diff options
-rw-r--r-- | qemu-options.hx | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/qemu-options.hx b/qemu-options.hx index 14ff35dd4e..214c477dcc 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -207,14 +207,27 @@ DEF("smp", HAS_ARG, QEMU_OPTION_smp, QEMU_ARCH_ALL) SRST ``-smp [[cpus=]n][,maxcpus=maxcpus][,sockets=sockets][,dies=dies][,cores=cores][,threads=threads]`` - Simulate an SMP system with n CPUs. On the PC target, up to 255 CPUs - are supported. On Sparc32 target, Linux limits the number of usable - CPUs to 4. For the PC target, the number of cores per die, the - number of threads per cores, the number of dies per packages and the - total number of sockets can be specified. Missing values will be - computed. If any on the three values is given, the total number of - CPUs n can be omitted. maxcpus specifies the maximum number of - hotpluggable CPUs. + 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. + + To control reporting of CPU topology information, the number of sockets, + dies per socket, cores per die, and threads per core can be specified. + The sum `` sockets * cores * dies * threads `` must be equal to the + maximum CPU count. CPU targets may only support a subset of the topology + parameters. Where a CPU target does not support use of a particular + topology parameter, its value should be assumed to be 1 for the purpose + of computing the CPU maximum count. + + Either the initial CPU count, or at least one of the topology parameters + must be specified. Values for any omitted parameters will be computed + from those which are given. Historically preference was given to the + coarsest topology parameters when computing missing values (ie sockets + preferred over cores, which were preferred over threads), however, this + behaviour is considered liable to change. ERST DEF("numa", HAS_ARG, QEMU_OPTION_numa, |