X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;ds=sidebyside;f=mm%2Fsparse.c;h=6ce4aab69e9974aea1838092efc26601ea7598b4;hb=73834d6f90f6833663f9effd4cf9b79b63bc36e1;hp=7a3650923d9a8f6a5b4b959982f658d5032cd923;hpb=2dbb51c49f4fecb8330e43247a0edfbc4b2b8974;p=safe%2Fjmp%2Flinux-2.6

diff --git a/mm/sparse.c b/mm/sparse.c
index 7a36509..6ce4aab 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -12,7 +12,6 @@
 #include <asm/dma.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
-#include "internal.h"
 
 /*
  * Permanent SPARSEMEM data:
@@ -63,9 +62,12 @@ static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
 	unsigned long array_size = SECTIONS_PER_ROOT *
 				   sizeof(struct mem_section);
 
-	if (slab_is_available())
-		section = kmalloc_node(array_size, GFP_KERNEL, nid);
-	else
+	if (slab_is_available()) {
+		if (node_state(nid, N_HIGH_MEMORY))
+			section = kmalloc_node(array_size, GFP_KERNEL, nid);
+		else
+			section = kmalloc(array_size, GFP_KERNEL);
+	} else
 		section = alloc_bootmem_node(NODE_DATA(nid), array_size);
 
 	if (section)
@@ -165,9 +167,7 @@ void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn,
 		WARN_ON_ONCE(1);
 		*start_pfn = max_sparsemem_pfn;
 		*end_pfn = max_sparsemem_pfn;
-	}
-
-	if (*end_pfn > max_sparsemem_pfn) {
+	} else if (*end_pfn > max_sparsemem_pfn) {
 		mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
 			"End of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
 			*start_pfn, *end_pfn, max_sparsemem_pfn);
@@ -269,16 +269,92 @@ static unsigned long *__kmalloc_section_usemap(void)
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
 
+#ifdef CONFIG_MEMORY_HOTREMOVE
+static unsigned long * __init
+sparse_early_usemap_alloc_pgdat_section(struct pglist_data *pgdat)
+{
+	unsigned long section_nr;
+
+	/*
+	 * A page may contain usemaps for other sections preventing the
+	 * page being freed and making a section unremovable while
+	 * other sections referencing the usemap retmain active. Similarly,
+	 * a pgdat can prevent a section being removed. If section A
+	 * contains a pgdat and section B contains the usemap, both
+	 * sections become inter-dependent. This allocates usemaps
+	 * from the same section as the pgdat where possible to avoid
+	 * this problem.
+	 */
+	section_nr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
+	return alloc_bootmem_section(usemap_size(), section_nr);
+}
+
+static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
+{
+	unsigned long usemap_snr, pgdat_snr;
+	static unsigned long old_usemap_snr = NR_MEM_SECTIONS;
+	static unsigned long old_pgdat_snr = NR_MEM_SECTIONS;
+	struct pglist_data *pgdat = NODE_DATA(nid);
+	int usemap_nid;
+
+	usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT);
+	pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
+	if (usemap_snr == pgdat_snr)
+		return;
+
+	if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
+		/* skip redundant message */
+		return;
+
+	old_usemap_snr = usemap_snr;
+	old_pgdat_snr = pgdat_snr;
+
+	usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
+	if (usemap_nid != nid) {
+		printk(KERN_INFO
+		       "node %d must be removed before remove section %ld\n",
+		       nid, usemap_snr);
+		return;
+	}
+	/*
+	 * There is a circular dependency.
+	 * Some platforms allow un-removable section because they will just
+	 * gather other removable sections for dynamic partitioning.
+	 * Just notify un-removable section's number here.
+	 */
+	printk(KERN_INFO "Section %ld and %ld (node %d)", usemap_snr,
+	       pgdat_snr, nid);
+	printk(KERN_CONT
+	       " have a circular dependency on usemap and pgdat allocations\n");
+}
+#else
+static unsigned long * __init
+sparse_early_usemap_alloc_pgdat_section(struct pglist_data *pgdat)
+{
+	return NULL;
+}
+
+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)
 {
 	unsigned long *usemap;
 	struct mem_section *ms = __nr_to_section(pnum);
 	int nid = sparse_early_nid(ms);
 
-	usemap = alloc_bootmem_node(NODE_DATA(nid), usemap_size());
+	usemap = sparse_early_usemap_alloc_pgdat_section(NODE_DATA(nid));
 	if (usemap)
 		return usemap;
 
+	usemap = alloc_bootmem_node(NODE_DATA(nid), usemap_size());
+	if (usemap) {
+		check_usemap_section_nr(nid, usemap);
+		return usemap;
+	}
+
 	/* Stupid: suppress gcc warning for SPARSEMEM && !NUMA */
 	nid = 0;
 
@@ -301,7 +377,7 @@ struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
 }
 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
 
-struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
+static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
 {
 	struct page *map;
 	struct mem_section *ms = __nr_to_section(pnum);
@@ -495,7 +571,7 @@ static void free_section_usemap(struct page *memmap, unsigned long *usemap)
  * set.  If this is <=0, then that means that the passed-in
  * map was not consumed and must be freed.
  */
-int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
+int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
 			   int nr_pages)
 {
 	unsigned long section_nr = pfn_to_section_nr(start_pfn);