qemu/qom/cpu.c
Bharata B Rao b7bca73334 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.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
[AF: max_cpus -> MAX_CPUMASK_BITS]
Signed-off-by: Andreas Färber <afaerber@suse.de>
2015-07-09 15:20:40 +02:00

379 lines
9.4 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-common.h"
#include "qom/cpu.h"
#include "sysemu/kvm.h"
#include "qemu/notify.h"
#include "qemu/log.h"
#include "qemu/error-report.h"
#include "sysemu/sysemu.h"
bool cpu_exists(int64_t id)
{
CPUState *cpu;
CPU_FOREACH(cpu) {
CPUClass *cc = CPU_GET_CLASS(cpu);
if (cc->get_arch_id(cpu) == id) {
return true;
}
}
return false;
}
CPUState *cpu_generic_init(const char *typename, const char *cpu_model)
{
char *str, *name, *featurestr;
CPUState *cpu;
ObjectClass *oc;
CPUClass *cc;
Error *err = NULL;
str = g_strdup(cpu_model);
name = strtok(str, ",");
oc = cpu_class_by_name(typename, name);
if (oc == NULL) {
g_free(str);
return NULL;
}
cpu = CPU(object_new(object_class_get_name(oc)));
cc = CPU_GET_CLASS(cpu);
featurestr = strtok(NULL, ",");
cc->parse_features(cpu, featurestr, &err);
g_free(str);
if (err != NULL) {
goto out;
}
object_property_set_bool(OBJECT(cpu), true, "realized", &err);
out:
if (err != NULL) {
error_report_err(err);
object_unref(OBJECT(cpu));
return NULL;
}
return cpu;
}
bool cpu_paging_enabled(const CPUState *cpu)
{
CPUClass *cc = CPU_GET_CLASS(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);
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)
{
cpu->exit_request = 1;
cpu->tcg_exit_req = 1;
}
int cpu_write_elf32_qemunote(WriteCoreDumpFunction f, CPUState *cpu,
void *opaque)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
return (*cc->write_elf32_qemunote)(f, cpu, opaque);
}
static int cpu_common_write_elf32_qemunote(WriteCoreDumpFunction f,
CPUState *cpu, void *opaque)
{
return -1;
}
int cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cpu,
int cpuid, void *opaque)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
return (*cc->write_elf32_note)(f, cpu, cpuid, opaque);
}
static int cpu_common_write_elf32_note(WriteCoreDumpFunction f,
CPUState *cpu, int cpuid,
void *opaque)
{
return -1;
}
int cpu_write_elf64_qemunote(WriteCoreDumpFunction f, CPUState *cpu,
void *opaque)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
return (*cc->write_elf64_qemunote)(f, cpu, opaque);
}
static int cpu_common_write_elf64_qemunote(WriteCoreDumpFunction f,
CPUState *cpu, void *opaque)
{
return -1;
}
int cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cpu,
int cpuid, void *opaque)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
return (*cc->write_elf64_note)(f, cpu, cpuid, opaque);
}
static int cpu_common_write_elf64_note(WriteCoreDumpFunction f,
CPUState *cpu, int cpuid,
void *opaque)
{
return -1;
}
static int cpu_common_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg)
{
return 0;
}
static int cpu_common_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg)
{
return 0;
}
bool target_words_bigendian(void);
static bool cpu_common_virtio_is_big_endian(CPUState *cpu)
{
return target_words_bigendian();
}
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);
if (cc->dump_state) {
cpu_synchronize_state(cpu);
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);
if (cc->dump_statistics) {
cc->dump_statistics(cpu, f, cpu_fprintf, flags);
}
}
void cpu_reset(CPUState *cpu)
{
CPUClass *klass = CPU_GET_CLASS(cpu);
if (klass->reset != NULL) {
(*klass->reset)(cpu);
}
}
static void cpu_common_reset(CPUState *cpu)
{
CPUClass *cc = CPU_GET_CLASS(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->current_tb = NULL;
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;
memset(cpu->tb_jmp_cache, 0, TB_JMP_CACHE_SIZE * sizeof(void *));
}
static bool cpu_common_has_work(CPUState *cs)
{
return false;
}
ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model)
{
CPUClass *cc = CPU_CLASS(object_class_by_name(typename));
return cc->class_by_name(cpu_model);
}
static ObjectClass *cpu_common_class_by_name(const char *cpu_model)
{
return NULL;
}
static void cpu_common_parse_features(CPUState *cpu, char *features,
Error **errp)
{
char *featurestr; /* Single "key=value" string being parsed */
char *val;
Error *err = NULL;
featurestr = features ? strtok(features, ",") : NULL;
while (featurestr) {
val = strchr(featurestr, '=');
if (val) {
*val = 0;
val++;
object_property_parse(OBJECT(cpu), val, featurestr, &err);
if (err) {
error_propagate(errp, err);
return;
}
} else {
error_setg(errp, "Expected key=value format, found %s.",
featurestr);
return;
}
featurestr = strtok(NULL, ",");
}
}
static void cpu_common_realizefn(DeviceState *dev, Error **errp)
{
CPUState *cpu = CPU(dev);
if (dev->hotplugged) {
cpu_synchronize_post_init(cpu);
cpu_resume(cpu);
}
}
static void cpu_common_initfn(Object *obj)
{
CPUState *cpu = CPU(obj);
CPUClass *cc = CPU_GET_CLASS(obj);
cpu->cpu_index = -1;
cpu->gdb_num_regs = cpu->gdb_num_g_regs = cc->gdb_num_core_regs;
QTAILQ_INIT(&cpu->breakpoints);
QTAILQ_INIT(&cpu->watchpoints);
}
static void cpu_common_finalize(Object *obj)
{
cpu_exec_exit(CPU(obj));
}
static int64_t cpu_common_get_arch_id(CPUState *cpu)
{
return cpu->cpu_index;
}
static void cpu_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
CPUClass *k = CPU_CLASS(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->write_elf32_qemunote = cpu_common_write_elf32_qemunote;
k->write_elf32_note = cpu_common_write_elf32_note;
k->write_elf64_qemunote = cpu_common_write_elf64_qemunote;
k->write_elf64_note = cpu_common_write_elf64_note;
k->gdb_read_register = cpu_common_gdb_read_register;
k->gdb_write_register = cpu_common_gdb_write_register;
k->virtio_is_big_endian = cpu_common_virtio_is_big_endian;
k->debug_excp_handler = cpu_common_noop;
k->cpu_exec_enter = cpu_common_noop;
k->cpu_exec_exit = cpu_common_noop;
k->cpu_exec_interrupt = cpu_common_exec_interrupt;
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 = {
.name = TYPE_CPU,
.parent = TYPE_DEVICE,
.instance_size = sizeof(CPUState),
.instance_init = cpu_common_initfn,
.instance_finalize = cpu_common_finalize,
.abstract = true,
.class_size = sizeof(CPUClass),
.class_init = cpu_class_init,
};
static void cpu_register_types(void)
{
type_register_static(&cpu_type_info);
}
type_init(cpu_register_types)