From owner-svn-src-all@FreeBSD.ORG Thu Nov 4 08:51:45 2010 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 75932106566C; Thu, 4 Nov 2010 08:51:45 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 57F8B8FC18; Thu, 4 Nov 2010 08:51:45 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id oA48pjF1049603; Thu, 4 Nov 2010 08:51:45 GMT (envelope-from avg@svn.freebsd.org) Received: (from avg@localhost) by svn.freebsd.org (8.14.3/8.14.3/Submit) id oA48pj96049600; Thu, 4 Nov 2010 08:51:45 GMT (envelope-from avg@svn.freebsd.org) Message-Id: <201011040851.oA48pj96049600@svn.freebsd.org> From: Andriy Gapon Date: Thu, 4 Nov 2010 08:51:45 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r214774 - in head/sys: amd64/amd64 i386/i386 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Nov 2010 08:51:45 -0000 Author: avg Date: Thu Nov 4 08:51:45 2010 New Revision: 214774 URL: http://svn.freebsd.org/changeset/base/214774 Log: x86 topo_probe: do not probe smp topology if only one cpu is visible This could lead to a division by zero if hardware is multi-core and/or multi-threaded, but for some (quite unusual) reason FreeBSD sees only one logical processor. This could happen, for example, if neither MADT nor MP Table are presented by BIOS. Also: - assert in topo_probe_0x4 that BSP is accounted for - neither cpu_cores nor cpu_logical should be zero after successful probing, so either being zero is an indication of failed probing Reported by: vwe, Dan Allen Tested by: Dan Allen MFC after: 3 days Modified: head/sys/amd64/amd64/mp_machdep.c head/sys/i386/i386/mp_machdep.c Modified: head/sys/amd64/amd64/mp_machdep.c ============================================================================== --- head/sys/amd64/amd64/mp_machdep.c Thu Nov 4 07:53:09 2010 (r214773) +++ head/sys/amd64/amd64/mp_machdep.c Thu Nov 4 08:51:45 2010 (r214774) @@ -239,6 +239,9 @@ topo_probe_0x4(void) cpu_logical++; } + KASSERT(cpu_cores >= 1 && cpu_logical >= 1, + ("topo_probe_0x4 couldn't find BSP")); + cpu_cores /= cpu_logical; hyperthreading_cpus = cpu_logical; } @@ -310,7 +313,9 @@ topo_probe(void) return; logical_cpus_mask = 0; - if (cpu_vendor_id == CPU_VENDOR_AMD) + if (mp_ncpus <= 1) + cpu_cores = cpu_logical = 1; + else if (cpu_vendor_id == CPU_VENDOR_AMD) topo_probe_amd(); else if (cpu_vendor_id == CPU_VENDOR_INTEL) { /* @@ -332,10 +337,8 @@ topo_probe(void) * Fallback: assume each logical CPU is in separate * physical package. That is, no multi-core, no SMT. */ - if (cpu_cores == 0) - cpu_cores = 1; - if (cpu_logical == 0) - cpu_logical = 1; + if (cpu_cores == 0 || cpu_logical == 0) + cpu_cores = cpu_logical = 1; cpu_topo_probed = 1; } Modified: head/sys/i386/i386/mp_machdep.c ============================================================================== --- head/sys/i386/i386/mp_machdep.c Thu Nov 4 07:53:09 2010 (r214773) +++ head/sys/i386/i386/mp_machdep.c Thu Nov 4 08:51:45 2010 (r214774) @@ -286,6 +286,9 @@ topo_probe_0x4(void) cpu_logical++; } + KASSERT(cpu_cores >= 1 && cpu_logical >= 1, + ("topo_probe_0x4 couldn't find BSP")); + cpu_cores /= cpu_logical; hyperthreading_cpus = cpu_logical; } @@ -357,7 +360,9 @@ topo_probe(void) return; logical_cpus_mask = 0; - if (cpu_vendor_id == CPU_VENDOR_AMD) + if (mp_ncpus <= 1) + cpu_cores = cpu_logical = 1; + else if (cpu_vendor_id == CPU_VENDOR_AMD) topo_probe_amd(); else if (cpu_vendor_id == CPU_VENDOR_INTEL) { /* @@ -379,10 +384,8 @@ topo_probe(void) * Fallback: assume each logical CPU is in separate * physical package. That is, no multi-core, no SMT. */ - if (cpu_cores == 0) - cpu_cores = 1; - if (cpu_logical == 0) - cpu_logical = 1; + if (cpu_cores == 0 || cpu_logical == 0) + cpu_cores = cpu_logical = 1; cpu_topo_probed = 1; }