exec: Set cpu_index only if it's not been explictly set

It keeps the legacy behavior for all users that doesn't care
about stable cpu_index value, but would allow boards that
would support device_add/device_del to set stable cpu_index
that won't depend on order in which cpus are created/destroyed.

While at that simplify cpu_get_free_index() as cpu_index
generated by USER_ONLY and softmmu variants is the same
since none of the users support cpu-remove so far, except
of not yet released spapr/x86 device_add/delr, which
will be altered by follow up patches to set stable
cpu_index manually.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This commit is contained in:
Igor Mammedov 2016-07-25 11:59:21 +02:00 committed by Eduardo Habkost
parent 8b1b835035
commit a07f953ef4
3 changed files with 9 additions and 39 deletions

44
exec.c
View file

@ -598,30 +598,7 @@ AddressSpace *cpu_get_address_space(CPUState *cpu, int asidx)
}
#endif
#ifndef CONFIG_USER_ONLY
static DECLARE_BITMAP(cpu_index_map, MAX_CPUMASK_BITS);
static int cpu_get_free_index(Error **errp)
{
int cpu = find_first_zero_bit(cpu_index_map, MAX_CPUMASK_BITS);
if (cpu >= MAX_CPUMASK_BITS) {
error_setg(errp, "Trying to use more CPUs than max of %d",
MAX_CPUMASK_BITS);
return -1;
}
bitmap_set(cpu_index_map, cpu, 1);
return cpu;
}
static void cpu_release_index(CPUState *cpu)
{
bitmap_clear(cpu_index_map, cpu->cpu_index, 1);
}
#else
static int cpu_get_free_index(Error **errp)
static int cpu_get_free_index(void)
{
CPUState *some_cpu;
int cpu_index = 0;
@ -632,12 +609,6 @@ static int cpu_get_free_index(Error **errp)
return cpu_index;
}
static void cpu_release_index(CPUState *cpu)
{
return;
}
#endif
void cpu_exec_exit(CPUState *cpu)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
@ -651,8 +622,7 @@ void cpu_exec_exit(CPUState *cpu)
QTAILQ_REMOVE(&cpus, cpu, node);
cpu->node.tqe_prev = NULL;
cpu_release_index(cpu);
cpu->cpu_index = -1;
cpu->cpu_index = UNASSIGNED_CPU_INDEX;
cpu_list_unlock();
if (cc->vmsd != NULL) {
@ -666,7 +636,7 @@ void cpu_exec_exit(CPUState *cpu)
void cpu_exec_init(CPUState *cpu, Error **errp)
{
CPUClass *cc ATTRIBUTE_UNUSED = CPU_GET_CLASS(cpu);
Error *local_err = NULL;
Error *local_err ATTRIBUTE_UNUSED = NULL;
cpu->as = NULL;
cpu->num_ases = 0;
@ -690,11 +660,9 @@ void cpu_exec_init(CPUState *cpu, Error **errp)
#endif
cpu_list_lock();
cpu->cpu_index = cpu_get_free_index(&local_err);
if (local_err) {
error_propagate(errp, local_err);
cpu_list_unlock();
return;
if (cpu->cpu_index == UNASSIGNED_CPU_INDEX) {
cpu->cpu_index = cpu_get_free_index();
assert(cpu->cpu_index != UNASSIGNED_CPU_INDEX);
}
QTAILQ_INSERT_TAIL(&cpus, cpu, node);
cpu_list_unlock();

View file

@ -883,4 +883,6 @@ extern const struct VMStateDescription vmstate_cpu_common;
.offset = 0, \
}
#define UNASSIGNED_CPU_INDEX -1
#endif

View file

@ -340,7 +340,7 @@ static void cpu_common_initfn(Object *obj)
CPUState *cpu = CPU(obj);
CPUClass *cc = CPU_GET_CLASS(obj);
cpu->cpu_index = -1;
cpu->cpu_index = UNASSIGNED_CPU_INDEX;
cpu->gdb_num_regs = cpu->gdb_num_g_regs = cc->gdb_num_core_regs;
qemu_mutex_init(&cpu->work_mutex);
QTAILQ_INIT(&cpu->breakpoints);