android_kernel_xiaomi_sm8350/arch/x86_64/mm/srat.c
Andi Kleen 1584b89c92 [PATCH] x86_64: Validate SLIT table
A lot of Opteron BIOS just pass 10 in all SLIT entries (10 is the
normalized unit). This is actually worse than the default heuristic
because it leads to pci_distance not knowing the difference between
local and remote nodes anymore. This messes up some NUMA
heuristics in generic code.

In this case it's better to fall back to the default heuristic
which just does nodea == nodeb ? 10 : 20.

This patch does some basic sanity checking on the SLIT and only accepts
the SLIT when it passes.

Invariants enforced are:
- Node to itself shall be 10
- Any other distance shouldn't be 10
- Distances smaller than 10 are illegal

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 19:04:51 -08:00

257 lines
6.1 KiB
C

/*
* ACPI 3.0 based NUMA setup
* Copyright 2004 Andi Kleen, SuSE Labs.
*
* Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
*
* Called from acpi_numa_init while reading the SRAT and SLIT tables.
* Assumes all memory regions belonging to a single proximity domain
* are in one chunk. Holes between them will be included in the node.
*/
#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/mmzone.h>
#include <linux/bitmap.h>
#include <linux/module.h>
#include <linux/topology.h>
#include <asm/proto.h>
#include <asm/numa.h>
static struct acpi_table_slit *acpi_slit;
static nodemask_t nodes_parsed __initdata;
static nodemask_t nodes_found __initdata;
static struct node nodes[MAX_NUMNODES] __initdata;
static __u8 pxm2node[256] = { [0 ... 255] = 0xff };
static int node_to_pxm(int n);
int pxm_to_node(int pxm)
{
if ((unsigned)pxm >= 256)
return 0;
return pxm2node[pxm];
}
static __init int setup_node(int pxm)
{
unsigned node = pxm2node[pxm];
if (node == 0xff) {
if (nodes_weight(nodes_found) >= MAX_NUMNODES)
return -1;
node = first_unset_node(nodes_found);
node_set(node, nodes_found);
pxm2node[pxm] = node;
}
return pxm2node[pxm];
}
static __init int conflicting_nodes(unsigned long start, unsigned long end)
{
int i;
for_each_node_mask(i, nodes_parsed) {
struct node *nd = &nodes[i];
if (nd->start == nd->end)
continue;
if (nd->end > start && nd->start < end)
return i;
if (nd->end == end && nd->start == start)
return i;
}
return -1;
}
static __init void cutoff_node(int i, unsigned long start, unsigned long end)
{
struct node *nd = &nodes[i];
if (nd->start < start) {
nd->start = start;
if (nd->end < nd->start)
nd->start = nd->end;
}
if (nd->end > end) {
nd->end = end;
if (nd->start > nd->end)
nd->start = nd->end;
}
}
static __init void bad_srat(void)
{
int i;
printk(KERN_ERR "SRAT: SRAT not used.\n");
acpi_numa = -1;
for (i = 0; i < MAX_LOCAL_APIC; i++)
apicid_to_node[i] = NUMA_NO_NODE;
}
static __init inline int srat_disabled(void)
{
return numa_off || acpi_numa < 0;
}
/*
* A lot of BIOS fill in 10 (= no distance) everywhere. This messes
* up the NUMA heuristics which wants the local node to have a smaller
* distance than the others.
* Do some quick checks here and only use the SLIT if it passes.
*/
static __init int slit_valid(struct acpi_table_slit *slit)
{
int i, j;
int d = slit->localities;
for (i = 0; i < d; i++) {
for (j = 0; j < d; j++) {
u8 val = slit->entry[d*i + j];
if (i == j) {
if (val != 10)
return 0;
} else if (val <= 10)
return 0;
}
}
return 1;
}
/* Callback for SLIT parsing */
void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
{
if (!slit_valid(slit)) {
printk(KERN_INFO "ACPI: SLIT table looks invalid. Not used.\n");
return;
}
acpi_slit = slit;
}
/* Callback for Proximity Domain -> LAPIC mapping */
void __init
acpi_numa_processor_affinity_init(struct acpi_table_processor_affinity *pa)
{
int pxm, node;
if (srat_disabled() || pa->flags.enabled == 0)
return;
pxm = pa->proximity_domain;
node = setup_node(pxm);
if (node < 0) {
printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm);
bad_srat();
return;
}
apicid_to_node[pa->apic_id] = node;
acpi_numa = 1;
printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
pxm, pa->apic_id, node);
}
/* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
void __init
acpi_numa_memory_affinity_init(struct acpi_table_memory_affinity *ma)
{
struct node *nd;
unsigned long start, end;
int node, pxm;
int i;
if (srat_disabled() || ma->flags.enabled == 0)
return;
pxm = ma->proximity_domain;
node = setup_node(pxm);
if (node < 0) {
printk(KERN_ERR "SRAT: Too many proximity domains.\n");
bad_srat();
return;
}
start = ma->base_addr_lo | ((u64)ma->base_addr_hi << 32);
end = start + (ma->length_lo | ((u64)ma->length_hi << 32));
/* It is fine to add this area to the nodes data it will be used later*/
if (ma->flags.hot_pluggable == 1)
printk(KERN_INFO "SRAT: hot plug zone found %lx - %lx \n",
start, end);
i = conflicting_nodes(start, end);
if (i == node) {
printk(KERN_WARNING
"SRAT: Warning: PXM %d (%lx-%lx) overlaps with itself (%Lx-%Lx)\n",
pxm, start, end, nodes[i].start, nodes[i].end);
} else if (i >= 0) {
printk(KERN_ERR
"SRAT: PXM %d (%lx-%lx) overlaps with PXM %d (%Lx-%Lx)\n",
pxm, start, end, node_to_pxm(i),
nodes[i].start, nodes[i].end);
bad_srat();
return;
}
nd = &nodes[node];
if (!node_test_and_set(node, nodes_parsed)) {
nd->start = start;
nd->end = end;
} else {
if (start < nd->start)
nd->start = start;
if (nd->end < end)
nd->end = end;
}
printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
nd->start, nd->end);
}
void __init acpi_numa_arch_fixup(void) {}
/* Use the information discovered above to actually set up the nodes. */
int __init acpi_scan_nodes(unsigned long start, unsigned long end)
{
int i;
if (acpi_numa <= 0)
return -1;
/* First clean up the node list */
for_each_node_mask(i, nodes_parsed) {
cutoff_node(i, start, end);
if (nodes[i].start == nodes[i].end)
node_clear(i, nodes_parsed);
}
memnode_shift = compute_hash_shift(nodes, nodes_weight(nodes_parsed));
if (memnode_shift < 0) {
printk(KERN_ERR
"SRAT: No NUMA node hash function found. Contact maintainer\n");
bad_srat();
return -1;
}
/* Finally register nodes */
for_each_node_mask(i, nodes_parsed)
setup_node_bootmem(i, nodes[i].start, nodes[i].end);
for (i = 0; i < NR_CPUS; i++) {
if (cpu_to_node[i] == NUMA_NO_NODE)
continue;
if (!node_isset(cpu_to_node[i], nodes_parsed))
numa_set_node(i, NUMA_NO_NODE);
}
numa_init_array();
return 0;
}
static int node_to_pxm(int n)
{
int i;
if (pxm2node[n] == n)
return n;
for (i = 0; i < 256; i++)
if (pxm2node[i] == n)
return i;
return 0;
}
int __node_distance(int a, int b)
{
int index;
if (!acpi_slit)
return a == b ? 10 : 20;
index = acpi_slit->localities * node_to_pxm(a);
return acpi_slit->entry[index + node_to_pxm(b)];
}
EXPORT_SYMBOL(__node_distance);