commit
  (5cdc9b76e3 vl.c: Remove dead assignment)
removed sockets calculation when 'sockets' weren't provided on CLI
since there wasn't any users for it back then. Exiting checks
are neither reachable
   } else if (sockets * cores * threads < cpus) {
or nor triggable
   if (sockets * cores * threads > max_cpus)
so we weren't noticing wrong topology since then, since users
recalculate sockets adhoc on their own.

However with deprecation check it becomes noticable, for example
  -smp 2
will start printing warning:
  "warning: Invalid CPU topology deprecated: sockets (1) * cores (1) * threads (1) != maxcpus (2)"
calculating sockets if they weren't specified.

Fix it by returning back sockets calculation if it's omited on CLI.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
---
 vl.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/vl.c b/vl.c
index 7fd700e..9e56696 100644
--- a/vl.c
+++ b/vl.c
@@ -1210,11 +1210,14 @@ static void smp_parse(QemuOpts *opts)
 
         /* compute missing values, prefer sockets over cores over threads */
         if (cpus == 0 || sockets == 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 {
+                max_cpus = qemu_opt_get_number(opts, "maxcpus", cpus);
+                sockets = max_cpus / (cores * threads);
             }
         } else if (cores == 0) {
             threads = threads > 0 ? threads : 1;
-- 
2.7.4

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On 9/12/18 11:19 AM, Igor Mammedov wrote:
> commit
>    (5cdc9b76e3 vl.c: Remove dead assignment)
> removed sockets calculation when 'sockets' weren't provided on CLI
> since there wasn't any users for it back then. Exiting checks
> are neither reachable
>     } else if (sockets * cores * threads < cpus) {
> or nor triggable

s/triggable/triggerable/

>     if (sockets * cores * threads > max_cpus)
> so we weren't noticing wrong topology since then, since users
> recalculate sockets adhoc on their own.
> 
> However with deprecation check it becomes noticable, for example
>    -smp 2
> will start printing warning:
>    "warning: Invalid CPU topology deprecated: sockets (1) * cores (1) * threads (1) != maxcpus (2)"
> calculating sockets if they weren't specified.
> 
> Fix it by returning back sockets calculation if it's omited on CLI.

s/omited/omitted/

> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> Reviewed-by: Andrew Jones <drjones@redhat.com>
> ---
>   vl.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/vl.c b/vl.c
> index 7fd700e..9e56696 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -1210,11 +1210,14 @@ static void smp_parse(QemuOpts *opts)
>   
>           /* compute missing values, prefer sockets over cores over threads */
>           if (cpus == 0 || sockets == 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 {
> +                max_cpus = qemu_opt_get_number(opts, "maxcpus", cpus);
> +                sockets = max_cpus / (cores * threads);
>               }
>           } else if (cores == 0) {
>               threads = threads > 0 ? threads : 1;
> 

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org