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From c5616455a4db0e5b67a41e4f6ec12b939e95eaa1 Mon Sep 17 00:00:00 2001
From: Andrew Jones <drjones@redhat.com>
Date: Tue, 21 Jan 2014 10:46:52 +0100
Subject: globally limit the maximum number of CPUs

We now globally limit the number of VCPUs.
Especially, there is no way one can specify more than
max_cpus VCPUs for a VM.

This allows us the restore the ppc max_cpus limitation to the upstream
default and minimize the ppc hack in kvm-all.c.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
Signed-off-by: Danilo Cesar Lemes de Paula <ddepaula@redhat.com>

Rebase notes (2.11.0):
- Removed CONFIG_RHV reference
- Update commit log

Merged patches (2.11.0):
- 92fef14623 redhat: remove manual max_cpus limitations for ppc
- bb722e9eff redhat: globally limit the maximum number of CPUs
- fdeef3c1c7 RHEL: Set vcpus hard limit to 240 for Power
- 0584216921 Match POWER max cpus to x86

Signed-off-by: Andrew Jones <drjones@redhat.com>

Merged patches (5.1.0):
- redhat: globally limit the maximum number of CPUs
- redhat: remove manual max_cpus limitations for ppc
- use recommended max vcpu count

Merged patches (5.2.0 rc0):
- f8a4123 vl: Remove downstream-only MAX_RHEL_CPUS code

Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
 accel/kvm/kvm-all.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 0125c17edb..b5d488a027 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -2413,6 +2413,18 @@ static int kvm_init(MachineState *ms)
     soft_vcpus_limit = kvm_recommended_vcpus(s);
     hard_vcpus_limit = kvm_max_vcpus(s);
 
+#ifdef HOST_PPC64
+    /*
+     * On POWER, the kernel advertises a soft limit based on the
+     * number of CPU threads on the host.  We want to allow exceeding
+     * this for testing purposes, so we don't want to set hard limit
+     * to soft limit as on x86.
+     */
+#else
+    /* RHEL doesn't support nr_vcpus > soft_vcpus_limit */
+    hard_vcpus_limit = soft_vcpus_limit;
+#endif
+
     while (nc->name) {
         if (nc->num > soft_vcpus_limit) {
             warn_report("Number of %s cpus requested (%d) exceeds "
-- 
2.31.1