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| author | Mukesh Rathor <mukesh.rathor@oracle.com> | 2010-07-19 10:25:08 -0700 |
|---|---|---|
| committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2010-08-04 14:47:30 -0700 |
| commit | c06ee78d73fd24e8d8a65f16380f6a0551107e1b (patch) | |
| tree | ec5b936b4c1661cff9fd3b5ad8463e86d176a734 /arch/x86/xen/enlighten.c | |
| parent | 8a22b9996b001c88f2bfb54c6de6a05fc39e177a (diff) | |
| download | linux-c06ee78d73fd24e8d8a65f16380f6a0551107e1b.tar.gz linux-c06ee78d73fd24e8d8a65f16380f6a0551107e1b.tar.bz2 linux-c06ee78d73fd24e8d8a65f16380f6a0551107e1b.zip | |
xen: support large numbers of CPUs with vcpu info placement
When vcpu info placement is supported, we're not limited to MAX_VIRT_CPUS
vcpus. However, if it isn't supported, then ignore any excess vcpus.
Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Diffstat (limited to 'arch/x86/xen/enlighten.c')
| -rw-r--r-- | arch/x86/xen/enlighten.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index fef034a04c24..90a3e8026767 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -97,6 +97,14 @@ struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; */ static int have_vcpu_info_placement = 1; +static void clamp_max_cpus(void) +{ +#ifdef CONFIG_SMP + if (setup_max_cpus > MAX_VIRT_CPUS) + setup_max_cpus = MAX_VIRT_CPUS; +#endif +} + static void xen_vcpu_setup(int cpu) { struct vcpu_register_vcpu_info info; @@ -104,13 +112,17 @@ static void xen_vcpu_setup(int cpu) struct vcpu_info *vcpup; BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info); - per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; - if (!have_vcpu_info_placement) - return; /* already tested, not available */ + if (cpu < MAX_VIRT_CPUS) + per_cpu(xen_vcpu,cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; - vcpup = &per_cpu(xen_vcpu_info, cpu); + if (!have_vcpu_info_placement) { + if (cpu >= MAX_VIRT_CPUS) + clamp_max_cpus(); + return; + } + vcpup = &per_cpu(xen_vcpu_info, cpu); info.mfn = arbitrary_virt_to_mfn(vcpup); info.offset = offset_in_page(vcpup); @@ -125,6 +137,7 @@ static void xen_vcpu_setup(int cpu) if (err) { printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err); have_vcpu_info_placement = 0; + clamp_max_cpus(); } else { /* This cpu is using the registered vcpu info, even if later ones fail to. */ |