: John Baldwin Content-Type: text/plain; charset=UTF-8 Cc: Attilio Rao , freebsd-current , Jia-Shiun Li , Alan Somers , Tim Bishop X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 May 2014 17:51:30 -0000 On 28 May 2014 06:56, John Baldwin wrote: > Userland cpusets only default to 128 (CPU_MAXSIZE in ). > Changing MAXCPU to even 128 is unfortunately a potential KBI change since it > changes the size of 'cpuset_t'. We can certainly bump these in HEAD for 11, > but we might not be able to MFC them without introducing ABI breakage. > (The cpuset APIs do allow the size of cpuset_t to change as the size is > encoded in the API calls, so there is that, it's more that if some public > structure embeds a cpuset_t in the kernel that we would have problems. I > thought 'struct pcpu' did, but it does not.) > > Hmm, smp_rendezvous() accepts a cpuset_t as its first argument (and is a > public symbol used by kernel modules such as dtrace). 'struct rmlock' also > embeds a cpuset_t. So, I think we can't bump cpuset_t without breaking > the KBI. We can bump it in HEAD however. (Note, if re@ signed off, we could > perhaps merge to 10, but we tend to be very hesitant about breaking the KBI.) > One thing we could do safely is bump the userland cpuset size to 256 in 10. > It's really only MAXCPU that is problematic. > > In particular, I propose we bump the userland cpuset_t size to 256 now (and > go ahead and merge that to 10). In HEAD only we can bump MAXCPU for amd64 > to 256. Since 11 is going to be around for a few years, can we experiment bumping it up to something compute-cluster-computer-sized just to get it over with? Something stupid, like 4096 or something? -a