unicorn/qemu/qom/cpu.c
Bharata B Rao 309b85548f
cpu: Convert cpu_index into a bitmap
Currently CPUState::cpu_index is monotonically increasing and a newly
created CPU always gets the next higher index. The next available
index is calculated by counting the existing number of CPUs. This is
fine as long as we only add CPUs, but there are architectures which
are starting to support CPU removal, too. For an architecture like PowerPC
which derives its CPU identifier (device tree ID) from cpu_index, the
existing logic of generating cpu_index values causes problems.

With the currently proposed method of handling vCPU removal by parking
the vCPU fd in QEMU
(Ref: http://lists.gnu.org/archive/html/qemu-devel/2015-02/msg02604.html),
generating cpu_index this way will not work for PowerPC.

This patch changes the way cpu_index is handed out by maintaining
a bit map of the CPUs that tracks both addition and removal of CPUs.

The CPU bitmap allocation logic is part of cpu_exec_init(), which is
called by instance_init routines of various CPU targets. Newly added
cpu_exec_exit() API handles the deallocation part and this routine is
called from generic CPU instance_finalize.

Note: This new CPU enumeration is for !CONFIG_USER_ONLY only.
CONFIG_USER_ONLY continues to have the old enumeration logic.

Backports commit b7bca7333411bd19c449147e8202ae6b0e4a8e09 from qemu
2018-03-21 08:06:07 -04:00

332 lines
8.5 KiB
C

/*
* QEMU CPU model
*
* Copyright (c) 2012-2014 SUSE LINUX Products GmbH
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see
* <http://www.gnu.org/licenses/gpl-2.0.html>
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "hw/boards.h"
#include "qemu/log.h"
#include "uc_priv.h"
CPUState *cpu_by_arch_id(struct uc_struct *uc, int64_t id)
{
CPUState *cpu = uc->cpu;
CPUClass *cc = CPU_GET_CLASS(uc, cpu);
if (cc->get_arch_id(cpu) == id) {
return cpu;
}
return NULL;
}
bool cpu_exists(struct uc_struct *uc, int64_t id)
{
return !!cpu_by_arch_id(uc, id);
}
CPUState *cpu_create(struct uc_struct *uc, const char *typename)
{
Error *err = NULL;
CPUState *cpu = CPU(object_new(uc, typename));
object_property_set_bool(uc, OBJECT(cpu), true, "realized", &err);
if (err != NULL) {
object_unref(uc, OBJECT(cpu));
return NULL;
}
return cpu;
}
bool cpu_paging_enabled(const CPUState *cpu)
{
CPUClass *cc = CPU_GET_CLASS(cpu->uc, cpu);
return cc->get_paging_enabled(cpu);
}
static bool cpu_common_get_paging_enabled(const CPUState *cpu)
{
return false;
}
void cpu_get_memory_mapping(CPUState *cpu, MemoryMappingList *list,
Error **errp)
{
CPUClass *cc = CPU_GET_CLASS(cpu->uc, cpu);
cc->get_memory_mapping(cpu, list, errp);
}
static void cpu_common_get_memory_mapping(CPUState *cpu,
MemoryMappingList *list,
Error **errp)
{
error_setg(errp, "Obtaining memory mappings is unsupported on this CPU.");
}
void cpu_reset_interrupt(CPUState *cpu, int mask)
{
cpu->interrupt_request &= ~mask;
}
void cpu_exit(CPUState *cpu)
{
atomic_set(&cpu->exit_request, 1);
/* Ensure cpu_exec will see the exit request after TCG has exited. */
smp_wmb();
atomic_set(&cpu->tcg_exit_req, 1);
}
static void cpu_common_noop(CPUState *cpu)
{
}
static bool cpu_common_exec_interrupt(CPUState *cpu, int int_req)
{
return false;
}
void cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
int flags)
{
CPUClass *cc = CPU_GET_CLASS(cpu->uc, cpu);
if (cc->dump_state) {
cc->dump_state(cpu, f, cpu_fprintf, flags);
}
}
void cpu_dump_statistics(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
int flags)
{
CPUClass *cc = CPU_GET_CLASS(cpu->uc, cpu);
if (cc->dump_statistics) {
cc->dump_statistics(cpu, f, cpu_fprintf, flags);
}
}
void cpu_reset(CPUState *cpu)
{
CPUClass *klass = CPU_GET_CLASS(cpu->uc, cpu);
if (klass->reset != NULL) {
(*klass->reset)(cpu);
}
}
static void cpu_common_reset(CPUState *cpu)
{
CPUClass *cc = CPU_GET_CLASS(cpu->uc, cpu);
if (qemu_loglevel_mask(CPU_LOG_RESET)) {
qemu_log("CPU Reset (CPU %d)\n", cpu->cpu_index);
log_cpu_state(cpu, cc->reset_dump_flags);
}
cpu->interrupt_request = 0;
cpu->halted = 0;
cpu->mem_io_pc = 0;
cpu->mem_io_vaddr = 0;
cpu->icount_extra = 0;
cpu->icount_decr.u32 = 0;
cpu->can_do_io = 0;
cpu->exception_index = -1;
cpu->crash_occurred = false;
// TODO: Should be uncommented, but good 'ol
// unicorn's crappy symbol deduplication
// makes it impossible right now
//if (tcg_enabled(cpu->uc)) {
cpu_tb_jmp_cache_clear(cpu);
// Ditto: should also be uncommented
//tcg_flush_softmmu_tlb(cpu);
//}
}
static bool cpu_common_has_work(CPUState *cs)
{
return false;
}
static bool cpu_common_debug_check_watchpoint(CPUState *cpu, CPUWatchpoint *wp)
{
/* If no extra check is required, QEMU watchpoint match can be considered
* as an architectural match.
*/
return true;
}
ObjectClass *cpu_class_by_name(struct uc_struct *uc, const char *typename, const char *cpu_model)
{
CPUClass *cc = CPU_CLASS(uc, object_class_by_name(uc, typename));
assert(cpu_model && cc->class_by_name);
return cc->class_by_name(uc, cpu_model);
}
static ObjectClass *cpu_common_class_by_name(struct uc_struct *uc, const char *cpu_model)
{
return NULL;
}
static void cpu_common_parse_features(struct uc_struct *uc, const char *typename, char *features,
Error **errp)
{
char *val;
/* Single "key=value" string being parsed */
char *featurestr = features ? strtok(features, ",") : NULL;
/* should be called only once, catch invalid users */
assert(!uc->cpu_globals_initialized);
if (uc->cpu_globals_initialized) {
return;
}
uc->cpu_globals_initialized = true;
while (featurestr) {
val = strchr(featurestr, '=');
if (val) {
// Unicorn: if'd out
#if 0
GlobalProperty *prop = g_new0(GlobalProperty, 1);
#endif
*val = 0;
val++;
// Unicorn: If'd out
#if 0
prop->driver = typename;
prop->property = g_strdup(featurestr);
prop->value = g_strdup(val);
prop->errp = &error_fatal;
qdev_prop_register_global(prop);
#endif
} else {
error_setg(errp, "Expected key=value format, found %s.",
featurestr);
return;
}
featurestr = strtok(NULL, ",");
}
}
static int cpu_common_realizefn(struct uc_struct *uc, DeviceState *dev, Error **errp)
{
CPUState *cpu = CPU(dev);
Object *machine = qdev_get_machine(uc);
/* qdev_get_machine() can return something that's not TYPE_MACHINE
* if this is one of the user-only emulators; in that case there's
* no need to check the ignore_memory_transaction_failures board flag.
*/
if (object_dynamic_cast(uc, machine, TYPE_MACHINE)) {
ObjectClass *oc = object_get_class(machine);
MachineClass *mc = MACHINE_CLASS(uc, oc);
if (mc) {
cpu->ignore_memory_transaction_failures =
mc->ignore_memory_transaction_failures;
}
}
if (dev->hotplugged) {
cpu_resume(cpu);
}
return 0;
}
static void cpu_common_initfn(struct uc_struct *uc, Object *obj, void *opaque)
{
CPUState *cpu = CPU(obj);
cpu->cpu_index = -1;
QTAILQ_INIT(&cpu->breakpoints);
QTAILQ_INIT(&cpu->watchpoints);
}
static void cpu_common_finalize(struct uc_struct *uc, Object *obj, void *opaque)
{
uc->cpu_exec_exit(CPU(obj));
}
static int64_t cpu_common_get_arch_id(CPUState *cpu)
{
return cpu->cpu_index;
}
static vaddr cpu_adjust_watchpoint_address(CPUState *cpu, vaddr addr, int len)
{
return addr;
}
static void cpu_class_init(struct uc_struct *uc, ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(uc, klass);
CPUClass *k = CPU_CLASS(uc, klass);
k->class_by_name = cpu_common_class_by_name;
k->parse_features = cpu_common_parse_features;
k->reset = cpu_common_reset;
k->get_arch_id = cpu_common_get_arch_id;
k->has_work = cpu_common_has_work;
k->get_paging_enabled = cpu_common_get_paging_enabled;
k->get_memory_mapping = cpu_common_get_memory_mapping;
k->debug_excp_handler = cpu_common_noop;
k->debug_check_watchpoint = cpu_common_debug_check_watchpoint;
k->cpu_exec_enter = cpu_common_noop;
k->cpu_exec_exit = cpu_common_noop;
k->cpu_exec_interrupt = cpu_common_exec_interrupt;
k->adjust_watchpoint_address = cpu_adjust_watchpoint_address;
dc->realize = cpu_common_realizefn;
/*
* Reason: CPUs still need special care by board code: wiring up
* IRQs, adding reset handlers, halting non-first CPUs, ...
*/
dc->cannot_instantiate_with_device_add_yet = true;
}
static const TypeInfo cpu_type_info = {
TYPE_CPU,
TYPE_DEVICE,
sizeof(CPUClass),
sizeof(CPUState),
NULL,
cpu_common_initfn,
NULL,
cpu_common_finalize,
NULL,
cpu_class_init,
NULL,
NULL,
true,
};
void cpu_register_types(struct uc_struct *uc)
{
type_register_static(uc, &cpu_type_info);
}