Commit 888a589f authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
Browse files

mm, x86: remove MEMORY_HOTPLUG_RESERVE related code 



after:

 | commit b263295d
 | Author: Christoph Lameter <clameter@sgi.com>
 | Date:   Wed Jan 30 13:30:47 2008 +0100
 |
 |    x86: 64-bit, make sparsemem vmemmap the only memory model

we don't have MEMORY_HOTPLUG_RESERVE anymore.

Historically, x86-64 had an architecture-specific method for memory hotplug
whereby it scanned the SRAT for physical memory ranges that could be
potentially used for memory hot-add later. By reserving those ranges
without physical memory, the memmap would be allocated and left dormant
until needed. This depended on the DISCONTIG memory model which has been
removed so the code implementing HOTPLUG_RESERVE is now dead.

This patch removes the dead code used by MEMORY_HOTPLUG_RESERVE.

(Changelog authored by Mel.)

v2: updated changelog, and remove hotadd= in doc

[ Impact: remove dead code ]

Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Reviewed-by: default avatarChristoph Lameter <cl@linux-foundation.org>
Reviewed-by: default avatarMel Gorman <mel@csn.ul.ie>
Workflow-found-OK-by: default avatarAndrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A0C4910.7090508@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b286e218

Documentation/x86/x86_64/boot-options.txt

+0 −5
Original line number Diff line number Diff line
@@ -150,11 +150,6 @@ NUMA 
		Otherwise, the remaining system RAM is allocated to an

		additional node.



  numa=hotadd=percent

		Only allow hotadd memory to preallocate page structures upto

		percent of already available memory.

		numa=hotadd=0 will disable hotadd memory.



ACPI



  acpi=off	Don't enable ACPI

arch/x86/include/asm/numa_64.h

+0 −3
Original line number Diff line number Diff line
@@ -17,9 +17,6 @@ extern int compute_hash_shift(struct bootnode *nodes, int numblks, 
extern void numa_init_array(void);

extern int numa_off;



extern void srat_reserve_add_area(int nodeid);

extern int hotadd_percent;



extern s16 apicid_to_node[MAX_LOCAL_APIC];



extern unsigned long numa_free_all_bootmem(void);

arch/x86/mm/numa_64.c

+0 −5
Original line number Diff line number Diff line
@@ -272,9 +272,6 @@ void __init setup_node_bootmem(int nodeid, unsigned long start, 
		reserve_bootmem_node(NODE_DATA(nodeid), bootmap_start,

				 bootmap_pages<<PAGE_SHIFT, BOOTMEM_DEFAULT);



#ifdef CONFIG_ACPI_NUMA

	srat_reserve_add_area(nodeid);

#endif

	node_set_online(nodeid);

}
@@ -591,8 +588,6 @@ static __init int numa_setup(char *opt) 
#ifdef CONFIG_ACPI_NUMA

	if (!strncmp(opt, "noacpi", 6))

		acpi_numa = -1;

	if (!strncmp(opt, "hotadd=", 7))

		hotadd_percent = simple_strtoul(opt+7, NULL, 10);

#endif

	return 0;

}

arch/x86/mm/srat_64.c

+12 −51
Original line number Diff line number Diff line
@@ -31,8 +31,6 @@ static nodemask_t nodes_parsed __initdata; 
static nodemask_t cpu_nodes_parsed __initdata;

static struct bootnode nodes[MAX_NUMNODES] __initdata;

static struct bootnode nodes_add[MAX_NUMNODES];

static int found_add_area __initdata;

int hotadd_percent __initdata = 0;



static int num_node_memblks __initdata;

static struct bootnode node_memblk_range[NR_NODE_MEMBLKS] __initdata;
@@ -66,9 +64,6 @@ static __init void cutoff_node(int i, unsigned long start, unsigned long end) 
{

	struct bootnode *nd = &nodes[i];



	if (found_add_area)

		return;



	if (nd->start < start) {

		nd->start = start;

		if (nd->end < nd->start)
@@ -86,7 +81,6 @@ static __init void bad_srat(void) 
	int i;

	printk(KERN_ERR "SRAT: SRAT not used.\n");

	acpi_numa = -1;

	found_add_area = 0;

	for (i = 0; i < MAX_LOCAL_APIC; i++)

		apicid_to_node[i] = NUMA_NO_NODE;

	for (i = 0; i < MAX_NUMNODES; i++)
@@ -182,24 +176,21 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa) 
	       pxm, apic_id, node);

}



static int update_end_of_memory(unsigned long end) {return -1;}

static int hotadd_enough_memory(struct bootnode *nd) {return 1;}

#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE

static inline int save_add_info(void) {return 1;}

#else

static inline int save_add_info(void) {return 0;}

#endif

/*

 * Update nodes_add and decide if to include add are in the zone.

 * Both SPARSE and RESERVE need nodes_add information.

 * This code supports one contiguous hot add area per node.

 * Update nodes_add[]

 * This code supports one contiguous hot add area per node

 */

static int __init

reserve_hotadd(int node, unsigned long start, unsigned long end)

static void __init

update_nodes_add(int node, unsigned long start, unsigned long end)

{

	unsigned long s_pfn = start >> PAGE_SHIFT;

	unsigned long e_pfn = end >> PAGE_SHIFT;

	int ret = 0, changed = 0;

	int changed = 0;

	struct bootnode *nd = &nodes_add[node];



	/* I had some trouble with strange memory hotadd regions breaking
@@ -210,7 +201,7 @@ reserve_hotadd(int node, unsigned long start, unsigned long end) 
	   mistakes */

	if ((signed long)(end - start) < NODE_MIN_SIZE) {

		printk(KERN_ERR "SRAT: Hotplug area too small\n");

		return -1;

		return;

	}



	/* This check might be a bit too strict, but I'm keeping it for now. */
@@ -218,12 +209,7 @@ reserve_hotadd(int node, unsigned long start, unsigned long end) 
		printk(KERN_ERR

			"SRAT: Hotplug area %lu -> %lu has existing memory\n",

			s_pfn, e_pfn);

		return -1;

	}



	if (!hotadd_enough_memory(&nodes_add[node]))  {

		printk(KERN_ERR "SRAT: Hotplug area too large\n");

		return -1;

		return;

	}



	/* Looks good */
@@ -245,11 +231,9 @@ reserve_hotadd(int node, unsigned long start, unsigned long end) 
			printk(KERN_ERR "SRAT: Hotplug zone not continuous. Partly ignored\n");

	}



	ret = update_end_of_memory(nd->end);



	if (changed)

	 	printk(KERN_INFO "SRAT: hot plug zone found %Lx - %Lx\n", nd->start, nd->end);

	return ret;

		printk(KERN_INFO "SRAT: hot plug zone found %Lx - %Lx\n",

				 nd->start, nd->end);

}



/* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
@@ -310,13 +294,10 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) 
	       start, end);

	e820_register_active_regions(node, start >> PAGE_SHIFT,

				     end >> PAGE_SHIFT);

	push_node_boundaries(node, nd->start >> PAGE_SHIFT,

						nd->end >> PAGE_SHIFT);



	if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) &&

	    (reserve_hotadd(node, start, end) < 0)) {

		/* Ignore hotadd region. Undo damage */

		printk(KERN_NOTICE "SRAT: Hotplug region ignored\n");

	if (ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) {

		update_nodes_add(node, start, end);

		/* restore nodes[node] */

		*nd = oldnode;

		if ((nd->start | nd->end) == 0)

			node_clear(node, nodes_parsed);
@@ -510,26 +491,6 @@ static int null_slit_node_compare(int a, int b) 
}

#endif /* CONFIG_NUMA_EMU */



void __init srat_reserve_add_area(int nodeid)

{

	if (found_add_area && nodes_add[nodeid].end) {

		u64 total_mb;



		printk(KERN_INFO "SRAT: Reserving hot-add memory space "

				"for node %d at %Lx-%Lx\n",

			nodeid, nodes_add[nodeid].start, nodes_add[nodeid].end);

		total_mb = (nodes_add[nodeid].end - nodes_add[nodeid].start)

					>> PAGE_SHIFT;

		total_mb *= sizeof(struct page);

		total_mb >>= 20;

		printk(KERN_INFO "SRAT: This will cost you %Lu MB of "

				"pre-allocated memory.\n", (unsigned long long)total_mb);

		reserve_bootmem_node(NODE_DATA(nodeid), nodes_add[nodeid].start,

			       nodes_add[nodeid].end - nodes_add[nodeid].start,

			       BOOTMEM_DEFAULT);

	}

}



int __node_distance(int a, int b)

{

	int index;

include/linux/mm.h

+0 −2
Original line number Diff line number Diff line
@@ -1031,8 +1031,6 @@ extern void add_active_range(unsigned int nid, unsigned long start_pfn, 
					unsigned long end_pfn);

extern void remove_active_range(unsigned int nid, unsigned long start_pfn,

					unsigned long end_pfn);

extern void push_node_boundaries(unsigned int nid, unsigned long start_pfn,

					unsigned long end_pfn);

extern void remove_all_active_ranges(void);

extern unsigned long absent_pages_in_range(unsigned long start_pfn,

						unsigned long end_pfn);

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