linux/drivers/acpi/numa/hmat.c

864 lines
21 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2019, Intel Corporation.
*
* Heterogeneous Memory Attributes Table (HMAT) representation
*
* This program parses and reports the platform's HMAT tables, and registers
* the applicable attributes with the node's interfaces.
*/
#define pr_fmt(fmt) "acpi/hmat: " fmt
#define dev_fmt(fmt) "acpi/hmat: " fmt
#include <linux/acpi.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/platform_device.h>
#include <linux/list_sort.h>
#include <linux/memregion.h>
#include <linux/memory.h>
#include <linux/mutex.h>
#include <linux/node.h>
#include <linux/sysfs.h>
static u8 hmat_revision;
static LIST_HEAD(targets);
static LIST_HEAD(initiators);
static LIST_HEAD(localities);
static DEFINE_MUTEX(target_lock);
/*
* The defined enum order is used to prioritize attributes to break ties when
* selecting the best performing node.
*/
enum locality_types {
WRITE_LATENCY,
READ_LATENCY,
WRITE_BANDWIDTH,
READ_BANDWIDTH,
};
static struct memory_locality *localities_types[4];
struct target_cache {
struct list_head node;
struct node_cache_attrs cache_attrs;
};
struct memory_target {
struct list_head node;
unsigned int memory_pxm;
unsigned int processor_pxm;
struct resource memregions;
struct node_hmem_attrs hmem_attrs;
struct list_head caches;
struct node_cache_attrs cache_attrs;
bool registered;
};
struct memory_initiator {
struct list_head node;
unsigned int processor_pxm;
};
struct memory_locality {
struct list_head node;
struct acpi_hmat_locality *hmat_loc;
};
static struct memory_initiator *find_mem_initiator(unsigned int cpu_pxm)
{
struct memory_initiator *initiator;
list_for_each_entry(initiator, &initiators, node)
if (initiator->processor_pxm == cpu_pxm)
return initiator;
return NULL;
}
static struct memory_target *find_mem_target(unsigned int mem_pxm)
{
struct memory_target *target;
list_for_each_entry(target, &targets, node)
if (target->memory_pxm == mem_pxm)
return target;
return NULL;
}
static __init void alloc_memory_initiator(unsigned int cpu_pxm)
{
struct memory_initiator *initiator;
if (pxm_to_node(cpu_pxm) == NUMA_NO_NODE)
return;
initiator = find_mem_initiator(cpu_pxm);
if (initiator)
return;
initiator = kzalloc(sizeof(*initiator), GFP_KERNEL);
if (!initiator)
return;
initiator->processor_pxm = cpu_pxm;
list_add_tail(&initiator->node, &initiators);
}
static __init void alloc_memory_target(unsigned int mem_pxm,
resource_size_t start, resource_size_t len)
{
struct memory_target *target;
target = find_mem_target(mem_pxm);
if (!target) {
target = kzalloc(sizeof(*target), GFP_KERNEL);
if (!target)
return;
target->memory_pxm = mem_pxm;
target->processor_pxm = PXM_INVAL;
target->memregions = (struct resource) {
.name = "ACPI mem",
.start = 0,
.end = -1,
.flags = IORESOURCE_MEM,
};
list_add_tail(&target->node, &targets);
INIT_LIST_HEAD(&target->caches);
}
/*
* There are potentially multiple ranges per PXM, so record each
* in the per-target memregions resource tree.
*/
if (!__request_region(&target->memregions, start, len, "memory target",
IORESOURCE_MEM))
pr_warn("failed to reserve %#llx - %#llx in pxm: %d\n",
start, start + len, mem_pxm);
}
static __init const char *hmat_data_type(u8 type)
{
switch (type) {
case ACPI_HMAT_ACCESS_LATENCY:
return "Access Latency";
case ACPI_HMAT_READ_LATENCY:
return "Read Latency";
case ACPI_HMAT_WRITE_LATENCY:
return "Write Latency";
case ACPI_HMAT_ACCESS_BANDWIDTH:
return "Access Bandwidth";
case ACPI_HMAT_READ_BANDWIDTH:
return "Read Bandwidth";
case ACPI_HMAT_WRITE_BANDWIDTH:
return "Write Bandwidth";
default:
return "Reserved";
}
}
static __init const char *hmat_data_type_suffix(u8 type)
{
switch (type) {
case ACPI_HMAT_ACCESS_LATENCY:
case ACPI_HMAT_READ_LATENCY:
case ACPI_HMAT_WRITE_LATENCY:
return " nsec";
case ACPI_HMAT_ACCESS_BANDWIDTH:
case ACPI_HMAT_READ_BANDWIDTH:
case ACPI_HMAT_WRITE_BANDWIDTH:
return " MB/s";
default:
return "";
}
}
static u32 hmat_normalize(u16 entry, u64 base, u8 type)
{
u32 value;
/*
* Check for invalid and overflow values
*/
if (entry == 0xffff || !entry)
return 0;
else if (base > (UINT_MAX / (entry)))
return 0;
/*
* Divide by the base unit for version 1, convert latency from
* picosenonds to nanoseconds if revision 2.
*/
value = entry * base;
if (hmat_revision == 1) {
if (value < 10)
return 0;
value = DIV_ROUND_UP(value, 10);
} else if (hmat_revision == 2) {
switch (type) {
case ACPI_HMAT_ACCESS_LATENCY:
case ACPI_HMAT_READ_LATENCY:
case ACPI_HMAT_WRITE_LATENCY:
value = DIV_ROUND_UP(value, 1000);
break;
default:
break;
}
}
return value;
}
static void hmat_update_target_access(struct memory_target *target,
u8 type, u32 value)
{
switch (type) {
case ACPI_HMAT_ACCESS_LATENCY:
target->hmem_attrs.read_latency = value;
target->hmem_attrs.write_latency = value;
break;
case ACPI_HMAT_READ_LATENCY:
target->hmem_attrs.read_latency = value;
break;
case ACPI_HMAT_WRITE_LATENCY:
target->hmem_attrs.write_latency = value;
break;
case ACPI_HMAT_ACCESS_BANDWIDTH:
target->hmem_attrs.read_bandwidth = value;
target->hmem_attrs.write_bandwidth = value;
break;
case ACPI_HMAT_READ_BANDWIDTH:
target->hmem_attrs.read_bandwidth = value;
break;
case ACPI_HMAT_WRITE_BANDWIDTH:
target->hmem_attrs.write_bandwidth = value;
break;
default:
break;
}
}
static __init void hmat_add_locality(struct acpi_hmat_locality *hmat_loc)
{
struct memory_locality *loc;
loc = kzalloc(sizeof(*loc), GFP_KERNEL);
if (!loc) {
pr_notice_once("Failed to allocate HMAT locality\n");
return;
}
loc->hmat_loc = hmat_loc;
list_add_tail(&loc->node, &localities);
switch (hmat_loc->data_type) {
case ACPI_HMAT_ACCESS_LATENCY:
localities_types[READ_LATENCY] = loc;
localities_types[WRITE_LATENCY] = loc;
break;
case ACPI_HMAT_READ_LATENCY:
localities_types[READ_LATENCY] = loc;
break;
case ACPI_HMAT_WRITE_LATENCY:
localities_types[WRITE_LATENCY] = loc;
break;
case ACPI_HMAT_ACCESS_BANDWIDTH:
localities_types[READ_BANDWIDTH] = loc;
localities_types[WRITE_BANDWIDTH] = loc;
break;
case ACPI_HMAT_READ_BANDWIDTH:
localities_types[READ_BANDWIDTH] = loc;
break;
case ACPI_HMAT_WRITE_BANDWIDTH:
localities_types[WRITE_BANDWIDTH] = loc;
break;
default:
break;
}
}
static __init int hmat_parse_locality(union acpi_subtable_headers *header,
const unsigned long end)
{
struct acpi_hmat_locality *hmat_loc = (void *)header;
struct memory_target *target;
unsigned int init, targ, total_size, ipds, tpds;
u32 *inits, *targs, value;
u16 *entries;
u8 type, mem_hier;
if (hmat_loc->header.length < sizeof(*hmat_loc)) {
pr_notice("HMAT: Unexpected locality header length: %u\n",
hmat_loc->header.length);
return -EINVAL;
}
type = hmat_loc->data_type;
mem_hier = hmat_loc->flags & ACPI_HMAT_MEMORY_HIERARCHY;
ipds = hmat_loc->number_of_initiator_Pds;
tpds = hmat_loc->number_of_target_Pds;
total_size = sizeof(*hmat_loc) + sizeof(*entries) * ipds * tpds +
sizeof(*inits) * ipds + sizeof(*targs) * tpds;
if (hmat_loc->header.length < total_size) {
pr_notice("HMAT: Unexpected locality header length:%u, minimum required:%u\n",
hmat_loc->header.length, total_size);
return -EINVAL;
}
pr_info("HMAT: Locality: Flags:%02x Type:%s Initiator Domains:%u Target Domains:%u Base:%lld\n",
hmat_loc->flags, hmat_data_type(type), ipds, tpds,
hmat_loc->entry_base_unit);
inits = (u32 *)(hmat_loc + 1);
targs = inits + ipds;
entries = (u16 *)(targs + tpds);
for (init = 0; init < ipds; init++) {
alloc_memory_initiator(inits[init]);
for (targ = 0; targ < tpds; targ++) {
value = hmat_normalize(entries[init * tpds + targ],
hmat_loc->entry_base_unit,
type);
pr_info(" Initiator-Target[%u-%u]:%u%s\n",
inits[init], targs[targ], value,
hmat_data_type_suffix(type));
if (mem_hier == ACPI_HMAT_MEMORY) {
target = find_mem_target(targs[targ]);
if (target && target->processor_pxm == inits[init])
hmat_update_target_access(target, type, value);
}
}
}
if (mem_hier == ACPI_HMAT_MEMORY)
hmat_add_locality(hmat_loc);
return 0;
}
static __init int hmat_parse_cache(union acpi_subtable_headers *header,
const unsigned long end)
{
struct acpi_hmat_cache *cache = (void *)header;
struct memory_target *target;
struct target_cache *tcache;
u32 attrs;
if (cache->header.length < sizeof(*cache)) {
pr_notice("HMAT: Unexpected cache header length: %u\n",
cache->header.length);
return -EINVAL;
}
attrs = cache->cache_attributes;
pr_info("HMAT: Cache: Domain:%u Size:%llu Attrs:%08x SMBIOS Handles:%d\n",
cache->memory_PD, cache->cache_size, attrs,
cache->number_of_SMBIOShandles);
target = find_mem_target(cache->memory_PD);
if (!target)
return 0;
tcache = kzalloc(sizeof(*tcache), GFP_KERNEL);
if (!tcache) {
pr_notice_once("Failed to allocate HMAT cache info\n");
return 0;
}
tcache->cache_attrs.size = cache->cache_size;
tcache->cache_attrs.level = (attrs & ACPI_HMAT_CACHE_LEVEL) >> 4;
tcache->cache_attrs.line_size = (attrs & ACPI_HMAT_CACHE_LINE_SIZE) >> 16;
switch ((attrs & ACPI_HMAT_CACHE_ASSOCIATIVITY) >> 8) {
case ACPI_HMAT_CA_DIRECT_MAPPED:
tcache->cache_attrs.indexing = NODE_CACHE_DIRECT_MAP;
break;
case ACPI_HMAT_CA_COMPLEX_CACHE_INDEXING:
tcache->cache_attrs.indexing = NODE_CACHE_INDEXED;
break;
case ACPI_HMAT_CA_NONE:
default:
tcache->cache_attrs.indexing = NODE_CACHE_OTHER;
break;
}
switch ((attrs & ACPI_HMAT_WRITE_POLICY) >> 12) {
case ACPI_HMAT_CP_WB:
tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_BACK;
break;
case ACPI_HMAT_CP_WT:
tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_THROUGH;
break;
case ACPI_HMAT_CP_NONE:
default:
tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_OTHER;
break;
}
list_add_tail(&tcache->node, &target->caches);
return 0;
}
static int __init hmat_parse_proximity_domain(union acpi_subtable_headers *header,
const unsigned long end)
{
struct acpi_hmat_proximity_domain *p = (void *)header;
struct memory_target *target = NULL;
if (p->header.length != sizeof(*p)) {
pr_notice("HMAT: Unexpected address range header length: %u\n",
p->header.length);
return -EINVAL;
}
if (hmat_revision == 1)
pr_info("HMAT: Memory (%#llx length %#llx) Flags:%04x Processor Domain:%u Memory Domain:%u\n",
p->reserved3, p->reserved4, p->flags, p->processor_PD,
p->memory_PD);
else
pr_info("HMAT: Memory Flags:%04x Processor Domain:%u Memory Domain:%u\n",
p->flags, p->processor_PD, p->memory_PD);
if (p->flags & ACPI_HMAT_MEMORY_PD_VALID && hmat_revision == 1) {
target = find_mem_target(p->memory_PD);
if (!target) {
pr_debug("HMAT: Memory Domain missing from SRAT\n");
return -EINVAL;
}
}
if (target && p->flags & ACPI_HMAT_PROCESSOR_PD_VALID) {
int p_node = pxm_to_node(p->processor_PD);
if (p_node == NUMA_NO_NODE) {
pr_debug("HMAT: Invalid Processor Domain\n");
return -EINVAL;
}
target->processor_pxm = p->processor_PD;
}
return 0;
}
static int __init hmat_parse_subtable(union acpi_subtable_headers *header,
const unsigned long end)
{
struct acpi_hmat_structure *hdr = (void *)header;
if (!hdr)
return -EINVAL;
switch (hdr->type) {
case ACPI_HMAT_TYPE_PROXIMITY:
return hmat_parse_proximity_domain(header, end);
case ACPI_HMAT_TYPE_LOCALITY:
return hmat_parse_locality(header, end);
case ACPI_HMAT_TYPE_CACHE:
return hmat_parse_cache(header, end);
default:
return -EINVAL;
}
}
static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
const unsigned long end)
{
struct acpi_srat_mem_affinity *ma = (void *)header;
if (!ma)
return -EINVAL;
if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
return 0;
alloc_memory_target(ma->proximity_domain, ma->base_address, ma->length);
return 0;
}
static u32 hmat_initiator_perf(struct memory_target *target,
struct memory_initiator *initiator,
struct acpi_hmat_locality *hmat_loc)
{
unsigned int ipds, tpds, i, idx = 0, tdx = 0;
u32 *inits, *targs;
u16 *entries;
ipds = hmat_loc->number_of_initiator_Pds;
tpds = hmat_loc->number_of_target_Pds;
inits = (u32 *)(hmat_loc + 1);
targs = inits + ipds;
entries = (u16 *)(targs + tpds);
for (i = 0; i < ipds; i++) {
if (inits[i] == initiator->processor_pxm) {
idx = i;
break;
}
}
if (i == ipds)
return 0;
for (i = 0; i < tpds; i++) {
if (targs[i] == target->memory_pxm) {
tdx = i;
break;
}
}
if (i == tpds)
return 0;
return hmat_normalize(entries[idx * tpds + tdx],
hmat_loc->entry_base_unit,
hmat_loc->data_type);
}
static bool hmat_update_best(u8 type, u32 value, u32 *best)
{
bool updated = false;
if (!value)
return false;
switch (type) {
case ACPI_HMAT_ACCESS_LATENCY:
case ACPI_HMAT_READ_LATENCY:
case ACPI_HMAT_WRITE_LATENCY:
if (!*best || *best > value) {
*best = value;
updated = true;
}
break;
case ACPI_HMAT_ACCESS_BANDWIDTH:
case ACPI_HMAT_READ_BANDWIDTH:
case ACPI_HMAT_WRITE_BANDWIDTH:
if (!*best || *best < value) {
*best = value;
updated = true;
}
break;
}
return updated;
}
static int initiator_cmp(void *priv, struct list_head *a, struct list_head *b)
{
struct memory_initiator *ia;
struct memory_initiator *ib;
unsigned long *p_nodes = priv;
ia = list_entry(a, struct memory_initiator, node);
ib = list_entry(b, struct memory_initiator, node);
set_bit(ia->processor_pxm, p_nodes);
set_bit(ib->processor_pxm, p_nodes);
return ia->processor_pxm - ib->processor_pxm;
}
static void hmat_register_target_initiators(struct memory_target *target)
{
static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
struct memory_initiator *initiator;
unsigned int mem_nid, cpu_nid;
struct memory_locality *loc = NULL;
u32 best = 0;
int i;
mem_nid = pxm_to_node(target->memory_pxm);
/*
* If the Address Range Structure provides a local processor pxm, link
* only that one. Otherwise, find the best performance attributes and
* register all initiators that match.
*/
if (target->processor_pxm != PXM_INVAL) {
cpu_nid = pxm_to_node(target->processor_pxm);
register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
return;
}
if (list_empty(&localities))
return;
/*
* We need the initiator list sorted so we can use bitmap_clear for
* previously set initiators when we find a better memory accessor.
* We'll also use the sorting to prime the candidate nodes with known
* initiators.
*/
bitmap_zero(p_nodes, MAX_NUMNODES);
list_sort(p_nodes, &initiators, initiator_cmp);
for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
loc = localities_types[i];
if (!loc)
continue;
best = 0;
list_for_each_entry(initiator, &initiators, node) {
u32 value;
if (!test_bit(initiator->processor_pxm, p_nodes))
continue;
value = hmat_initiator_perf(target, initiator, loc->hmat_loc);
if (hmat_update_best(loc->hmat_loc->data_type, value, &best))
bitmap_clear(p_nodes, 0, initiator->processor_pxm);
if (value != best)
clear_bit(initiator->processor_pxm, p_nodes);
}
if (best)
hmat_update_target_access(target, loc->hmat_loc->data_type, best);
}
for_each_set_bit(i, p_nodes, MAX_NUMNODES) {
cpu_nid = pxm_to_node(i);
register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
}
}
static void hmat_register_target_cache(struct memory_target *target)
{
unsigned mem_nid = pxm_to_node(target->memory_pxm);
struct target_cache *tcache;
list_for_each_entry(tcache, &target->caches, node)
node_add_cache(mem_nid, &tcache->cache_attrs);
}
static void hmat_register_target_perf(struct memory_target *target)
{
unsigned mem_nid = pxm_to_node(target->memory_pxm);
node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0);
}
static void hmat_register_target_device(struct memory_target *target,
struct resource *r)
{
/* define a clean / non-busy resource for the platform device */
struct resource res = {
.start = r->start,
.end = r->end,
.flags = IORESOURCE_MEM,
};
struct platform_device *pdev;
struct memregion_info info;
int rc, id;
rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM,
IORES_DESC_SOFT_RESERVED);
if (rc != REGION_INTERSECTS)
return;
id = memregion_alloc(GFP_KERNEL);
if (id < 0) {
pr_err("memregion allocation failure for %pr\n", &res);
return;
}
pdev = platform_device_alloc("hmem", id);
if (!pdev) {
pr_err("hmem device allocation failure for %pr\n", &res);
goto out_pdev;
}
pdev->dev.numa_node = acpi_map_pxm_to_online_node(target->memory_pxm);
info = (struct memregion_info) {
.target_node = acpi_map_pxm_to_node(target->memory_pxm),
};
rc = platform_device_add_data(pdev, &info, sizeof(info));
if (rc < 0) {
pr_err("hmem memregion_info allocation failure for %pr\n", &res);
goto out_pdev;
}
rc = platform_device_add_resources(pdev, &res, 1);
if (rc < 0) {
pr_err("hmem resource allocation failure for %pr\n", &res);
goto out_resource;
}
rc = platform_device_add(pdev);
if (rc < 0) {
dev_err(&pdev->dev, "device add failed for %pr\n", &res);
goto out_resource;
}
return;
out_resource:
put_device(&pdev->dev);
out_pdev:
memregion_free(id);
}
static void hmat_register_target_devices(struct memory_target *target)
{
struct resource *res;
/*
* Do not bother creating devices if no driver is available to
* consume them.
*/
if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM))
return;
for (res = target->memregions.child; res; res = res->sibling)
hmat_register_target_device(target, res);
}
static void hmat_register_target(struct memory_target *target)
{
int nid = pxm_to_node(target->memory_pxm);
/*
* Devices may belong to either an offline or online
* node, so unconditionally add them.
*/
hmat_register_target_devices(target);
/*
* Skip offline nodes. This can happen when memory
* marked EFI_MEMORY_SP, "specific purpose", is applied
* to all the memory in a promixity domain leading to
* the node being marked offline / unplugged, or if
* memory-only "hotplug" node is offline.
*/
if (nid == NUMA_NO_NODE || !node_online(nid))
return;
mutex_lock(&target_lock);
if (!target->registered) {
hmat_register_target_initiators(target);
hmat_register_target_cache(target);
hmat_register_target_perf(target);
target->registered = true;
}
mutex_unlock(&target_lock);
}
static void hmat_register_targets(void)
{
struct memory_target *target;
list_for_each_entry(target, &targets, node)
hmat_register_target(target);
}
static int hmat_callback(struct notifier_block *self,
unsigned long action, void *arg)
{
struct memory_target *target;
struct memory_notify *mnb = arg;
int pxm, nid = mnb->status_change_nid;
if (nid == NUMA_NO_NODE || action != MEM_ONLINE)
return NOTIFY_OK;
pxm = node_to_pxm(nid);
target = find_mem_target(pxm);
if (!target)
return NOTIFY_OK;
hmat_register_target(target);
return NOTIFY_OK;
}
static struct notifier_block hmat_callback_nb = {
.notifier_call = hmat_callback,
.priority = 2,
};
static __init void hmat_free_structures(void)
{
struct memory_target *target, *tnext;
struct memory_locality *loc, *lnext;
struct memory_initiator *initiator, *inext;
struct target_cache *tcache, *cnext;
list_for_each_entry_safe(target, tnext, &targets, node) {
struct resource *res, *res_next;
list_for_each_entry_safe(tcache, cnext, &target->caches, node) {
list_del(&tcache->node);
kfree(tcache);
}
list_del(&target->node);
res = target->memregions.child;
while (res) {
res_next = res->sibling;
__release_region(&target->memregions, res->start,
resource_size(res));
res = res_next;
}
kfree(target);
}
list_for_each_entry_safe(initiator, inext, &initiators, node) {
list_del(&initiator->node);
kfree(initiator);
}
list_for_each_entry_safe(loc, lnext, &localities, node) {
list_del(&loc->node);
kfree(loc);
}
}
static __init int hmat_init(void)
{
struct acpi_table_header *tbl;
enum acpi_hmat_type i;
acpi_status status;
if (srat_disabled())
return 0;
status = acpi_get_table(ACPI_SIG_SRAT, 0, &tbl);
if (ACPI_FAILURE(status))
return 0;
if (acpi_table_parse_entries(ACPI_SIG_SRAT,
sizeof(struct acpi_table_srat),
ACPI_SRAT_TYPE_MEMORY_AFFINITY,
srat_parse_mem_affinity, 0) < 0)
goto out_put;
acpi_put_table(tbl);
status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
if (ACPI_FAILURE(status))
goto out_put;
hmat_revision = tbl->revision;
switch (hmat_revision) {
case 1:
case 2:
break;
default:
pr_notice("Ignoring HMAT: Unknown revision:%d\n", hmat_revision);
goto out_put;
}
for (i = ACPI_HMAT_TYPE_PROXIMITY; i < ACPI_HMAT_TYPE_RESERVED; i++) {
if (acpi_table_parse_entries(ACPI_SIG_HMAT,
sizeof(struct acpi_table_hmat), i,
hmat_parse_subtable, 0) < 0) {
pr_notice("Ignoring HMAT: Invalid table");
goto out_put;
}
}
hmat_register_targets();
/* Keep the table and structures if the notifier may use them */
if (!register_hotmemory_notifier(&hmat_callback_nb))
return 0;
out_put:
hmat_free_structures();
acpi_put_table(tbl);
return 0;
}
device_initcall(hmat_init);