Hi On Mon, Dec 9, 2019 at 7:07 PM Paolo Bonzini <pbonz...@redhat.com> wrote: > > Move everything related to mttcg_enabled in accel/tcg/tcg-all.c, > which will make even more sense when "thread" becomes a QOM property. > > For now, initializing mttcg_enabled in the instance_init function > prepares for the next patch, which will only invoke qemu_tcg_configure > when the command line includes a -accel option. > > Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> > --- > accel/tcg/tcg-all.c | 85 > +++++++++++++++++++++++++++++++++++++++++++++++++++++ > cpus.c | 72 --------------------------------------------- > 2 files changed, 85 insertions(+), 72 deletions(-) > > diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c > index c59d5b0..78a0ab5 100644 > --- a/accel/tcg/tcg-all.c > +++ b/accel/tcg/tcg-all.c > @@ -30,6 +30,11 @@ > #include "cpu.h" > #include "sysemu/cpus.h" > #include "qemu/main-loop.h" > +#include "tcg/tcg.h" > +#include "include/qapi/error.h" > +#include "include/qemu/error-report.h" > +#include "include/hw/boards.h" > +#include "qemu/option.h" > > unsigned long tcg_tb_size; > > @@ -58,6 +63,55 @@ static void tcg_handle_interrupt(CPUState *cpu, int mask) > } > } > > +/* > + * We default to false if we know other options have been enabled > + * which are currently incompatible with MTTCG. Otherwise when each > + * guest (target) has been updated to support: > + * - atomic instructions > + * - memory ordering primitives (barriers) > + * they can set the appropriate CONFIG flags in ${target}-softmmu.mak > + * > + * Once a guest architecture has been converted to the new primitives > + * there are two remaining limitations to check. > + * > + * - The guest can't be oversized (e.g. 64 bit guest on 32 bit host) > + * - The host must have a stronger memory order than the guest > + * > + * It may be possible in future to support strong guests on weak hosts > + * but that will require tagging all load/stores in a guest with their > + * implicit memory order requirements which would likely slow things > + * down a lot. > + */ > + > +static bool check_tcg_memory_orders_compatible(void) > +{ > +#if defined(TCG_GUEST_DEFAULT_MO) && defined(TCG_TARGET_DEFAULT_MO) > + return (TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) == 0; > +#else > + return false; > +#endif > +} > + > +static bool default_mttcg_enabled(void) > +{ > + if (use_icount || TCG_OVERSIZED_GUEST) { > + return false; > + } else { > +#ifdef TARGET_SUPPORTS_MTTCG > + return check_tcg_memory_orders_compatible(); > +#else > + return false; > +#endif > + } > +} > + > +static void tcg_accel_instance_init(Object *obj) > +{ > + TCGState *s = TCG_STATE(obj);
It breaks compilation: accel/tcg/tcg-all.c:110:19: error: implicit declaration of function ‘TCG_STATE’ [-Werror=implicit-function-declaration] 110 | TCGState *s = TCG_STATE(obj); > + > + mttcg_enabled = default_mttcg_enabled(); > +} > + > static int tcg_init(MachineState *ms) > { > tcg_exec_init(tcg_tb_size * 1024 * 1024); > @@ -65,6 +119,36 @@ static int tcg_init(MachineState *ms) > return 0; > } > > +void qemu_tcg_configure(QemuOpts *opts, Error **errp) > +{ > + const char *t = qemu_opt_get(opts, "thread"); > + if (!t) { > + return; > + } > + if (strcmp(t, "multi") == 0) { > + if (TCG_OVERSIZED_GUEST) { > + error_setg(errp, "No MTTCG when guest word size > hosts"); > + } else if (use_icount) { > + error_setg(errp, "No MTTCG when icount is enabled"); > + } else { > +#ifndef TARGET_SUPPORTS_MTTCG > + warn_report("Guest not yet converted to MTTCG - " > + "you may get unexpected results"); > +#endif > + if (!check_tcg_memory_orders_compatible()) { > + warn_report("Guest expects a stronger memory ordering " > + "than the host provides"); > + error_printf("This may cause strange/hard to debug > errors\n"); > + } > + mttcg_enabled = true; > + } > + } else if (strcmp(t, "single") == 0) { > + mttcg_enabled = false; > + } else { > + error_setg(errp, "Invalid 'thread' setting %s", t); > + } > +} > + > static void tcg_accel_class_init(ObjectClass *oc, void *data) > { > AccelClass *ac = ACCEL_CLASS(oc); > @@ -78,6 +162,7 @@ static void tcg_accel_class_init(ObjectClass *oc, void > *data) > static const TypeInfo tcg_accel_type = { > .name = TYPE_TCG_ACCEL, > .parent = TYPE_ACCEL, > + .instance_init = tcg_accel_instance_init, > .class_init = tcg_accel_class_init, > }; > > diff --git a/cpus.c b/cpus.c > index 63bda15..b472378 100644 > --- a/cpus.c > +++ b/cpus.c > @@ -166,78 +166,6 @@ typedef struct TimersState { > static TimersState timers_state; > bool mttcg_enabled; > > -/* > - * We default to false if we know other options have been enabled > - * which are currently incompatible with MTTCG. Otherwise when each > - * guest (target) has been updated to support: > - * - atomic instructions > - * - memory ordering primitives (barriers) > - * they can set the appropriate CONFIG flags in ${target}-softmmu.mak > - * > - * Once a guest architecture has been converted to the new primitives > - * there are two remaining limitations to check. > - * > - * - The guest can't be oversized (e.g. 64 bit guest on 32 bit host) > - * - The host must have a stronger memory order than the guest > - * > - * It may be possible in future to support strong guests on weak hosts > - * but that will require tagging all load/stores in a guest with their > - * implicit memory order requirements which would likely slow things > - * down a lot. > - */ > - > -static bool check_tcg_memory_orders_compatible(void) > -{ > -#if defined(TCG_GUEST_DEFAULT_MO) && defined(TCG_TARGET_DEFAULT_MO) > - return (TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) == 0; > -#else > - return false; > -#endif > -} > - > -static bool default_mttcg_enabled(void) > -{ > - if (use_icount || TCG_OVERSIZED_GUEST) { > - return false; > - } else { > -#ifdef TARGET_SUPPORTS_MTTCG > - return check_tcg_memory_orders_compatible(); > -#else > - return false; > -#endif > - } > -} > - > -void qemu_tcg_configure(QemuOpts *opts, Error **errp) > -{ > - const char *t = qemu_opt_get(opts, "thread"); > - if (t) { > - if (strcmp(t, "multi") == 0) { > - if (TCG_OVERSIZED_GUEST) { > - error_setg(errp, "No MTTCG when guest word size > hosts"); > - } else if (use_icount) { > - error_setg(errp, "No MTTCG when icount is enabled"); > - } else { > -#ifndef TARGET_SUPPORTS_MTTCG > - warn_report("Guest not yet converted to MTTCG - " > - "you may get unexpected results"); > -#endif > - if (!check_tcg_memory_orders_compatible()) { > - warn_report("Guest expects a stronger memory ordering " > - "than the host provides"); > - error_printf("This may cause strange/hard to debug > errors\n"); > - } > - mttcg_enabled = true; > - } > - } else if (strcmp(t, "single") == 0) { > - mttcg_enabled = false; > - } else { > - error_setg(errp, "Invalid 'thread' setting %s", t); > - } > - } else { > - mttcg_enabled = default_mttcg_enabled(); > - } > -} > > /* The current number of executed instructions is based on what we > * originally budgeted minus the current state of the decrementing > -- > 1.8.3.1 > > > -- Marc-André Lureau