[PATCH] powerpc: numa placement for dynamically added memory

This places dynamically added memory within the appropriate
numa node.  A new routine hot_add_scn_to_nid() replicates most of
the memory scanning code in parse_numa_properties().

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index ed6ed2e..5e5bff5 100644 (file)
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -114,18 +114,17 @@ void online_page(struct page *page)
        num_physpages++;
 }
 
-/*
- * This works only for the non-NUMA case.  Later, we'll need a lookup
- * to convert from real physical addresses to nid, that doesn't use
- * pfn_to_nid().
- */
 int __devinit add_memory(u64 start, u64 size)
 {
-       struct pglist_data *pgdata = NODE_DATA(0);
+       struct pglist_data *pgdata;
        struct zone *zone;
+       int nid;
        unsigned long start_pfn = start >> PAGE_SHIFT;
        unsigned long nr_pages = size >> PAGE_SHIFT;
 
+       nid = hot_add_scn_to_nid(start);
+       pgdata = NODE_DATA(nid);
+
        start += KERNELBASE;
        create_section_mapping(start, start + size);
 

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index e812d3d..40c99de 100644 (file)
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -37,6 +37,7 @@ EXPORT_SYMBOL(node_data);
 
 static bootmem_data_t __initdata plat_node_bdata[MAX_NUMNODES];
 static int min_common_depth;
+static int n_mem_addr_cells, n_mem_size_cells;
 
 /*
  * We need somewhere to store start/end/node for each region until we have
@@ -267,7 +268,7 @@ static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
        of_node_put(memory);
 }
 
-static unsigned long __init read_n_cells(int n, unsigned int **buf)
+static unsigned long __devinit read_n_cells(int n, unsigned int **buf)
 {
        unsigned long result = 0;
 
@@ -374,7 +375,6 @@ static int __init parse_numa_properties(void)
 {
        struct device_node *cpu = NULL;
        struct device_node *memory = NULL;
-       int n_addr_cells, n_size_cells;
        int max_domain;
        unsigned long i;
 
@@ -413,7 +413,7 @@ static int __init parse_numa_properties(void)
                }
        }
 
-       get_n_mem_cells(&n_addr_cells, &n_size_cells);
+       get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
        memory = NULL;
        while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
                unsigned long start;
@@ -430,8 +430,8 @@ static int __init parse_numa_properties(void)
                ranges = memory->n_addrs;
 new_range:
                /* these are order-sensitive, and modify the buffer pointer */
-               start = read_n_cells(n_addr_cells, &memcell_buf);
-               size = read_n_cells(n_size_cells, &memcell_buf);
+               start = read_n_cells(n_mem_addr_cells, &memcell_buf);
+               size = read_n_cells(n_mem_size_cells, &memcell_buf);
 
                numa_domain = of_node_numa_domain(memory);
 
@@ -717,3 +717,50 @@ static int __init early_numa(char *p)
        return 0;
 }
 early_param("numa", early_numa);
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+/*
+ * Find the node associated with a hot added memory section.  Section
+ * corresponds to a SPARSEMEM section, not an LMB.  It is assumed that
+ * sections are fully contained within a single LMB.
+ */
+int hot_add_scn_to_nid(unsigned long scn_addr)
+{
+       struct device_node *memory = NULL;
+
+       if (!numa_enabled || (min_common_depth < 0))
+               return 0;
+
+       while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
+               unsigned long start, size;
+               int numa_domain, ranges;
+               unsigned int *memcell_buf;
+               unsigned int len;
+
+               memcell_buf = (unsigned int *)get_property(memory, "reg", &len);
+               if (!memcell_buf || len <= 0)
+                       continue;
+
+               ranges = memory->n_addrs;       /* ranges in cell */
+ha_new_range:
+               start = read_n_cells(n_mem_addr_cells, &memcell_buf);
+               size = read_n_cells(n_mem_size_cells, &memcell_buf);
+               numa_domain = of_node_numa_domain(memory);
+
+               /* Domains not present at boot default to 0 */
+               if (!node_online(numa_domain))
+                       numa_domain = any_online_node(NODE_MASK_ALL);
+
+               if ((scn_addr >= start) && (scn_addr < (start + size))) {
+                       of_node_put(memory);
+                       return numa_domain;
+               }
+
+               if (--ranges)           /* process all ranges in cell */
+                       goto ha_new_range;
+       }
+
+       BUG();  /* section address should be found above */
+       return 0;
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */

diff --git a/include/asm-powerpc/sparsemem.h b/include/asm-powerpc/sparsemem.h
index ba1b34f..c3f17d4 100644 (file)
--- a/include/asm-powerpc/sparsemem.h
+++ b/include/asm-powerpc/sparsemem.h
@@ -13,6 +13,14 @@
 
 #ifdef CONFIG_MEMORY_HOTPLUG
 extern void create_section_mapping(unsigned long start, unsigned long end);
+#ifdef CONFIG_NUMA
+extern int hot_add_scn_to_nid(unsigned long scn_addr);
+#else
+static inline int hot_add_scn_to_nid(unsigned long scn_addr)
+{
+       return 0;
+}
+#endif /* CONFIG_NUMA */
 #endif /* CONFIG_MEMORY_HOTPLUG */
 
 #endif /* CONFIG_SPARSEMEM */