diff options
| author | Yanan Wang <wangyanan55@huawei.com> | 2021-09-29 10:58:05 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-10-01 15:27:56 +0200 |
| commit | 7d8c5a39628820f6927b8b70c8f54872f5d1a196 (patch) | |
| tree | 0e2713d9bb3fc3c2e49f852c52c039aed0b7819c /qemu-options.hx | |
| parent | 9a52b508061163df4dae05e708cd2a9cd790ad04 (diff) | |
machine: Set the value of cpus to match maxcpus if it's omitted
Currently we directly calculate the omitted cpus based on the given
incomplete collection of parameters. This makes some cmdlines like:
-smp maxcpus=16
-smp sockets=2,maxcpus=16
-smp sockets=2,dies=2,maxcpus=16
-smp sockets=2,cores=4,maxcpus=16
not work. We should probably set the value of cpus to match maxcpus
if it's omitted, which will make above configs start to work.
So the calculation logic of cpus/maxcpus after this patch will be:
When both maxcpus and cpus are omitted, maxcpus will be calculated
from the given parameters and cpus will be set equal to maxcpus.
When only one of maxcpus and cpus is given then the omitted one
will be set to its counterpart's value. Both maxcpus and cpus may
be specified, but maxcpus must be equal to or greater than cpus.
Note: change in this patch won't affect any existing working cmdlines
but allows more incomplete configs to be valid.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-6-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'qemu-options.hx')
| -rw-r--r-- | qemu-options.hx | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/qemu-options.hx b/qemu-options.hx index 4a092a092a..2eac830fdb 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -220,9 +220,14 @@ SRST Simulate a SMP system with '\ ``n``\ ' CPUs initially present on the machine type board. On boards supporting CPU hotplug, the optional '\ ``maxcpus``\ ' parameter can be set to enable further CPUs to be - added at runtime. If omitted the maximum number of CPUs will be - set to match the initial CPU count. Both parameters are subject to - an upper limit that is determined by the specific machine type chosen. + added at runtime. When both parameters are omitted, the maximum number + of CPUs will be calculated from the provided topology members and the + initial CPU count will match the maximum number. When only one of them + is given then the omitted one will be set to its counterpart's value. + Both parameters may be specified, but the maximum number of CPUs must + be equal to or greater than the initial CPU count. Both parameters are + subject to an upper limit that is determined by the specific machine + type chosen. To control reporting of CPU topology information, the number of sockets, dies per socket, cores per die, and threads per core can be specified. |