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[RFC,4/6] machine: Uniformly use maxcpus to calculate the missing values

Message ID 20210702100739.13672-5-wangyanan55@huawei.com
State New
Headers show
Series machine: smp parsing fixes and improvement | expand

Commit Message

wangyanan (Y) July 2, 2021, 10:07 a.m. UTC
We are currently using maxcpus to calculate value of sockets but using
cpus to calculate value of cores/threads. This makes cmdlines like
"-smp 8,maxcpus=12,cores=4" work while "-smp 8,maxcpus=12,sockets=3"
break the invalid cpu topology check.

This patch allows us to uniformly use maxcpus to calculate the missing
values. Also the if branch of "cpus == 0 || sockets == 0" was splited
into branches of "cpus == 0" and "sockets == 0" so that we can clearly
figure out that we are parsing -smp cmdlines with a preference of cpus
over sockets over cores over threads.

Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
---
 hw/core/machine.c | 36 +++++++++++++++++++-----------------
 hw/i386/pc.c      | 37 +++++++++++++++++++------------------
 2 files changed, 38 insertions(+), 35 deletions(-)

Comments

Andrew Jones July 12, 2021, 3:25 p.m. UTC | #1
On Fri, Jul 02, 2021 at 06:07:37PM +0800, Yanan Wang wrote:
> We are currently using maxcpus to calculate value of sockets but using
> cpus to calculate value of cores/threads. This makes cmdlines like
> "-smp 8,maxcpus=12,cores=4" work while "-smp 8,maxcpus=12,sockets=3"
> break the invalid cpu topology check.
> 
> This patch allows us to uniformly use maxcpus to calculate the missing
> values. Also the if branch of "cpus == 0 || sockets == 0" was splited
> into branches of "cpus == 0" and "sockets == 0" so that we can clearly
> figure out that we are parsing -smp cmdlines with a preference of cpus
> over sockets over cores over threads.
> 
> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
> ---
>  hw/core/machine.c | 36 +++++++++++++++++++-----------------
>  hw/i386/pc.c      | 37 +++++++++++++++++++------------------
>  2 files changed, 38 insertions(+), 35 deletions(-)
> 
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index 1e194677cd..58882835be 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -752,34 +752,36 @@ 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);
> -            sockets = sockets > 0 ? sockets : 1;
> -        }
> +        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);
> +        sockets = sockets > 0 ? sockets : 1;

As stated in the other patch, this rounding up of a fractional sockets
shouldn't be here. maxcpus or (cpus==maxcpus) should always be selected by
the user to be a product of whole number sockets, cores, threads.

>      } else if (cores == 0) {
>          threads = threads > 0 ? threads : 1;
> -        cores = cpus / (sockets * threads);
> +        cores = maxcpus / (sockets * threads);
>          cores = cores > 0 ? cores : 1;

Now that we're using maxcpus for the calculation, then no rounding for
cores either...

>      } else if (threads == 0) {
> -        threads = cpus / (cores * sockets);
> +        threads = maxcpus / (sockets * cores);
>          threads = threads > 0 ? threads : 1;

...or threads.

> -    } else if (sockets * cores * threads < cpus) {
> +    }
> +
> +    if (sockets * cores * threads < cpus) {
>          error_setg(errp, "cpu topology: "
> -                   "sockets (%u) * cores (%u) * threads (%u) < "
> -                   "smp_cpus (%u)",
> +                   "sockets (%u) * cores (%u) * threads (%u) "
> +                   "< smp_cpus (%u)",

Why make this change?

>                     sockets, cores, threads, cpus);
>          return;
>      }
>  
> -    maxcpus = maxcpus > 0 ? maxcpus : cpus;
> -
>      if (maxcpus < cpus) {
>          error_setg(errp, "maxcpus must be equal to or greater than smp");
>          return;
> @@ -795,9 +797,9 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
>      }
>  
>      ms->smp.cpus = cpus;
> +    ms->smp.sockets = sockets;
>      ms->smp.cores = cores;
>      ms->smp.threads = threads;
> -    ms->smp.sockets = sockets;
>      ms->smp.max_cpus = maxcpus;
>  }
>  
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 93d1f12a49..1812f33ab1 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -721,35 +721,36 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
>  
>      /* compute missing values, prefer sockets over cores over threads */
>      dies = dies > 0 ? dies : 1;
> +    maxcpus = maxcpus > 0 ? maxcpus : cpus;
>  
> -    if (cpus == 0 || sockets == 0) {
> +    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);
> -            sockets = sockets > 0 ? sockets : 1;
> -        }
> +        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);
> +        sockets = sockets > 0 ? sockets : 1;
>      } else if (cores == 0) {
>          threads = threads > 0 ? threads : 1;
> -        cores = cpus / (sockets * dies * threads);
> +        cores = maxcpus / (sockets * dies * threads);
>          cores = cores > 0 ? cores : 1;
>      } else if (threads == 0) {
> -        threads = cpus / (cores * dies * sockets);
> +        threads = maxcpus / (sockets * dies * cores);
>          threads = threads > 0 ? threads : 1;
> -    } else if (sockets * dies * cores * threads < cpus) {
> +    }
> +
> +    if (sockets * dies * cores * threads < cpus) {
>          error_setg(errp, "cpu topology: "
> -                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) < "
> -                   "smp_cpus (%u)",
> +                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) "
> +                   "< smp_cpus (%u)",
>                     sockets, dies, cores, threads, cpus);
>          return;
>      }
>  

Same comments as for the general function.

Thanks,
drew

> -    maxcpus = maxcpus > 0 ? maxcpus : cpus;
> -
>      if (maxcpus < cpus) {
>          error_setg(errp, "maxcpus must be equal to or greater than smp");
>          return;
> @@ -765,10 +766,10 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
>      }
>  
>      ms->smp.cpus = cpus;
> -    ms->smp.cores = cores;
> -    ms->smp.threads = threads;
>      ms->smp.sockets = sockets;
>      ms->smp.dies = dies;
> +    ms->smp.cores = cores;
> +    ms->smp.threads = threads;
>      ms->smp.max_cpus = maxcpus;
>  }
>  
> -- 
> 2.19.1
>
wangyanan (Y) July 13, 2021, 7:25 a.m. UTC | #2
Hi Drew,

On 2021/7/12 23:25, Andrew Jones wrote:
> On Fri, Jul 02, 2021 at 06:07:37PM +0800, Yanan Wang wrote:
>> We are currently using maxcpus to calculate value of sockets but using
>> cpus to calculate value of cores/threads. This makes cmdlines like
>> "-smp 8,maxcpus=12,cores=4" work while "-smp 8,maxcpus=12,sockets=3"
>> break the invalid cpu topology check.
>>
>> This patch allows us to uniformly use maxcpus to calculate the missing
>> values. Also the if branch of "cpus == 0 || sockets == 0" was splited
>> into branches of "cpus == 0" and "sockets == 0" so that we can clearly
>> figure out that we are parsing -smp cmdlines with a preference of cpus
>> over sockets over cores over threads.
>>
>> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
>> ---
>>   hw/core/machine.c | 36 +++++++++++++++++++-----------------
>>   hw/i386/pc.c      | 37 +++++++++++++++++++------------------
>>   2 files changed, 38 insertions(+), 35 deletions(-)
>>
>> diff --git a/hw/core/machine.c b/hw/core/machine.c
>> index 1e194677cd..58882835be 100644
>> --- a/hw/core/machine.c
>> +++ b/hw/core/machine.c
>> @@ -752,34 +752,36 @@ 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);
>> -            sockets = sockets > 0 ? sockets : 1;
>> -        }
>> +        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);
>> +        sockets = sockets > 0 ? sockets : 1;
> As stated in the other patch, this rounding up of a fractional sockets
> shouldn't be here. maxcpus or (cpus==maxcpus) should always be selected by
> the user to be a product of whole number sockets, cores, threads.
I also default sockets to 1 if computed as zero because we are doing
this for cores/threads and I did't see the difference between them.

Anyway, now that we are using maxcpus for all calculations, so we can
either get rid of all the rounding-ups for sockets/cores/threads or just
keep them all.

With the rouding-up, we get:
-smp cpus=12,cores=16,maxcpus=12 --> -smp 
cpus=12,sockets=0,cores=16,threads=1,maxcpus=12 --> error_report

without the rounding-up we get:
-smp cpus=12,cores=16,maxcpus=12 --> -smp 
cpus=12,sockets=1,cores=16,threads=1,maxcpus=12 --> error_report

We will both get an error report as expected, but I can get rid of the 
rounding if it's preferred.
>>       } else if (cores == 0) {
>>           threads = threads > 0 ? threads : 1;
>> -        cores = cpus / (sockets * threads);
>> +        cores = maxcpus / (sockets * threads);
>>           cores = cores > 0 ? cores : 1;
> Now that we're using maxcpus for the calculation, then no rounding for
> cores either...
>
>>       } else if (threads == 0) {
>> -        threads = cpus / (cores * sockets);
>> +        threads = maxcpus / (sockets * cores);
>>           threads = threads > 0 ? threads : 1;
> ...or threads.
>
>> -    } else if (sockets * cores * threads < cpus) {
>> +    }
>> +
>> +    if (sockets * cores * threads < cpus) {
>>           error_setg(errp, "cpu topology: "
>> -                   "sockets (%u) * cores (%u) * threads (%u) < "
>> -                   "smp_cpus (%u)",
>> +                   "sockets (%u) * cores (%u) * threads (%u) "
>> +                   "< smp_cpus (%u)",
> Why make this change?
No need actually, will change it back. :)
>>                      sockets, cores, threads, cpus);
>>           return;
>>       }
>>   
>> -    maxcpus = maxcpus > 0 ? maxcpus : cpus;
>> -
>>       if (maxcpus < cpus) {
>>           error_setg(errp, "maxcpus must be equal to or greater than smp");
>>           return;
>> @@ -795,9 +797,9 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
>>       }
>>   
>>       ms->smp.cpus = cpus;
>> +    ms->smp.sockets = sockets;
>>       ms->smp.cores = cores;
>>       ms->smp.threads = threads;
>> -    ms->smp.sockets = sockets;
>>       ms->smp.max_cpus = maxcpus;
>>   }
>>   
>> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
>> index 93d1f12a49..1812f33ab1 100644
>> --- a/hw/i386/pc.c
>> +++ b/hw/i386/pc.c
>> @@ -721,35 +721,36 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
>>   
>>       /* compute missing values, prefer sockets over cores over threads */
>>       dies = dies > 0 ? dies : 1;
>> +    maxcpus = maxcpus > 0 ? maxcpus : cpus;
>>   
>> -    if (cpus == 0 || sockets == 0) {
>> +    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);
>> -            sockets = sockets > 0 ? sockets : 1;
>> -        }
>> +        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);
>> +        sockets = sockets > 0 ? sockets : 1;
>>       } else if (cores == 0) {
>>           threads = threads > 0 ? threads : 1;
>> -        cores = cpus / (sockets * dies * threads);
>> +        cores = maxcpus / (sockets * dies * threads);
>>           cores = cores > 0 ? cores : 1;
>>       } else if (threads == 0) {
>> -        threads = cpus / (cores * dies * sockets);
>> +        threads = maxcpus / (sockets * dies * cores);
>>           threads = threads > 0 ? threads : 1;
>> -    } else if (sockets * dies * cores * threads < cpus) {
>> +    }
>> +
>> +    if (sockets * dies * cores * threads < cpus) {
>>           error_setg(errp, "cpu topology: "
>> -                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) < "
>> -                   "smp_cpus (%u)",
>> +                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) "
>> +                   "< smp_cpus (%u)",
>>                      sockets, dies, cores, threads, cpus);
>>           return;
>>       }
>>   
> Same comments as for the general function.
>
> Thanks,
> drew
>
>> -    maxcpus = maxcpus > 0 ? maxcpus : cpus;
>> -
>>       if (maxcpus < cpus) {
>>           error_setg(errp, "maxcpus must be equal to or greater than smp");
>>           return;
>> @@ -765,10 +766,10 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
>>       }
>>   
>>       ms->smp.cpus = cpus;
>> -    ms->smp.cores = cores;
>> -    ms->smp.threads = threads;
>>       ms->smp.sockets = sockets;
>>       ms->smp.dies = dies;
>> +    ms->smp.cores = cores;
>> +    ms->smp.threads = threads;
>>       ms->smp.max_cpus = maxcpus;
>>   }
>>   
>> -- 
>> 2.19.1
>>
Thanks,
Yanan
.
> .
wangyanan (Y) July 13, 2021, 7:49 a.m. UTC | #3
On 2021/7/2 18:07, Yanan Wang wrote:
> We are currently using maxcpus to calculate value of sockets but using
> cpus to calculate value of cores/threads. This makes cmdlines like
> "-smp 8,maxcpus=12,cores=4" work while "-smp 8,maxcpus=12,sockets=3"
> break the invalid cpu topology check.
>
> This patch allows us to uniformly use maxcpus to calculate the missing
> values. Also the if branch of "cpus == 0 || sockets == 0" was splited
> into branches of "cpus == 0" and "sockets == 0" so that we can clearly
> figure out that we are parsing -smp cmdlines with a preference of cpus
> over sockets over cores over threads.
BTW, after this patch, configs like:
-smp maxcpus=16 --> -smp 1,sockets=1,cores=1,threads=1,maxcpus=16
-smp sockets=2,maxcpus=16 --> -smp 2,sockets=2,cores=1,threads=1,maxcpus=16
......
still can not work. So I suggest to use the parameters computed by 
maxcpus to calculate
the value of cpus if it's omitted. The diff based on this patch is:

diff --git a/hw/core/machine.c b/hw/core/machine.c
index 93c5227920..924c48fd43 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -757,13 +757,7 @@ static void smp_parse(MachineState *ms, 
SMPConfiguration *config, Error **errp)
      /* compute missing values, prefer sockets over cores over threads */
      maxcpus = maxcpus > 0 ? maxcpus : cpus;

-    if (cpus == 0) {
-        sockets = sockets > 0 ? sockets : 1;
-        cores = cores > 0 ? cores : 1;
-        threads = threads > 0 ? threads : 1;
-        cpus = sockets * cores * threads;
-        maxcpus = maxcpus > 0 ? maxcpus : cpus;
-    } else if (sockets == 0) {
+    if (sockets == 0) {
          cores = cores > 0 ? cores : 1;
          threads = threads > 0 ? threads : 1;
          sockets = maxcpus / (cores * threads);
@@ -777,6 +771,9 @@ static void smp_parse(MachineState *ms, 
SMPConfiguration *config, Error **errp)
          threads = threads > 0 ? threads : 1;
      }

+    cpus = cpus > 0 ? cpus : sockets * cores * threads;
+    maxcpus = maxcpus > 0 ? maxcpus : cpus;
+
      if (sockets * cores * threads < cpus) {
          error_setg(errp, "cpu topology: "
                     "sockets (%u) * cores (%u) * threads (%u) < "


Thanks,
Yanan
.
> Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
> ---
>   hw/core/machine.c | 36 +++++++++++++++++++-----------------
>   hw/i386/pc.c      | 37 +++++++++++++++++++------------------
>   2 files changed, 38 insertions(+), 35 deletions(-)
>
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index 1e194677cd..58882835be 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -752,34 +752,36 @@ 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);
> -            sockets = sockets > 0 ? sockets : 1;
> -        }
> +        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);
> +        sockets = sockets > 0 ? sockets : 1;
>       } else if (cores == 0) {
>           threads = threads > 0 ? threads : 1;
> -        cores = cpus / (sockets * threads);
> +        cores = maxcpus / (sockets * threads);
>           cores = cores > 0 ? cores : 1;
>       } else if (threads == 0) {
> -        threads = cpus / (cores * sockets);
> +        threads = maxcpus / (sockets * cores);
>           threads = threads > 0 ? threads : 1;
> -    } else if (sockets * cores * threads < cpus) {
> +    }
> +
> +    if (sockets * cores * threads < cpus) {
>           error_setg(errp, "cpu topology: "
> -                   "sockets (%u) * cores (%u) * threads (%u) < "
> -                   "smp_cpus (%u)",
> +                   "sockets (%u) * cores (%u) * threads (%u) "
> +                   "< smp_cpus (%u)",
>                      sockets, cores, threads, cpus);
>           return;
>       }
>   
> -    maxcpus = maxcpus > 0 ? maxcpus : cpus;
> -
>       if (maxcpus < cpus) {
>           error_setg(errp, "maxcpus must be equal to or greater than smp");
>           return;
> @@ -795,9 +797,9 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
>       }
>   
>       ms->smp.cpus = cpus;
> +    ms->smp.sockets = sockets;
>       ms->smp.cores = cores;
>       ms->smp.threads = threads;
> -    ms->smp.sockets = sockets;
>       ms->smp.max_cpus = maxcpus;
>   }
>   
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 93d1f12a49..1812f33ab1 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -721,35 +721,36 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
>   
>       /* compute missing values, prefer sockets over cores over threads */
>       dies = dies > 0 ? dies : 1;
> +    maxcpus = maxcpus > 0 ? maxcpus : cpus;
>   
> -    if (cpus == 0 || sockets == 0) {
> +    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);
> -            sockets = sockets > 0 ? sockets : 1;
> -        }
> +        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);
> +        sockets = sockets > 0 ? sockets : 1;
>       } else if (cores == 0) {
>           threads = threads > 0 ? threads : 1;
> -        cores = cpus / (sockets * dies * threads);
> +        cores = maxcpus / (sockets * dies * threads);
>           cores = cores > 0 ? cores : 1;
>       } else if (threads == 0) {
> -        threads = cpus / (cores * dies * sockets);
> +        threads = maxcpus / (sockets * dies * cores);
>           threads = threads > 0 ? threads : 1;
> -    } else if (sockets * dies * cores * threads < cpus) {
> +    }
> +
> +    if (sockets * dies * cores * threads < cpus) {
>           error_setg(errp, "cpu topology: "
> -                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) < "
> -                   "smp_cpus (%u)",
> +                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) "
> +                   "< smp_cpus (%u)",
>                      sockets, dies, cores, threads, cpus);
>           return;
>       }
>   
> -    maxcpus = maxcpus > 0 ? maxcpus : cpus;
> -
>       if (maxcpus < cpus) {
>           error_setg(errp, "maxcpus must be equal to or greater than smp");
>           return;
> @@ -765,10 +766,10 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
>       }
>   
>       ms->smp.cpus = cpus;
> -    ms->smp.cores = cores;
> -    ms->smp.threads = threads;
>       ms->smp.sockets = sockets;
>       ms->smp.dies = dies;
> +    ms->smp.cores = cores;
> +    ms->smp.threads = threads;
>       ms->smp.max_cpus = maxcpus;
>   }
>
diff mbox series

Patch

diff --git a/hw/core/machine.c b/hw/core/machine.c
index 1e194677cd..58882835be 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -752,34 +752,36 @@  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);
-            sockets = sockets > 0 ? sockets : 1;
-        }
+        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);
+        sockets = sockets > 0 ? sockets : 1;
     } else if (cores == 0) {
         threads = threads > 0 ? threads : 1;
-        cores = cpus / (sockets * threads);
+        cores = maxcpus / (sockets * threads);
         cores = cores > 0 ? cores : 1;
     } else if (threads == 0) {
-        threads = cpus / (cores * sockets);
+        threads = maxcpus / (sockets * cores);
         threads = threads > 0 ? threads : 1;
-    } else if (sockets * cores * threads < cpus) {
+    }
+
+    if (sockets * cores * threads < cpus) {
         error_setg(errp, "cpu topology: "
-                   "sockets (%u) * cores (%u) * threads (%u) < "
-                   "smp_cpus (%u)",
+                   "sockets (%u) * cores (%u) * threads (%u) "
+                   "< smp_cpus (%u)",
                    sockets, cores, threads, cpus);
         return;
     }
 
-    maxcpus = maxcpus > 0 ? maxcpus : cpus;
-
     if (maxcpus < cpus) {
         error_setg(errp, "maxcpus must be equal to or greater than smp");
         return;
@@ -795,9 +797,9 @@  static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp)
     }
 
     ms->smp.cpus = cpus;
+    ms->smp.sockets = sockets;
     ms->smp.cores = cores;
     ms->smp.threads = threads;
-    ms->smp.sockets = sockets;
     ms->smp.max_cpus = maxcpus;
 }
 
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 93d1f12a49..1812f33ab1 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -721,35 +721,36 @@  static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
 
     /* compute missing values, prefer sockets over cores over threads */
     dies = dies > 0 ? dies : 1;
+    maxcpus = maxcpus > 0 ? maxcpus : cpus;
 
-    if (cpus == 0 || sockets == 0) {
+    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);
-            sockets = sockets > 0 ? sockets : 1;
-        }
+        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);
+        sockets = sockets > 0 ? sockets : 1;
     } else if (cores == 0) {
         threads = threads > 0 ? threads : 1;
-        cores = cpus / (sockets * dies * threads);
+        cores = maxcpus / (sockets * dies * threads);
         cores = cores > 0 ? cores : 1;
     } else if (threads == 0) {
-        threads = cpus / (cores * dies * sockets);
+        threads = maxcpus / (sockets * dies * cores);
         threads = threads > 0 ? threads : 1;
-    } else if (sockets * dies * cores * threads < cpus) {
+    }
+
+    if (sockets * dies * cores * threads < cpus) {
         error_setg(errp, "cpu topology: "
-                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) < "
-                   "smp_cpus (%u)",
+                   "sockets (%u) * dies (%u) * cores (%u) * threads (%u) "
+                   "< smp_cpus (%u)",
                    sockets, dies, cores, threads, cpus);
         return;
     }
 
-    maxcpus = maxcpus > 0 ? maxcpus : cpus;
-
     if (maxcpus < cpus) {
         error_setg(errp, "maxcpus must be equal to or greater than smp");
         return;
@@ -765,10 +766,10 @@  static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err
     }
 
     ms->smp.cpus = cpus;
-    ms->smp.cores = cores;
-    ms->smp.threads = threads;
     ms->smp.sockets = sockets;
     ms->smp.dies = dies;
+    ms->smp.cores = cores;
+    ms->smp.threads = threads;
     ms->smp.max_cpus = maxcpus;
 }