qemu/backends/hostmem.c

373 lines
11 KiB
C

/*
* QEMU Host Memory Backend
*
* Copyright (C) 2013-2014 Red Hat Inc
*
* Authors:
* Igor Mammedov <imammedo@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "sysemu/hostmem.h"
#include "hw/boards.h"
#include "qapi/visitor.h"
#include "qapi-types.h"
#include "qapi-visit.h"
#include "qemu/config-file.h"
#include "qom/object_interfaces.h"
#ifdef CONFIG_NUMA
#include <numaif.h>
QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_DEFAULT != MPOL_DEFAULT);
QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_PREFERRED != MPOL_PREFERRED);
QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_BIND != MPOL_BIND);
QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_INTERLEAVE != MPOL_INTERLEAVE);
#endif
static void
host_memory_backend_get_size(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
uint64_t value = backend->size;
visit_type_size(v, &value, name, errp);
}
static void
host_memory_backend_set_size(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
Error *local_err = NULL;
uint64_t value;
if (memory_region_size(&backend->mr)) {
error_setg(&local_err, "cannot change property value");
goto out;
}
visit_type_size(v, &value, name, &local_err);
if (local_err) {
goto out;
}
if (!value) {
error_setg(&local_err, "Property '%s.%s' doesn't take value '%"
PRIu64 "'", object_get_typename(obj), name, value);
goto out;
}
backend->size = value;
out:
error_propagate(errp, local_err);
}
static void
host_memory_backend_get_host_nodes(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
uint16List *host_nodes = NULL;
uint16List **node = &host_nodes;
unsigned long value;
value = find_first_bit(backend->host_nodes, MAX_NODES);
if (value == MAX_NODES) {
return;
}
*node = g_malloc0(sizeof(**node));
(*node)->value = value;
node = &(*node)->next;
do {
value = find_next_bit(backend->host_nodes, MAX_NODES, value + 1);
if (value == MAX_NODES) {
break;
}
*node = g_malloc0(sizeof(**node));
(*node)->value = value;
node = &(*node)->next;
} while (true);
visit_type_uint16List(v, &host_nodes, name, errp);
}
static void
host_memory_backend_set_host_nodes(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)
{
#ifdef CONFIG_NUMA
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
uint16List *l = NULL;
visit_type_uint16List(v, &l, name, errp);
while (l) {
bitmap_set(backend->host_nodes, l->value, 1);
l = l->next;
}
#else
error_setg(errp, "NUMA node binding are not supported by this QEMU");
#endif
}
static int
host_memory_backend_get_policy(Object *obj, Error **errp G_GNUC_UNUSED)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
return backend->policy;
}
static void
host_memory_backend_set_policy(Object *obj, int policy, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
backend->policy = policy;
#ifndef CONFIG_NUMA
if (policy != HOST_MEM_POLICY_DEFAULT) {
error_setg(errp, "NUMA policies are not supported by this QEMU");
}
#endif
}
static bool host_memory_backend_get_merge(Object *obj, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
return backend->merge;
}
static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
if (!memory_region_size(&backend->mr)) {
backend->merge = value;
return;
}
if (value != backend->merge) {
void *ptr = memory_region_get_ram_ptr(&backend->mr);
uint64_t sz = memory_region_size(&backend->mr);
qemu_madvise(ptr, sz,
value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE);
backend->merge = value;
}
}
static bool host_memory_backend_get_dump(Object *obj, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
return backend->dump;
}
static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
if (!memory_region_size(&backend->mr)) {
backend->dump = value;
return;
}
if (value != backend->dump) {
void *ptr = memory_region_get_ram_ptr(&backend->mr);
uint64_t sz = memory_region_size(&backend->mr);
qemu_madvise(ptr, sz,
value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP);
backend->dump = value;
}
}
static bool host_memory_backend_get_prealloc(Object *obj, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
return backend->prealloc || backend->force_prealloc;
}
static void host_memory_backend_set_prealloc(Object *obj, bool value,
Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
if (backend->force_prealloc) {
if (value) {
error_setg(errp,
"remove -mem-prealloc to use the prealloc property");
return;
}
}
if (!memory_region_size(&backend->mr)) {
backend->prealloc = value;
return;
}
if (value && !backend->prealloc) {
int fd = memory_region_get_fd(&backend->mr);
void *ptr = memory_region_get_ram_ptr(&backend->mr);
uint64_t sz = memory_region_size(&backend->mr);
os_mem_prealloc(fd, ptr, sz);
backend->prealloc = true;
}
}
static void host_memory_backend_init(Object *obj)
{
HostMemoryBackend *backend = MEMORY_BACKEND(obj);
MachineState *machine = MACHINE(qdev_get_machine());
backend->merge = machine_mem_merge(machine);
backend->dump = machine_dump_guest_core(machine);
backend->prealloc = mem_prealloc;
object_property_add_bool(obj, "merge",
host_memory_backend_get_merge,
host_memory_backend_set_merge, NULL);
object_property_add_bool(obj, "dump",
host_memory_backend_get_dump,
host_memory_backend_set_dump, NULL);
object_property_add_bool(obj, "prealloc",
host_memory_backend_get_prealloc,
host_memory_backend_set_prealloc, NULL);
object_property_add(obj, "size", "int",
host_memory_backend_get_size,
host_memory_backend_set_size, NULL, NULL, NULL);
object_property_add(obj, "host-nodes", "int",
host_memory_backend_get_host_nodes,
host_memory_backend_set_host_nodes, NULL, NULL, NULL);
object_property_add_enum(obj, "policy", "HostMemPolicy",
HostMemPolicy_lookup,
host_memory_backend_get_policy,
host_memory_backend_set_policy, NULL);
}
MemoryRegion *
host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp)
{
return memory_region_size(&backend->mr) ? &backend->mr : NULL;
}
static void
host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
{
HostMemoryBackend *backend = MEMORY_BACKEND(uc);
HostMemoryBackendClass *bc = MEMORY_BACKEND_GET_CLASS(uc);
Error *local_err = NULL;
void *ptr;
uint64_t sz;
if (bc->alloc) {
bc->alloc(backend, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
ptr = memory_region_get_ram_ptr(&backend->mr);
sz = memory_region_size(&backend->mr);
if (backend->merge) {
qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE);
}
if (!backend->dump) {
qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP);
}
#ifdef CONFIG_NUMA
unsigned long lastbit = find_last_bit(backend->host_nodes, MAX_NODES);
/* lastbit == MAX_NODES means maxnode = 0 */
unsigned long maxnode = (lastbit + 1) % (MAX_NODES + 1);
/* ensure policy won't be ignored in case memory is preallocated
* before mbind(). note: MPOL_MF_STRICT is ignored on hugepages so
* this doesn't catch hugepage case. */
unsigned flags = MPOL_MF_STRICT | MPOL_MF_MOVE;
/* check for invalid host-nodes and policies and give more verbose
* error messages than mbind(). */
if (maxnode && backend->policy == MPOL_DEFAULT) {
error_setg(errp, "host-nodes must be empty for policy default,"
" or you should explicitly specify a policy other"
" than default");
return;
} else if (maxnode == 0 && backend->policy != MPOL_DEFAULT) {
error_setg(errp, "host-nodes must be set for policy %s",
HostMemPolicy_lookup[backend->policy]);
return;
}
/* We can have up to MAX_NODES nodes, but we need to pass maxnode+1
* as argument to mbind() due to an old Linux bug (feature?) which
* cuts off the last specified node. This means backend->host_nodes
* must have MAX_NODES+1 bits available.
*/
assert(sizeof(backend->host_nodes) >=
BITS_TO_LONGS(MAX_NODES + 1) * sizeof(unsigned long));
assert(maxnode <= MAX_NODES);
if (mbind(ptr, sz, backend->policy,
maxnode ? backend->host_nodes : NULL, maxnode + 1, flags)) {
error_setg_errno(errp, errno,
"cannot bind memory to host NUMA nodes");
return;
}
#endif
/* Preallocate memory after the NUMA policy has been instantiated.
* This is necessary to guarantee memory is allocated with
* specified NUMA policy in place.
*/
if (backend->prealloc) {
os_mem_prealloc(memory_region_get_fd(&backend->mr), ptr, sz);
}
}
}
static bool
host_memory_backend_can_be_deleted(UserCreatable *uc, Error **errp)
{
MemoryRegion *mr;
mr = host_memory_backend_get_memory(MEMORY_BACKEND(uc), errp);
if (memory_region_is_mapped(mr)) {
return false;
} else {
return true;
}
}
static void
host_memory_backend_class_init(ObjectClass *oc, void *data)
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
ucc->complete = host_memory_backend_memory_complete;
ucc->can_be_deleted = host_memory_backend_can_be_deleted;
}
static const TypeInfo host_memory_backend_info = {
.name = TYPE_MEMORY_BACKEND,
.parent = TYPE_OBJECT,
.abstract = true,
.class_size = sizeof(HostMemoryBackendClass),
.class_init = host_memory_backend_class_init,
.instance_size = sizeof(HostMemoryBackend),
.instance_init = host_memory_backend_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void register_types(void)
{
type_register_static(&host_memory_backend_info);
}
type_init(register_types);