Both cpu-pm and mem-lock are related to system resource overcommit, but
they are separate from each other, in terms of how they are realized,
and of course, they are applied to different system resources.

It's tempting to use separate command lines to specify their behavior.
e.g., in the following example, the cpu-pm command is quietly
overwritten, and it's not easy to notice it without careful inspection.

  --overcommit mem-lock=on
  --overcommit cpu-pm=on

Fixes: c8c9dc42b7ca ("Remove the deprecated -realtime option")
Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Zide Chen <zide.chen@intel.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
---

V3: added Reviewed-by

v2:
Thanks to Thomas' suggestion, changed to this better approach, which
is more generic and can handle situations like: "enabled the option in
the config file, and now you'd like to disable it on the command line
again".

 system/vl.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/system/vl.c b/system/vl.c
index a3eede5fa5b8..dfa6cdd9283b 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -3545,8 +3545,8 @@ void qemu_init(int argc, char **argv)
                 if (!opts) {
                     exit(1);
                 }
-                enable_mlock = qemu_opt_get_bool(opts, "mem-lock", false);
-                enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", false);
+                enable_mlock = qemu_opt_get_bool(opts, "mem-lock", enable_mlock);
+                enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", enable_cpu_pm);
                 break;
             case QEMU_OPTION_compat:
                 {
-- 
2.34.1

On Mon,  3 Jun 2024 17:02:21 -0700
Zide Chen <zide.chen@intel.com> wrote:

> Both cpu-pm and mem-lock are related to system resource overcommit, but
> they are separate from each other, in terms of how they are realized,
> and of course, they are applied to different system resources.
> 
> It's tempting to use separate command lines to specify their behavior.
> e.g., in the following example, the cpu-pm command is quietly
> overwritten, and it's not easy to notice it without careful inspection.
> 
>   --overcommit mem-lock=on
>   --overcommit cpu-pm=on
> 
> Fixes: c8c9dc42b7ca ("Remove the deprecated -realtime option")
> Suggested-by: Thomas Huth <thuth@redhat.com>
> Signed-off-by: Zide Chen <zide.chen@intel.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> Reviewed-by: Zhao Liu <zhao1.liu@intel.com>

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
> 
> V3: added Reviewed-by
> 
> v2:
> Thanks to Thomas' suggestion, changed to this better approach, which
> is more generic and can handle situations like: "enabled the option in
> the config file, and now you'd like to disable it on the command line
> again".
> 
>  system/vl.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/system/vl.c b/system/vl.c
> index a3eede5fa5b8..dfa6cdd9283b 100644
> --- a/system/vl.c
> +++ b/system/vl.c
> @@ -3545,8 +3545,8 @@ void qemu_init(int argc, char **argv)
>                  if (!opts) {
>                      exit(1);
>                  }
> -                enable_mlock = qemu_opt_get_bool(opts, "mem-lock", false);
> -                enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", false);
> +                enable_mlock = qemu_opt_get_bool(opts, "mem-lock", enable_mlock);
> +                enable_cpu_pm = qemu_opt_get_bool(opts, "cpu-pm", enable_cpu_pm);
>                  break;
>              case QEMU_OPTION_compat:
>                  {