From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Evans Subject: Re: [PATCH 07/28] kvm tools: Move 'kvm__recommended_cpus' to arch-specific code Date: Wed, 07 Dec 2011 17:17:24 +1100 Message-ID: <4EDF04F4.40805@ozlabs.org> References: <4EDD8E73.8040505@ozlabs.org> <1323159616.3882.7.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, kvm-ppc@vger.kernel.org To: Sasha Levin Return-path: Received: from ozlabs.org ([203.10.76.45]:35031 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751054Ab1LGGQf (ORCPT ); Wed, 7 Dec 2011 01:16:35 -0500 In-Reply-To: <1323159616.3882.7.camel@lappy> Sender: kvm-owner@vger.kernel.org List-ID: On 06/12/11 19:20, Sasha Levin wrote: > Why is it getting moved out of generic code? > > This is used to determine the maximum amount of vcpus supported by the > host for a single guest, and as far as I know KVM_CAP_NR_VCPUS and > KVM_CAP_MAX_VCPUS are not arch specific. I checked api.txt and you're right, it isn't arch-specific. I assumed it was, because PPC KVM doesn't support it ;-) I've dropped this patch and in its place implemented the api.txt suggestion of "if KVM_CAP_NR_VCPUS fails, use 4" instead of die(); you'll see that when I repost. This will have the effect of PPC being limited to 4 CPUs until the kernel supports that CAP. (I'll see about this part too.) Thanks, Matt > > On Tue, 2011-12-06 at 14:39 +1100, Matt Evans wrote: >> Architectures can recommend/count/determine number of CPUs differently, so move >> this out of generic code. >> >> Signed-off-by: Matt Evans >> --- >> tools/kvm/kvm.c | 30 ------------------------------ >> tools/kvm/x86/kvm.c | 30 ++++++++++++++++++++++++++++++ >> 2 files changed, 30 insertions(+), 30 deletions(-) >> >> diff --git a/tools/kvm/kvm.c b/tools/kvm/kvm.c >> index 7ce1640..e526483 100644 >> --- a/tools/kvm/kvm.c >> +++ b/tools/kvm/kvm.c >> @@ -259,17 +259,6 @@ void kvm__register_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspac >> die_perror("KVM_SET_USER_MEMORY_REGION ioctl"); >> } >> >> -int kvm__recommended_cpus(struct kvm *kvm) >> -{ >> - int ret; >> - >> - ret = ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, KVM_CAP_NR_VCPUS); >> - if (ret <= 0) >> - die_perror("KVM_CAP_NR_VCPUS"); >> - >> - return ret; >> -} >> - >> static void kvm__pid(int fd, u32 type, u32 len, u8 *msg) >> { >> pid_t pid = getpid(); >> @@ -282,25 +271,6 @@ static void kvm__pid(int fd, u32 type, u32 len, u8 *msg) >> pr_warning("Failed sending PID"); >> } >> >> -/* >> - * The following hack should be removed once 'x86: Raise the hard >> - * VCPU count limit' makes it's way into the mainline. >> - */ >> -#ifndef KVM_CAP_MAX_VCPUS >> -#define KVM_CAP_MAX_VCPUS 66 >> -#endif >> - >> -int kvm__max_cpus(struct kvm *kvm) >> -{ >> - int ret; >> - >> - ret = ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, KVM_CAP_MAX_VCPUS); >> - if (ret <= 0) >> - ret = kvm__recommended_cpus(kvm); >> - >> - return ret; >> -} >> - >> struct kvm *kvm__init(const char *kvm_dev, u64 ram_size, const char *name) >> { >> struct kvm *kvm; >> diff --git a/tools/kvm/x86/kvm.c b/tools/kvm/x86/kvm.c >> index ac6c91e..75e4a52 100644 >> --- a/tools/kvm/x86/kvm.c >> +++ b/tools/kvm/x86/kvm.c >> @@ -76,6 +76,36 @@ bool kvm__arch_cpu_supports_vm(void) >> return regs.ecx & (1 << feature); >> } >> >> +int kvm__recommended_cpus(struct kvm *kvm) >> +{ >> + int ret; >> + >> + ret = ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, KVM_CAP_NR_VCPUS); >> + if (ret <= 0) >> + die_perror("KVM_CAP_NR_VCPUS"); >> + >> + return ret; >> +} >> + >> +/* >> + * The following hack should be removed once 'x86: Raise the hard >> + * VCPU count limit' makes it's way into the mainline. >> + */ >> +#ifndef KVM_CAP_MAX_VCPUS >> +#define KVM_CAP_MAX_VCPUS 66 >> +#endif >> + >> +int kvm__max_cpus(struct kvm *kvm) >> +{ >> + int ret; >> + >> + ret = ioctl(kvm->sys_fd, KVM_CHECK_EXTENSION, KVM_CAP_MAX_VCPUS); >> + if (ret <= 0) >> + ret = kvm__recommended_cpus(kvm); >> + >> + return ret; >> +} >> + >> /* >> * Allocating RAM size bigger than 4GB requires us to leave a gap >> * in the RAM which is used for PCI MMIO, hotplug, and unconfigured >> -- >> To unsubscribe from this list: send the line "unsubscribe kvm" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >