We are currently using maxcpus to calculate the omitted sockets but using cpus to calculate the omitted cores/threads. This makes cmdlines like: -smp cpus=8,maxcpus=16 -smp cpus=8,cores=4,maxcpus=16 -smp cpus=8,threads=2,maxcpus=16 work fine but the ones like: -smp cpus=8,sockets=2,maxcpus=16 -smp cpus=8,sockets=2,cores=4,maxcpus=16 -smp cpus=8,sockets=2,threads=2,maxcpus=16 break the sanity check.
Since we require for a valid config that the product of "sockets * cores * threads" should equal to the maxcpus, we should uniformly use maxcpus to calculate their omitted values. Also the if-branch of "cpus == 0 || sockets == 0" was split into two branches of "cpus == 0" and "sockets == 0" so that we can clearly read that we are parsing the configuration with a preference on cpus over sockets over cores over threads. Note: change in this patch won't affect any existing working cmdlines but improves consistency and allows more incomplete configs to be valid. Signed-off-by: Yanan Wang <wangyana...@huawei.com> Reviewed-by: Andrew Jones <drjo...@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gu...@ionos.com> --- hw/core/machine.c | 30 +++++++++++++++--------------- hw/i386/pc.c | 30 +++++++++++++++--------------- 2 files changed, 30 insertions(+), 30 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index cf9cf53911..56bd3033a5 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -760,24 +760,26 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) } /* compute missing values, prefer sockets over cores over threads */ - if (cpus == 0 || sockets == 0) { + maxcpus = maxcpus > 0 ? maxcpus : cpus; + + if (cpus == 0) { + sockets = sockets > 0 ? sockets : 1; cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; - if (cpus == 0) { - sockets = sockets > 0 ? sockets : 1; - cpus = cores * threads * sockets; - } else { - maxcpus = maxcpus > 0 ? maxcpus : cpus; - sockets = maxcpus / (cores * threads); - } + cpus = sockets * cores * threads; + maxcpus = maxcpus > 0 ? maxcpus : cpus; + } else if (sockets == 0) { + cores = cores > 0 ? cores : 1; + threads = threads > 0 ? threads : 1; + sockets = maxcpus / (cores * threads); } else if (cores == 0) { threads = threads > 0 ? threads : 1; - cores = cpus / (sockets * threads); - cores = cores > 0 ? cores : 1; + cores = maxcpus / (sockets * threads); } else if (threads == 0) { - threads = cpus / (cores * sockets); - threads = threads > 0 ? threads : 1; - } else if (sockets * cores * threads < cpus) { + threads = maxcpus / (sockets * cores); + } + + if (sockets * cores * threads < cpus) { error_setg(errp, "cpu topology: " "sockets (%u) * cores (%u) * threads (%u) < " "smp_cpus (%u)", @@ -785,8 +787,6 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) return; } - maxcpus = maxcpus > 0 ? maxcpus : cpus; - if (maxcpus < cpus) { error_setg(errp, "maxcpus must be equal to or greater than smp"); return; diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 8599a9b527..9399e2906d 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -727,24 +727,26 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err dies = dies > 0 ? dies : 1; /* compute missing values, prefer sockets over cores over threads */ - if (cpus == 0 || sockets == 0) { + maxcpus = maxcpus > 0 ? maxcpus : cpus; + + if (cpus == 0) { + sockets = sockets > 0 ? sockets : 1; cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; - if (cpus == 0) { - sockets = sockets > 0 ? sockets : 1; - cpus = cores * threads * dies * sockets; - } else { - maxcpus = maxcpus > 0 ? maxcpus : cpus; - sockets = maxcpus / (dies * cores * threads); - } + cpus = sockets * dies * cores * threads; + maxcpus = maxcpus > 0 ? maxcpus : cpus; + } else if (sockets == 0) { + cores = cores > 0 ? cores : 1; + threads = threads > 0 ? threads : 1; + sockets = maxcpus / (dies * cores * threads); } else if (cores == 0) { threads = threads > 0 ? threads : 1; - cores = cpus / (sockets * dies * threads); - cores = cores > 0 ? cores : 1; + cores = maxcpus / (sockets * dies * threads); } else if (threads == 0) { - threads = cpus / (cores * dies * sockets); - threads = threads > 0 ? threads : 1; - } else if (sockets * dies * cores * threads < cpus) { + threads = maxcpus / (sockets * dies * cores); + } + + if (sockets * dies * cores * threads < cpus) { error_setg(errp, "cpu topology: " "sockets (%u) * dies (%u) * cores (%u) * threads (%u) < " "smp_cpus (%u)", @@ -752,8 +754,6 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err return; } - maxcpus = maxcpus > 0 ? maxcpus : cpus; - if (maxcpus < cpus) { error_setg(errp, "maxcpus must be equal to or greater than smp"); return; -- 2.23.0