qemu-e2k/hw/core/numa.c
Igor Mammedov cdf8036520 numa: deprecate 'mem' parameter of '-numa node' option
The parameter allows to configure fake NUMA topology where guest
VM simulates NUMA topology but not actually getting performance
benefits from it. The same or better results could be achieved
using 'memdev' parameter.
Beside of unpredictable performance, '-numa node.mem' option has
other issues when it's used with combination of -mem-path +
+ -mem-prealloc + memdev backends (pc-dimm), breaking binding of
memdev backends since mem-path/mem-prealloc are global and affect
the most of RAM allocations.

It's possible to make memdevs and global -mem-path/mem-prealloc
to play nicely together but that will just complicate already
complicated code and add unobious ways it could break on 2
different memmory allocation pathes and their combinations.

Instead of it, consolidate all guest RAM allocation over memdev
which still allows to create fake NUMA configurations if desired
and leaves one simplifyed code path to consider when it comes
to guest RAM allocation.

To achieve desired simplification deprecate 'mem' parameter as its
ad-hoc partitioning of initial RAM MemoryRegion can't be translated
to memdev based backend transparently to users and in compatible
manner (migration wise).

Later down the road that will allow to consolidate means of how
guest RAM is allocated and would permit us to clean up quite
a bit memory allocations and numa code, leaving only 'memdev'
implementation in place.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1559205199-233510-3-git-send-email-imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-07-05 17:08:03 -03:00

609 lines
19 KiB
C

/*
* NUMA parameter parsing routines
*
* Copyright (c) 2014 Fujitsu Ltd.
*
* 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 "sysemu/numa.h"
#include "exec/cpu-common.h"
#include "exec/ramlist.h"
#include "qemu/bitmap.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "qapi/opts-visitor.h"
#include "qapi/qapi-visit-machine.h"
#include "hw/mem/pc-dimm.h"
#include "hw/mem/memory-device.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qemu/cutils.h"
QemuOptsList qemu_numa_opts = {
.name = "numa",
.implied_opt_name = "type",
.head = QTAILQ_HEAD_INITIALIZER(qemu_numa_opts.head),
.desc = { { 0 } } /* validated with OptsVisitor */
};
static int have_memdevs = -1;
static int max_numa_nodeid; /* Highest specified NUMA node ID, plus one.
* For all nodes, nodeid < max_numa_nodeid
*/
int nb_numa_nodes;
bool have_numa_distance;
NodeInfo numa_info[MAX_NODES];
static void parse_numa_node(MachineState *ms, NumaNodeOptions *node,
Error **errp)
{
Error *err = NULL;
uint16_t nodenr;
uint16List *cpus = NULL;
MachineClass *mc = MACHINE_GET_CLASS(ms);
unsigned int max_cpus = ms->smp.max_cpus;
if (node->has_nodeid) {
nodenr = node->nodeid;
} else {
nodenr = nb_numa_nodes;
}
if (nodenr >= MAX_NODES) {
error_setg(errp, "Max number of NUMA nodes reached: %"
PRIu16 "", nodenr);
return;
}
if (numa_info[nodenr].present) {
error_setg(errp, "Duplicate NUMA nodeid: %" PRIu16, nodenr);
return;
}
if (!mc->cpu_index_to_instance_props || !mc->get_default_cpu_node_id) {
error_setg(errp, "NUMA is not supported by this machine-type");
return;
}
for (cpus = node->cpus; cpus; cpus = cpus->next) {
CpuInstanceProperties props;
if (cpus->value >= max_cpus) {
error_setg(errp,
"CPU index (%" PRIu16 ")"
" should be smaller than maxcpus (%d)",
cpus->value, max_cpus);
return;
}
props = mc->cpu_index_to_instance_props(ms, cpus->value);
props.node_id = nodenr;
props.has_node_id = true;
machine_set_cpu_numa_node(ms, &props, &err);
if (err) {
error_propagate(errp, err);
return;
}
}
if (node->has_mem && node->has_memdev) {
error_setg(errp, "cannot specify both mem= and memdev=");
return;
}
if (have_memdevs == -1) {
have_memdevs = node->has_memdev;
}
if (node->has_memdev != have_memdevs) {
error_setg(errp, "memdev option must be specified for either "
"all or no nodes");
return;
}
if (node->has_mem) {
numa_info[nodenr].node_mem = node->mem;
warn_report("Parameter -numa node,mem is deprecated,"
" use -numa node,memdev instead");
}
if (node->has_memdev) {
Object *o;
o = object_resolve_path_type(node->memdev, TYPE_MEMORY_BACKEND, NULL);
if (!o) {
error_setg(errp, "memdev=%s is ambiguous", node->memdev);
return;
}
object_ref(o);
numa_info[nodenr].node_mem = object_property_get_uint(o, "size", NULL);
numa_info[nodenr].node_memdev = MEMORY_BACKEND(o);
}
numa_info[nodenr].present = true;
max_numa_nodeid = MAX(max_numa_nodeid, nodenr + 1);
nb_numa_nodes++;
}
static void parse_numa_distance(NumaDistOptions *dist, Error **errp)
{
uint16_t src = dist->src;
uint16_t dst = dist->dst;
uint8_t val = dist->val;
if (src >= MAX_NODES || dst >= MAX_NODES) {
error_setg(errp, "Parameter '%s' expects an integer between 0 and %d",
src >= MAX_NODES ? "src" : "dst", MAX_NODES - 1);
return;
}
if (!numa_info[src].present || !numa_info[dst].present) {
error_setg(errp, "Source/Destination NUMA node is missing. "
"Please use '-numa node' option to declare it first.");
return;
}
if (val < NUMA_DISTANCE_MIN) {
error_setg(errp, "NUMA distance (%" PRIu8 ") is invalid, "
"it shouldn't be less than %d.",
val, NUMA_DISTANCE_MIN);
return;
}
if (src == dst && val != NUMA_DISTANCE_MIN) {
error_setg(errp, "Local distance of node %d should be %d.",
src, NUMA_DISTANCE_MIN);
return;
}
numa_info[src].distance[dst] = val;
have_numa_distance = true;
}
void set_numa_options(MachineState *ms, NumaOptions *object, Error **errp)
{
Error *err = NULL;
switch (object->type) {
case NUMA_OPTIONS_TYPE_NODE:
parse_numa_node(ms, &object->u.node, &err);
if (err) {
goto end;
}
break;
case NUMA_OPTIONS_TYPE_DIST:
parse_numa_distance(&object->u.dist, &err);
if (err) {
goto end;
}
break;
case NUMA_OPTIONS_TYPE_CPU:
if (!object->u.cpu.has_node_id) {
error_setg(&err, "Missing mandatory node-id property");
goto end;
}
if (!numa_info[object->u.cpu.node_id].present) {
error_setg(&err, "Invalid node-id=%" PRId64 ", NUMA node must be "
"defined with -numa node,nodeid=ID before it's used with "
"-numa cpu,node-id=ID", object->u.cpu.node_id);
goto end;
}
machine_set_cpu_numa_node(ms, qapi_NumaCpuOptions_base(&object->u.cpu),
&err);
break;
default:
abort();
}
end:
error_propagate(errp, err);
}
static int parse_numa(void *opaque, QemuOpts *opts, Error **errp)
{
NumaOptions *object = NULL;
MachineState *ms = MACHINE(opaque);
Error *err = NULL;
Visitor *v = opts_visitor_new(opts);
visit_type_NumaOptions(v, NULL, &object, &err);
visit_free(v);
if (err) {
goto end;
}
/* Fix up legacy suffix-less format */
if ((object->type == NUMA_OPTIONS_TYPE_NODE) && object->u.node.has_mem) {
const char *mem_str = qemu_opt_get(opts, "mem");
qemu_strtosz_MiB(mem_str, NULL, &object->u.node.mem);
}
set_numa_options(ms, object, &err);
end:
qapi_free_NumaOptions(object);
if (err) {
error_propagate(errp, err);
return -1;
}
return 0;
}
/* If all node pair distances are symmetric, then only distances
* in one direction are enough. If there is even one asymmetric
* pair, though, then all distances must be provided. The
* distance from a node to itself is always NUMA_DISTANCE_MIN,
* so providing it is never necessary.
*/
static void validate_numa_distance(void)
{
int src, dst;
bool is_asymmetrical = false;
for (src = 0; src < nb_numa_nodes; src++) {
for (dst = src; dst < nb_numa_nodes; dst++) {
if (numa_info[src].distance[dst] == 0 &&
numa_info[dst].distance[src] == 0) {
if (src != dst) {
error_report("The distance between node %d and %d is "
"missing, at least one distance value "
"between each nodes should be provided.",
src, dst);
exit(EXIT_FAILURE);
}
}
if (numa_info[src].distance[dst] != 0 &&
numa_info[dst].distance[src] != 0 &&
numa_info[src].distance[dst] !=
numa_info[dst].distance[src]) {
is_asymmetrical = true;
}
}
}
if (is_asymmetrical) {
for (src = 0; src < nb_numa_nodes; src++) {
for (dst = 0; dst < nb_numa_nodes; dst++) {
if (src != dst && numa_info[src].distance[dst] == 0) {
error_report("At least one asymmetrical pair of "
"distances is given, please provide distances "
"for both directions of all node pairs.");
exit(EXIT_FAILURE);
}
}
}
}
}
static void complete_init_numa_distance(void)
{
int src, dst;
/* Fixup NUMA distance by symmetric policy because if it is an
* asymmetric distance table, it should be a complete table and
* there would not be any missing distance except local node, which
* is verified by validate_numa_distance above.
*/
for (src = 0; src < nb_numa_nodes; src++) {
for (dst = 0; dst < nb_numa_nodes; dst++) {
if (numa_info[src].distance[dst] == 0) {
if (src == dst) {
numa_info[src].distance[dst] = NUMA_DISTANCE_MIN;
} else {
numa_info[src].distance[dst] = numa_info[dst].distance[src];
}
}
}
}
}
void numa_legacy_auto_assign_ram(MachineClass *mc, NodeInfo *nodes,
int nb_nodes, ram_addr_t size)
{
int i;
uint64_t usedmem = 0;
/* Align each node according to the alignment
* requirements of the machine class
*/
for (i = 0; i < nb_nodes - 1; i++) {
nodes[i].node_mem = (size / nb_nodes) &
~((1 << mc->numa_mem_align_shift) - 1);
usedmem += nodes[i].node_mem;
}
nodes[i].node_mem = size - usedmem;
}
void numa_default_auto_assign_ram(MachineClass *mc, NodeInfo *nodes,
int nb_nodes, ram_addr_t size)
{
int i;
uint64_t usedmem = 0, node_mem;
uint64_t granularity = size / nb_nodes;
uint64_t propagate = 0;
for (i = 0; i < nb_nodes - 1; i++) {
node_mem = (granularity + propagate) &
~((1 << mc->numa_mem_align_shift) - 1);
propagate = granularity + propagate - node_mem;
nodes[i].node_mem = node_mem;
usedmem += node_mem;
}
nodes[i].node_mem = size - usedmem;
}
void numa_complete_configuration(MachineState *ms)
{
int i;
MachineClass *mc = MACHINE_GET_CLASS(ms);
/*
* If memory hotplug is enabled (slots > 0) but without '-numa'
* options explicitly on CLI, guestes will break.
*
* Windows: won't enable memory hotplug without SRAT table at all
*
* Linux: if QEMU is started with initial memory all below 4Gb
* and no SRAT table present, guest kernel will use nommu DMA ops,
* which breaks 32bit hw drivers when memory is hotplugged and
* guest tries to use it with that drivers.
*
* Enable NUMA implicitly by adding a new NUMA node automatically.
*/
if (ms->ram_slots > 0 && nb_numa_nodes == 0 &&
mc->auto_enable_numa_with_memhp) {
NumaNodeOptions node = { };
parse_numa_node(ms, &node, &error_abort);
}
assert(max_numa_nodeid <= MAX_NODES);
/* No support for sparse NUMA node IDs yet: */
for (i = max_numa_nodeid - 1; i >= 0; i--) {
/* Report large node IDs first, to make mistakes easier to spot */
if (!numa_info[i].present) {
error_report("numa: Node ID missing: %d", i);
exit(1);
}
}
/* This must be always true if all nodes are present: */
assert(nb_numa_nodes == max_numa_nodeid);
if (nb_numa_nodes > 0) {
uint64_t numa_total;
if (nb_numa_nodes > MAX_NODES) {
nb_numa_nodes = MAX_NODES;
}
/* If no memory size is given for any node, assume the default case
* and distribute the available memory equally across all nodes
*/
for (i = 0; i < nb_numa_nodes; i++) {
if (numa_info[i].node_mem != 0) {
break;
}
}
if (i == nb_numa_nodes) {
assert(mc->numa_auto_assign_ram);
mc->numa_auto_assign_ram(mc, numa_info, nb_numa_nodes, ram_size);
}
numa_total = 0;
for (i = 0; i < nb_numa_nodes; i++) {
numa_total += numa_info[i].node_mem;
}
if (numa_total != ram_size) {
error_report("total memory for NUMA nodes (0x%" PRIx64 ")"
" should equal RAM size (0x" RAM_ADDR_FMT ")",
numa_total, ram_size);
exit(1);
}
/* QEMU needs at least all unique node pair distances to build
* the whole NUMA distance table. QEMU treats the distance table
* as symmetric by default, i.e. distance A->B == distance B->A.
* Thus, QEMU is able to complete the distance table
* initialization even though only distance A->B is provided and
* distance B->A is not. QEMU knows the distance of a node to
* itself is always 10, so A->A distances may be omitted. When
* the distances of two nodes of a pair differ, i.e. distance
* A->B != distance B->A, then that means the distance table is
* asymmetric. In this case, the distances for both directions
* of all node pairs are required.
*/
if (have_numa_distance) {
/* Validate enough NUMA distance information was provided. */
validate_numa_distance();
/* Validation succeeded, now fill in any missing distances. */
complete_init_numa_distance();
}
}
}
void parse_numa_opts(MachineState *ms)
{
qemu_opts_foreach(qemu_find_opts("numa"), parse_numa, ms, &error_fatal);
}
void numa_cpu_pre_plug(const CPUArchId *slot, DeviceState *dev, Error **errp)
{
int node_id = object_property_get_int(OBJECT(dev), "node-id", &error_abort);
if (node_id == CPU_UNSET_NUMA_NODE_ID) {
/* due to bug in libvirt, it doesn't pass node-id from props on
* device_add as expected, so we have to fix it up here */
if (slot->props.has_node_id) {
object_property_set_int(OBJECT(dev), slot->props.node_id,
"node-id", errp);
}
} else if (node_id != slot->props.node_id) {
error_setg(errp, "invalid node-id, must be %"PRId64,
slot->props.node_id);
}
}
static void allocate_system_memory_nonnuma(MemoryRegion *mr, Object *owner,
const char *name,
uint64_t ram_size)
{
if (mem_path) {
#ifdef __linux__
Error *err = NULL;
memory_region_init_ram_from_file(mr, owner, name, ram_size, 0, 0,
mem_path, &err);
if (err) {
error_report_err(err);
if (mem_prealloc) {
exit(1);
}
error_report("falling back to regular RAM allocation.");
/* Legacy behavior: if allocation failed, fall back to
* regular RAM allocation.
*/
mem_path = NULL;
memory_region_init_ram_nomigrate(mr, owner, name, ram_size, &error_fatal);
}
#else
fprintf(stderr, "-mem-path not supported on this host\n");
exit(1);
#endif
} else {
memory_region_init_ram_nomigrate(mr, owner, name, ram_size, &error_fatal);
}
vmstate_register_ram_global(mr);
}
void memory_region_allocate_system_memory(MemoryRegion *mr, Object *owner,
const char *name,
uint64_t ram_size)
{
uint64_t addr = 0;
int i;
if (nb_numa_nodes == 0 || !have_memdevs) {
allocate_system_memory_nonnuma(mr, owner, name, ram_size);
return;
}
memory_region_init(mr, owner, name, ram_size);
for (i = 0; i < nb_numa_nodes; i++) {
uint64_t size = numa_info[i].node_mem;
HostMemoryBackend *backend = numa_info[i].node_memdev;
if (!backend) {
continue;
}
MemoryRegion *seg = host_memory_backend_get_memory(backend);
if (memory_region_is_mapped(seg)) {
char *path = object_get_canonical_path_component(OBJECT(backend));
error_report("memory backend %s is used multiple times. Each "
"-numa option must use a different memdev value.",
path);
g_free(path);
exit(1);
}
host_memory_backend_set_mapped(backend, true);
memory_region_add_subregion(mr, addr, seg);
vmstate_register_ram_global(seg);
addr += size;
}
}
static void numa_stat_memory_devices(NumaNodeMem node_mem[])
{
MemoryDeviceInfoList *info_list = qmp_memory_device_list();
MemoryDeviceInfoList *info;
PCDIMMDeviceInfo *pcdimm_info;
VirtioPMEMDeviceInfo *vpi;
for (info = info_list; info; info = info->next) {
MemoryDeviceInfo *value = info->value;
if (value) {
switch (value->type) {
case MEMORY_DEVICE_INFO_KIND_DIMM:
case MEMORY_DEVICE_INFO_KIND_NVDIMM:
pcdimm_info = value->type == MEMORY_DEVICE_INFO_KIND_DIMM ?
value->u.dimm.data : value->u.nvdimm.data;
node_mem[pcdimm_info->node].node_mem += pcdimm_info->size;
node_mem[pcdimm_info->node].node_plugged_mem +=
pcdimm_info->size;
break;
case MEMORY_DEVICE_INFO_KIND_VIRTIO_PMEM:
vpi = value->u.virtio_pmem.data;
/* TODO: once we support numa, assign to right node */
node_mem[0].node_mem += vpi->size;
node_mem[0].node_plugged_mem += vpi->size;
break;
default:
g_assert_not_reached();
}
}
}
qapi_free_MemoryDeviceInfoList(info_list);
}
void query_numa_node_mem(NumaNodeMem node_mem[])
{
int i;
if (nb_numa_nodes <= 0) {
return;
}
numa_stat_memory_devices(node_mem);
for (i = 0; i < nb_numa_nodes; i++) {
node_mem[i].node_mem += numa_info[i].node_mem;
}
}
void ram_block_notifier_add(RAMBlockNotifier *n)
{
QLIST_INSERT_HEAD(&ram_list.ramblock_notifiers, n, next);
}
void ram_block_notifier_remove(RAMBlockNotifier *n)
{
QLIST_REMOVE(n, next);
}
void ram_block_notify_add(void *host, size_t size)
{
RAMBlockNotifier *notifier;
QLIST_FOREACH(notifier, &ram_list.ramblock_notifiers, next) {
notifier->ram_block_added(notifier, host, size);
}
}
void ram_block_notify_remove(void *host, size_t size)
{
RAMBlockNotifier *notifier;
QLIST_FOREACH(notifier, &ram_list.ramblock_notifiers, next) {
notifier->ram_block_removed(notifier, host, size);
}
}