sparsemem: Put usemap for one node together

Could save some buffer space 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>
LKML-Reference: <1265793639-15071-18-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 66 insertions, 18 deletions

diff --git a/mm/sparse.c b/mm/sparse.c
index 6ce4aab69e99..0cdaf0b58457 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -271,7 +271,8 @@ static unsigned long *__kmalloc_section_usemap(void)
 
 #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(struct pglist_data *pgdat)
          * 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_nr(int nid, unsigned long *usemap)
 }
 #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_nr(int nid, unsigned long *usemap)
 }
 #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_mem_map_alloc(unsigned long pnum)
 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;
-                usemap_map[pnum] = sparse_early_usemap_alloc(pnum);
+                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;
+                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))