When we changed build configure to: KERNELS="linux-2.6-xen0 linux-2.6-xenU" export KERNELS After reboot to this xen0, we found there is only one CPU in xen0. "uname -a" shows it''s a SMP but "cat /proc/cpuinfo" shows only one cpu. We see this issue on ChangeSet 10143 and 10151. If we build with the default configure, we can see all cpus in xen0. Bests Jeff _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Ryan Harper
2006-May-25 14:25 UTC
Re: [Xen-devel] only one CPU is detected when dom0 boots up
* Zheng, Jeff <jeff.zheng@intel.com> [2006-05-25 09:16]:> When we changed build configure to: > KERNELS="linux-2.6-xen0 linux-2.6-xenU" > export KERNELS > > After reboot to this xen0, we found there is only one CPU in xen0. > "uname -a" shows it''s a SMP but "cat /proc/cpuinfo" shows only one cpu. > > We see this issue on ChangeSet 10143 and 10151. > > If we build with the default configure, we can see all cpus in xen0.linux-defconfig_xen0_x86* does [1]not have CONFIG_SMP set, so unless you''ve manually changed the linux config, you won''t see more than one cpu. 1. % grep CONFIG_SMP buildconfigs/linux-defconfig_xen0_x86_* buildconfigs/linux-defconfig_xen0_x86_32:# CONFIG_SMP is not set buildconfigs/linux-defconfig_xen0_x86_64:# CONFIG_SMP is not set -- Ryan Harper Software Engineer; Linux Technology Center IBM Corp., Austin, Tx (512) 838-9253 T/L: 678-9253 ryanh@us.ibm.com _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Yu, Ping Y
2006-May-25 16:57 UTC
RE: [Xen-devel] only one CPU is detected when dom0 boots up
Harper, You are right! The default build configuration linux-defconfig_xen0_x86_64/ linux-defconfig_xen0_x86_32 is UP, and we have manually changed the default configure to make it SMP. We noticed that "uname -a" shows the dom0''s kernel is SMP, but the problem is that only one CPU is found when dom0 boots up. With the same change, we know at least change set 10033 is OK to boot with multiple CPUs. Ping>-----Original Message----- >From: xen-devel-bounces@lists.xensource.com >[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Ryan Harper >Sent: 2006年5月25日 7:25 >To: Zheng, Jeff >Cc: xen-devel@lists.xensource.com >Subject: Re: [Xen-devel] only one CPU is detected when dom0 boots up > >* Zheng, Jeff <jeff.zheng@intel.com> [2006-05-25 09:16]: >> When we changed build configure to: >> KERNELS="linux-2.6-xen0 linux-2.6-xenU" >> export KERNELS >> >> After reboot to this xen0, we found there is only one CPU in xen0. >> "uname -a" shows it''s a SMP but "cat /proc/cpuinfo" shows only one cpu. >> >> We see this issue on ChangeSet 10143 and 10151. >> >> If we build with the default configure, we can see all cpus in xen0. > >linux-defconfig_xen0_x86* does [1]not have CONFIG_SMP set, so unless >you''ve manually changed the linux config, you won''t see more than one >cpu. > >1. % grep CONFIG_SMP buildconfigs/linux-defconfig_xen0_x86_* >buildconfigs/linux-defconfig_xen0_x86_32:# CONFIG_SMP is not set >buildconfigs/linux-defconfig_xen0_x86_64:# CONFIG_SMP is not set > >-- >Ryan Harper >Software Engineer; Linux Technology Center >IBM Corp., Austin, Tx >(512) 838-9253 T/L: 678-9253 >ryanh@us.ibm.com > >_______________________________________________ >Xen-devel mailing list >Xen-devel@lists.xensource.com >http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Ryan Harper
2006-May-25 17:43 UTC
Re: [Xen-devel] only one CPU is detected when dom0 boots up
* Yu, Ping Y <ping.y.yu@intel.com> [2006-05-25 11:59]:> Harper, > > You are right! The default build configuration linux-defconfig_xen0_x86_64/ > linux-defconfig_xen0_x86_32 is UP, and we have manually changed the default > configure to make it SMP. We noticed that "uname -a" shows the dom0''s kernel is > SMP, but the problem is that only one CPU is found when dom0 boots up. > With the same change, we know at least change set 10033 is OK to boot with > multiple CPUs.Make sure CONFIG_HOTPLUG_CPU is also enabled. After having both CONFIG_SMP and CONFIG_HOTPLUG_CPU, try: xm vcpu-set 0 2 replacing 2 with however many cpu''s you think dom0 should have. -- Ryan Harper Software Engineer; Linux Technology Center IBM Corp., Austin, Tx (512) 838-9253 T/L: 678-9253 ryanh@us.ibm.com _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Yu, Ping Y
2006-May-25 23:00 UTC
RE: [Xen-devel] only one CPU is detected when dom0 boots up
Harper, Thanks a lot. It works! But the question remains that why change set 10033 could bring up multiple CPUs without hotplug. I notice that there is no change in build configuration since 9980. Ping>-----Original Message----- >From: Ryan Harper [mailto:ryanh@us.ibm.com] >Sent: 2006年5月25日 10:44 >To: Yu, Ping Y >Cc: Zheng, Jeff; xen-devel@lists.xensource.com >Subject: Re: [Xen-devel] only one CPU is detected when dom0 boots up > >* Yu, Ping Y <ping.y.yu@intel.com> [2006-05-25 11:59]: >> Harper, >> >> You are right! The default build configuration linux-defconfig_xen0_x86_64/ >> linux-defconfig_xen0_x86_32 is UP, and we have manually changed the default >> configure to make it SMP. We noticed that "uname -a" shows the dom0''s kernel >is >> SMP, but the problem is that only one CPU is found when dom0 boots up. >> With the same change, we know at least change set 10033 is OK to boot with >> multiple CPUs. > >Make sure CONFIG_HOTPLUG_CPU is also enabled. After having both >CONFIG_SMP and CONFIG_HOTPLUG_CPU, try: > >xm vcpu-set 0 2 > >replacing 2 with however many cpu''s you think dom0 should have. > >-- >Ryan Harper >Software Engineer; Linux Technology Center >IBM Corp., Austin, Tx >(512) 838-9253 T/L: 678-9253 >ryanh@us.ibm.com_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Yu, Ping Y
2006-May-25 23:22 UTC
RE: [Xen-devel] only one CPU is detected when dom0 boots up
I notice that it is caused by change set 10139, then does it mean that we have to configure CPU hot plug to start multiple CPUs in the future? Ping>-----Original Message----- >From: xen-devel-bounces@lists.xensource.com >[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of Yu, Ping Y >Sent: 2006年5月25日 16:01 >To: Ryan Harper >Cc: xen-devel@lists.xensource.com; Zheng, Jeff >Subject: RE: [Xen-devel] only one CPU is detected when dom0 boots up > >Harper, > >Thanks a lot. It works! But the question remains that why change set 10033 >could bring up multiple CPUs without hotplug. >I notice that there is no change in build configuration since 9980. > >Ping > >>-----Original Message----- >>From: Ryan Harper [mailto:ryanh@us.ibm.com] >>Sent: 2006年5月25日 10:44 >>To: Yu, Ping Y >>Cc: Zheng, Jeff; xen-devel@lists.xensource.com >>Subject: Re: [Xen-devel] only one CPU is detected when dom0 boots up >> >>* Yu, Ping Y <ping.y.yu@intel.com> [2006-05-25 11:59]: >>> Harper, >>> >>> You are right! The default build configuration linux-defconfig_xen0_x86_64/ >>> linux-defconfig_xen0_x86_32 is UP, and we have manually changed the default >>> configure to make it SMP. We noticed that "uname -a" shows the dom0''s kernel >>is >>> SMP, but the problem is that only one CPU is found when dom0 boots up. >>> With the same change, we know at least change set 10033 is OK to boot with >>> multiple CPUs. >> >>Make sure CONFIG_HOTPLUG_CPU is also enabled. After having both >>CONFIG_SMP and CONFIG_HOTPLUG_CPU, try: >> >>xm vcpu-set 0 2 >> >>replacing 2 with however many cpu''s you think dom0 should have. >> >>-- >>Ryan Harper >>Software Engineer; Linux Technology Center >>IBM Corp., Austin, Tx >>(512) 838-9253 T/L: 678-9253 >>ryanh@us.ibm.com > >_______________________________________________ >Xen-devel mailing list >Xen-devel@lists.xensource.com >http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2006-May-26 07:13 UTC
Re: [Xen-devel] only one CPU is detected when dom0 boots up
On 26 May 2006, at 00:22, Yu, Ping Y wrote:> I notice that it is caused by change set 10139, then does it mean that > we have > to configure CPU hot plug to start multiple CPUs in the future?It''s needed for domU''s. Dom0 can bring up SMP without hotplug infrastructure. -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel