/*
* QEMU System Emulator, accelerator interfaces
*
* Copyright (c) 2003-2008 Fabrice Bellard
* Copyright (c) 2014 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "sysemu/tcg.h"
#include "sysemu/cpu-timers.h"
#include "tcg/tcg.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "hw/boards.h"
#include "qapi/qapi-builtin-visit.h"
#include "tcg-cpus.h"
struct TCGState {
AccelState parent_obj;
bool mttcg_enabled;
unsigned long tb_size;
};
typedef struct TCGState TCGState;
#define TYPE_TCG_ACCEL ACCEL_CLASS_NAME("tcg")
DECLARE_INSTANCE_CHECKER(TCGState, TCG_STATE,
TYPE_TCG_ACCEL)
/*
* 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 (icount_enabled() || 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);
s->mttcg_enabled = default_mttcg_enabled();
}
bool mttcg_enabled;
static int tcg_init(MachineState *ms)
{
TCGState *s = TCG_STATE(current_accel());
tcg_exec_init(s->tb_size * 1024 * 1024);
mttcg_enabled = s->mttcg_enabled;
/*
* Initialize TCG regions
*/
tcg_region_init();
if (mttcg_enabled) {
cpus_register_accel(&tcg_cpus_mttcg);
} else if (icount_enabled()) {
cpus_register_accel(&tcg_cpus_icount);
} else {
cpus_register_accel(&tcg_cpus_rr);
}
return 0;
}
static char *tcg_get_thread(Object *obj, Error **errp)
{
TCGState *s = TCG_STATE(obj);
return g_strdup(s->mttcg_enabled ? "multi" : "single");
}
static void tcg_set_thread(Object *obj, const char *value, Error **errp)
{
TCGState *s = TCG_STATE(obj);
if (strcmp(value, "multi") == 0) {
if (TCG_OVERSIZED_GUEST) {
error_setg(errp, "No MTTCG when guest word size > hosts");
} else if (icount_enabled()) {
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");
}
s->mttcg_enabled = true;
}
} else if (strcmp(value, "single") == 0) {
s->mttcg_enabled = false;
} else {
error_setg(errp, "Invalid 'thread' setting %s", value);
}
}
static void tcg_get_tb_size(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
TCGState *s = TCG_STATE(obj);
uint32_t value = s->tb_size;
visit_type_uint32(v, name, &value, errp);
}
static void tcg_set_tb_size(Object *obj, Visitor *v,
const char *name, void *opaque,
Error **errp)
{
TCGState *s = TCG_STATE(obj);
uint32_t value;
if (!visit_type_uint32(v, name, &value, errp)) {
return;
}
s->tb_size = value;
}
static void tcg_accel_class_init(ObjectClass *oc, void *data)
{
AccelClass *ac = ACCEL_CLASS(oc);
ac->name = "tcg";
ac->init_machine = tcg_init;
ac->allowed = &tcg_allowed;
object_class_property_add_str(oc, "thread",
tcg_get_thread,
tcg_set_thread);
object_class_property_add(oc, "tb-size", "int",
tcg_get_tb_size, tcg_set_tb_size,
NULL, NULL);
object_class_property_set_description(oc, "tb-size",
"TCG translation block cache size");
}
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,
.instance_size = sizeof(TCGState),
};
static void register_accel_types(void)
{
type_register_static(&tcg_accel_type);
}
type_init(register_accel_types);
