arch/x86_64/mm/srat.c - maze/linux - Git at Google

 /*
  * 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>
 #include <asm/e820.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 };

 /* Too small nodes confuse the VM badly. Usually they result
    from BIOS bugs. */
 #define NODE_MIN_SIZE (4*1024*1024)

 static int node_to_pxm(int n);

 int pxm_to_node(int pxm)
 {
 	if ((unsigned)pxm >= 256)
 		return -1;
 	/* Extend 0xff to (int)-1 */
 	return (signed char)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())
 		return;
 	if (pa->header.length != sizeof(struct acpi_table_processor_affinity)) {		bad_srat();
 		return;
 	}
 	if (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())
 		return;
 	if (ma->header.length != sizeof(struct acpi_table_memory_affinity)) {
 		bad_srat();
 		return;
 	}
 	if (ma->flags.enabled == 0)
 		return;
 	start = ma->base_addr_lo | ((u64)ma->base_addr_hi << 32);
 	end = start + (ma->length_lo | ((u64)ma->length_hi << 32));
 	pxm = ma->proximity_domain;
 	node = setup_node(pxm);
 	if (node < 0) {
 		printk(KERN_ERR "SRAT: Too many proximity domains.\n");
 		bad_srat();
 		return;
 	}
 	/* 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);
 }

 /* Sanity check to catch more bad SRATs (they are amazingly common).
    Make sure the PXMs cover all memory. */
 static int nodes_cover_memory(void)
 {
 	int i;
 	unsigned long pxmram, e820ram;

 	pxmram = 0;
 	for_each_node_mask(i, nodes_parsed) {
 		unsigned long s = nodes[i].start >> PAGE_SHIFT;
 		unsigned long e = nodes[i].end >> PAGE_SHIFT;
 		pxmram += e - s;
 		pxmram -= e820_hole_size(s, e);
 	}

 	e820ram = end_pfn - e820_hole_size(0, end_pfn);
 	/* We seem to lose 3 pages somewhere. Allow a bit of slack. */
 	if ((long)(e820ram - pxmram) >= 1*1024*1024) {
 		printk(KERN_ERR
 	"SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
 			(pxmram << PAGE_SHIFT) >> 20,
 			(e820ram << PAGE_SHIFT) >> 20);
 		return 0;
 	}
 	return 1;
 }

 static void unparse_node(int node)
 {
 	int i;
 	node_clear(node, nodes_parsed);
 	for (i = 0; i < MAX_LOCAL_APIC; i++) {
 		if (apicid_to_node[i] == node)
 			apicid_to_node[i] = NUMA_NO_NODE;
 	}
 }

 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;

 	/* First clean up the node list */
 	for (i = 0; i < MAX_NUMNODES; i++) {
 		cutoff_node(i, start, end);
 		if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE)
 			unparse_node(i);
 	}

 	if (acpi_numa <= 0)
 		return -1;

 	if (!nodes_cover_memory()) {
 		bad_srat();
 		return -1;
 	}

 	memnode_shift = compute_hash_shift(nodes, MAX_NUMNODES);
 	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);
	/*
	* 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>
	#include <asm/e820.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 };

	/* Too small nodes confuse the VM badly. Usually they result
	from BIOS bugs. */
	#define NODE_MIN_SIZE (410241024)

	static int node_to_pxm(int n);

	int pxm_to_node(int pxm)
	{
	if ((unsigned)pxm >= 256)
	return -1;
	/* Extend 0xff to (int)-1 */
	return (signed char)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())
	return;
	if (pa->header.length != sizeof(struct acpi_table_processor_affinity)) { bad_srat();
	return;
	}
	if (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())
	return;
	if (ma->header.length != sizeof(struct acpi_table_memory_affinity)) {
	bad_srat();
	return;
	}
	if (ma->flags.enabled == 0)
	return;
	start = ma->base_addr_lo \| ((u64)ma->base_addr_hi << 32);
	end = start + (ma->length_lo \| ((u64)ma->length_hi << 32));
	pxm = ma->proximity_domain;
	node = setup_node(pxm);
	if (node < 0) {
	printk(KERN_ERR "SRAT: Too many proximity domains.\n");
	bad_srat();
	return;
	}
	/* 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);
	}

	/* Sanity check to catch more bad SRATs (they are amazingly common).
	Make sure the PXMs cover all memory. */
	static int nodes_cover_memory(void)
	{
	int i;
	unsigned long pxmram, e820ram;

	pxmram = 0;
	for_each_node_mask(i, nodes_parsed) {
	unsigned long s = nodes[i].start >> PAGE_SHIFT;
	unsigned long e = nodes[i].end >> PAGE_SHIFT;
	pxmram += e - s;
	pxmram -= e820_hole_size(s, e);
	}

	e820ram = end_pfn - e820_hole_size(0, end_pfn);
	/* We seem to lose 3 pages somewhere. Allow a bit of slack. */
	if ((long)(e820ram - pxmram) >= 110241024) {
	printk(KERN_ERR
	"SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
	(pxmram << PAGE_SHIFT) >> 20,
	(e820ram << PAGE_SHIFT) >> 20);
	return 0;
	}
	return 1;
	}

	static void unparse_node(int node)
	{
	int i;
	node_clear(node, nodes_parsed);
	for (i = 0; i < MAX_LOCAL_APIC; i++) {
	if (apicid_to_node[i] == node)
	apicid_to_node[i] = NUMA_NO_NODE;
	}
	}

	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;

	/* First clean up the node list */
	for (i = 0; i < MAX_NUMNODES; i++) {
	cutoff_node(i, start, end);
	if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE)
	unparse_node(i);
	}

	if (acpi_numa <= 0)
	return -1;

	if (!nodes_cover_memory()) {
	bad_srat();
	return -1;
	}

	memnode_shift = compute_hash_shift(nodes, MAX_NUMNODES);
	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);