[PATCH 1/2] sparsemem: put usemap for one node together

Yinghai Lu
2009-12-20T09:20:29Z

could save some buf instead of applying one by one

could help that system that is going to use early_res instead of bootmem
less entries in early_res make search more faster on system with more memory.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
mm/sparse.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++-------------
1 file changed, 66 insertions(+), 18 deletions(-)

Index: linux-2.6/mm/sparse.c
===================================================================
--- linux-2.6.orig/mm/sparse.c
+++ linux-2.6/mm/sparse.c
@@ -271,7 +271,8 @@ static unsigned long *__kmalloc_section_

#ifdef CONFIG_MEMORY_HOTREMOVE
static unsigned long * __init
-sparse_early_usemap_alloc_pgdat_section(struct pglist_data *pgdat)
+sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
+ unsigned long count)
{
unsigned long section_nr;

@@ -286,7 +287,7 @@ sparse_early_usemap_alloc_pgdat_section(
* this problem.
*/
section_nr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
- return alloc_bootmem_section(usemap_size(), section_nr);
+ return alloc_bootmem_section(usemap_size() * count, section_nr);
}

static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
@@ -329,7 +330,8 @@ static void __init check_usemap_section_
}
#else
static unsigned long * __init
-sparse_early_usemap_alloc_pgdat_section(struct pglist_data *pgdat)
+sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
+ unsigned long count)
{
return NULL;
}
@@ -339,27 +341,40 @@ static void __init check_usemap_section_
}
#endif /* CONFIG_MEMORY_HOTREMOVE */

-static unsigned long *__init sparse_early_usemap_alloc(unsigned long pnum)
+static void __init sparse_early_usemaps_alloc_node(unsigned long**usemap_map,
+ unsigned long pnum_begin,
+ unsigned long pnum_end,
+ unsigned long usemap_count, int nodeid)
{
- unsigned long *usemap;
- struct mem_section *ms = __nr_to_section(pnum);
- int nid = sparse_early_nid(ms);
-
- usemap = sparse_early_usemap_alloc_pgdat_section(NODE_DATA(nid));
- if (usemap)
- return usemap;
+ void *usemap;
+ unsigned long pnum;
+ int size = usemap_size();

- usemap = alloc_bootmem_node(NODE_DATA(nid), usemap_size());
+ usemap = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nodeid),
+ usemap_count);
if (usemap) {
- check_usemap_section_nr(nid, usemap);
- return usemap;
+ for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
+ if (!present_section_nr(pnum))
+ continue;
+ usemap_map[pnum] = usemap;
+ usemap += size;
+ }
+ return;
}

- /* Stupid: suppress gcc warning for SPARSEMEM && !NUMA */
- nid = 0;
+ usemap = alloc_bootmem_node(NODE_DATA(nodeid), size * usemap_count);
+ if (usemap) {
+ for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
+ if (!present_section_nr(pnum))
+ continue;
+ usemap_map[pnum] = usemap;
+ usemap += size;
+ check_usemap_section_nr(nodeid, usemap_map[pnum]);
+ }
+ return;
+ }

printk(KERN_WARNING "%s: allocation failed\n", __func__);
- return NULL;
}

#ifndef CONFIG_SPARSEMEM_VMEMMAP
@@ -396,6 +411,7 @@ static struct page __init *sparse_early_
void __attribute__((weak)) __meminit vmemmap_populate_print_last(void)
{
}
+
/*
* Allocate the accumulated non-linear sections, allocate a mem_map
* for each and record the physical to section mapping.
@@ -407,6 +423,9 @@ void __init sparse_init(void)
unsigned long *usemap;
unsigned long **usemap_map;
int size;
+ int nodeid_begin = 0;
+ unsigned long pnum_begin = 0;
+ unsigned long usemap_count;

/*
* map is using big page (aka 2M in x86 64 bit)
@@ -425,10 +444,39 @@ void __init sparse_init(void)
panic("can not allocate usemap_map\n");

for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
+ struct mem_section *ms;
+
+ if (!present_section_nr(pnum))
+ continue;
+ ms = __nr_to_section(pnum);
+ nodeid_begin = sparse_early_nid(ms);
+ pnum_begin = pnum;
+ break;
+ }
+ usemap_count = 1;
+ for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) {
+ struct mem_section *ms;
+ int nodeid;
+
if (!present_section_nr(pnum))
continue;
- usemap_map[pnum] = sparse_early_usemap_alloc(pnum);
+ ms = __nr_to_section(pnum);
+ nodeid = sparse_early_nid(ms);
+ if (nodeid == nodeid_begin) {
+ usemap_count++;
+ continue;
+ }
+ /* ok, we need to take cake of from pnum_begin to pnum - 1*/
+ sparse_early_usemaps_alloc_node(usemap_map, pnum_begin, pnum,
+ usemap_count, nodeid_begin);
+ /* new start, update count etc*/
+ nodeid_begin = nodeid;
+ pnum_begin = pnum;
+ usemap_count = 1;
}
+ /* ok, last chunk */
+ sparse_early_usemaps_alloc_node(usemap_map, pnum_begin, NR_MEM_SECTIONS,
+ usemap_count, nodeid_begin);

for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
if (!present_section_nr(pnum))