#include <linux/firmware-map.h>
#include <linux/stop_machine.h>
#include <linux/hugetlb.h>
+#include <linux/memblock.h>
#include <asm/tlbflush.h>
static void grow_pgdat_span(struct pglist_data *pgdat, unsigned long start_pfn,
unsigned long end_pfn)
{
- unsigned long old_pgdat_end_pfn =
- pgdat->node_start_pfn + pgdat->node_spanned_pages;
+ unsigned long old_pgdat_end_pfn = pgdat_end_pfn(pgdat);
if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
pgdat->node_start_pfn = start_pfn;
static int __meminit __add_section(int nid, struct zone *zone,
unsigned long phys_start_pfn)
{
- int nr_pages = PAGES_PER_SECTION;
int ret;
if (pfn_valid(phys_start_pfn))
return -EEXIST;
- ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
+ ret = sparse_add_one_section(zone, phys_start_pfn);
if (ret < 0)
return ret;
static void shrink_pgdat_span(struct pglist_data *pgdat,
unsigned long start_pfn, unsigned long end_pfn)
{
- unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
- unsigned long pgdat_end_pfn =
- pgdat->node_start_pfn + pgdat->node_spanned_pages;
+ unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
+ unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */
+ unsigned long pgdat_end_pfn = p;
unsigned long pfn;
struct mem_section *ms;
int nid = pgdat->node_id;
arg.nr_pages = nr_pages;
node_states_check_changes_online(nr_pages, zone, &arg);
- nid = page_to_nid(pfn_to_page(pfn));
+ nid = pfn_to_nid(pfn);
ret = memory_notify(MEM_GOING_ONLINE, &arg);
ret = notifier_to_errno(ret);
}
-/*
+/**
+ * try_online_node - online a node if offlined
+ *
* called by cpu_up() to online a node without onlined memory.
*/
-int mem_online_node(int nid)
+int try_online_node(int nid)
{
pg_data_t *pgdat;
int ret;
+ if (node_online(nid))
+ return 0;
+
lock_memory_hotplug();
pgdat = hotadd_new_pgdat(nid, 0);
if (!pgdat) {
+ pr_err("Cannot online node %d due to NULL pgdat\n", nid);
ret = -ENOMEM;
goto out;
}
ret = register_one_node(nid);
BUG_ON(ret);
+ if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
+ mutex_lock(&zonelists_mutex);
+ build_all_zonelists(NULL, NULL);
+ mutex_unlock(&zonelists_mutex);
+ }
+
out:
unlock_memory_hotplug();
return ret;
}
#endif /* CONFIG_MOVABLE_NODE */
+static int __init cmdline_parse_movable_node(char *p)
+{
+#ifdef CONFIG_MOVABLE_NODE
+ /*
+ * Memory used by the kernel cannot be hot-removed because Linux
+ * cannot migrate the kernel pages. When memory hotplug is
+ * enabled, we should prevent memblock from allocating memory
+ * for the kernel.
+ *
+ * ACPI SRAT records all hotpluggable memory ranges. But before
+ * SRAT is parsed, we don't know about it.
+ *
+ * The kernel image is loaded into memory at very early time. We
+ * cannot prevent this anyway. So on NUMA system, we set any
+ * node the kernel resides in as un-hotpluggable.
+ *
+ * Since on modern servers, one node could have double-digit
+ * gigabytes memory, we can assume the memory around the kernel
+ * image is also un-hotpluggable. So before SRAT is parsed, just
+ * allocate memory near the kernel image to try the best to keep
+ * the kernel away from hotpluggable memory.
+ */
+ memblock_set_bottom_up(true);
+#else
+ pr_warn("movable_node option not supported\n");
+#endif
+ return 0;
+}
+early_param("movable_node", cmdline_parse_movable_node);
+
/* check which state of node_states will be changed when offline memory */
static void node_states_check_changes_offline(unsigned long nr_pages,
struct zone *zone, struct memory_notify *arg)
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-static int is_memblock_offlined_cb(struct memory_block *mem, void *arg)
+static int check_memblock_offlined_cb(struct memory_block *mem, void *arg)
{
int ret = !is_memblock_offlined(mem);
* if this is not the case.
*/
ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
- is_memblock_offlined_cb);
+ check_memblock_offlined_cb);
if (ret) {
unlock_memory_hotplug();
BUG();