On 1/31/21 4:23 PM, Philippe Mathieu-Daudé wrote: > On 1/31/21 3:18 PM, Claudio Fontana wrote: >> On 1/31/21 12:50 PM, Philippe Mathieu-Daudé wrote: >>> Modules are registered early with type_register_static(). >>> >>> We would like to call tcg_enabled() when registering QOM types, >> >> >> Hi Philippe, >> >> could this not be controlled by meson at this stage? >> On X86, I register the tcg-specific types in tcg/* in modules that are only built for TCG. >> >> Maybe tcg_builtin() is useful anyway, thinking long term at loadable modules, >> but there we are interested in whether tcg code is available or not, regardless of whether it's builtin, >> or needs to be loaded via a .so plugin.. >> >> maybe tcg_available()? > > The alternatives I found: > > - reorder things in vl.c? > > - use ugly #ifdef'ry, see this patch: > https://lists.gnu.org/archive/html/qemu-devel/2021-01/msg08037.html Not sure it's that ugly, if it is followed (or replaced by) exporting those pieces to separate files, which are only built by meson on CONFIG_TCG. I did not try to do it, so you know best of course. Ciao, Claudio > > - this earlier approach I previously discarded: > > -- >8 -- > diff --git a/include/qom/object.h b/include/qom/object.h > index d378f13a116..30590c6fac3 100644 > --- a/include/qom/object.h > +++ b/include/qom/object.h > @@ -403,9 +403,12 @@ struct Object > * parent class initialization has occurred, but before the class itself > * is initialized. This is the function to use to undo the effects of > * memcpy from the parent class to the descendants. > - * @class_data: Data to pass to the @class_init, > + * @class_data: Data to pass to the @class_registerable, @class_init, > * @class_base_init. This can be useful when building dynamic > * classes. > + * @registerable: This function is called when modules are registered, > + * prior to any class initialization. When present and returning %false, > + * the type is not registered, the class is not present (not usable). > * @interfaces: The list of interfaces associated with this type. This > * should point to a static array that's terminated with a zero filled > * element. > @@ -428,6 +431,7 @@ struct TypeInfo > void (*class_base_init)(ObjectClass *klass, void *data); > void *class_data; > > + bool (*registerable)(void *data); > InterfaceInfo *interfaces; > }; > > diff --git a/qom/object.c b/qom/object.c > index 2fa0119647c..0febaffa12e 100644 > --- a/qom/object.c > +++ b/qom/object.c > @@ -138,6 +138,10 @@ static TypeImpl *type_new(const TypeInfo *info) > static TypeImpl *type_register_internal(const TypeInfo *info) > { > TypeImpl *ti; > + > + if (info->registerable && !info->registerable(info->class_data)) { > + return NULL; > + } > ti = type_new(info); > > type_table_add(ti); > > diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c > index 990509d3852..1a2b1889da4 100644 > --- a/hw/arm/raspi.c > +++ b/hw/arm/raspi.c > @@ -24,6 +24,7 @@ > #include "hw/loader.h" > #include "hw/arm/boot.h" > #include "sysemu/sysemu.h" > +#include "sysemu/tcg.h" > #include "qom/object.h" > > #define SMPBOOT_ADDR 0x300 /* this should leave enough space for > ATAGS */ > @@ -368,18 +369,26 @@ static void raspi3b_machine_class_init(ObjectClass > *oc, void *data) > }; > #endif /* TARGET_AARCH64 */ > > +static bool raspi_machine_requiring_tcg_accel(void *data) > +{ > + return tcg_builtin(); > +} > + > static const TypeInfo raspi_machine_types[] = { > { > .name = MACHINE_TYPE_NAME("raspi0"), > .parent = TYPE_RASPI_MACHINE, > + .registerable = raspi_machine_requiring_tcg_accel, > .class_init = raspi0_machine_class_init, > }, { > .name = MACHINE_TYPE_NAME("raspi1ap"), > .parent = TYPE_RASPI_MACHINE, > + .registerable = raspi_machine_requiring_tcg_accel, > .class_init = raspi1ap_machine_class_init, > }, { > .name = MACHINE_TYPE_NAME("raspi2b"), > .parent = TYPE_RASPI_MACHINE, > + .registerable = raspi_machine_requiring_tcg_accel, > .class_init = raspi2b_machine_class_init, > #ifdef TARGET_AARCH64 > }, { > --- > >> >> Ciao, >> >> Claudio >> >>> but tcg_enabled() returns tcg_allowed which is a runtime property >>> initialized later (See commit 2f181fbd5a9 which introduced the >>> MachineInitPhase in "hw/qdev-core.h" representing the different >>> phases of machine initialization and commit 0427b6257e2 which >>> document the initialization order). >>> >>> As we are only interested if the TCG accelerator is builtin, >>> regardless of being enabled, introduce the tcg_builtin() helper. >>> >>> Signed-off-by: Philippe Mathieu-Daudé <f4bug@xxxxxxxxx> >>> --- >>> Cc: Markus Armbruster <armbru@xxxxxxxxxx> >>> --- >>> include/sysemu/tcg.h | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/include/sysemu/tcg.h b/include/sysemu/tcg.h >>> index 00349fb18a7..6ac5c2ca89d 100644 >>> --- a/include/sysemu/tcg.h >>> +++ b/include/sysemu/tcg.h >>> @@ -13,8 +13,10 @@ void tcg_exec_init(unsigned long tb_size, int splitwx); >>> #ifdef CONFIG_TCG >>> extern bool tcg_allowed; >>> #define tcg_enabled() (tcg_allowed) >>> +#define tcg_builtin() 1 >>> #else >>> #define tcg_enabled() 0 >>> +#define tcg_builtin() 0 >>> #endif >>> >>> #endif >>> >> >
