Re: [PATCH-for-10.1 2/4] tcg: Move qemu_tcg_mttcg_enabled() to 'system/tcg.h'

[Richard Henderson <richard.henderson@linaro.org>]

On 3/21/25 08:59, Philippe Mathieu-Daudé wrote:
> qemu_tcg_mttcg_enabled() is specific to 1/ TCG and
> 2/ system emulation. Move the prototype declaration
> to "system/tcg.h", reducing 'mttcg_enabled' variable
> scope.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/hw/core/cpu.h      |  9 ---------
>   include/system/tcg.h       |  8 ++++++++
>   accel/tcg/tcg-all.c        | 11 ++++++++++-
>   target/riscv/tcg/tcg-cpu.c |  1 +
>   tcg/region.c               |  4 +++-
>   5 files changed, 22 insertions(+), 11 deletions(-)
> 
> diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
> index 5d11d26556a..54570d21aea 100644
> --- a/include/hw/core/cpu.h
> +++ b/include/hw/core/cpu.h
> @@ -597,15 +597,6 @@ extern CPUTailQ cpus_queue;
>   
>   extern __thread CPUState *current_cpu;
>   
> -/**
> - * qemu_tcg_mttcg_enabled:
> - * Check whether we are running MultiThread TCG or not.
> - *
> - * Returns: %true if we are in MTTCG mode %false otherwise.
> - */
> -extern bool mttcg_enabled;
> -#define qemu_tcg_mttcg_enabled() (mttcg_enabled)
> -
>   /**
>    * cpu_paging_enabled:
>    * @cpu: The CPU whose state is to be inspected.
> diff --git a/include/system/tcg.h b/include/system/tcg.h
> index 73229648c63..7622dcea302 100644
> --- a/include/system/tcg.h
> +++ b/include/system/tcg.h
> @@ -17,4 +17,12 @@ extern bool tcg_allowed;
>   #define tcg_enabled() 0
>   #endif
>   
> +/**
> + * qemu_tcg_mttcg_enabled:
> + * Check whether we are running MultiThread TCG or not.
> + *
> + * Returns: %true if we are in MTTCG mode %false otherwise.
> + */
> +bool qemu_tcg_mttcg_enabled(void);
> +
>   #endif
> diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c
> index cb632cc8cc7..d75ecf531b6 100644
> --- a/accel/tcg/tcg-all.c
> +++ b/accel/tcg/tcg-all.c
> @@ -38,6 +38,7 @@
>   #include "hw/qdev-core.h"
>   #else
>   #include "hw/boards.h"
> +#include "system/tcg.h"
>   #endif
>   #include "internal-common.h"
>   #include "cpu-param.h"
> @@ -58,6 +59,15 @@ typedef struct TCGState TCGState;
>   DECLARE_INSTANCE_CHECKER(TCGState, TCG_STATE,
>                            TYPE_TCG_ACCEL)
>   
> +static bool mttcg_enabled;
> +
> +#ifndef CONFIG_USER_ONLY
> +bool qemu_tcg_mttcg_enabled(void)
> +{
> +    return mttcg_enabled;
> +}
> +#endif

It would appear (and it makes sense) that mttcg_enabled is only set for user-mode.  I 
think you should be conditionalizing the variable for system mode as well.


r~