Revert recent NUMA and pgd_index() fixes, since they show regressions.

People are investigating.

Cset exclude: davem@sunset.davemloft.net|ChangeSet|20050315051617|44508
Cset exclude: kravetz@us.ibm.com[torvalds]|ChangeSet|20050314002422|18516

arch/ppc64/mm/numa.c

@@ -40,6 +40,7 @@ int nr_cpus_in_node[MAX_NUMNODES] = { [0 ... (MAX_NUMNODES -1)] = 0};
 
 struct pglist_data *node_data[MAX_NUMNODES];
 bootmem_data_t __initdata plat_node_bdata[MAX_NUMNODES];
+static unsigned long node0_io_hole_size;
 static int min_common_depth;
 
 /*
@@ -48,8 +49,7 @@ static int min_common_depth;
  */
 static struct {
 	unsigned long node_start_pfn;
-	unsigned long node_end_pfn;
-	unsigned long node_present_pages;
+	unsigned long node_spanned_pages;
 } init_node_data[MAX_NUMNODES] __initdata;
 
 EXPORT_SYMBOL(node_data);
@@ -186,31 +186,14 @@ static int __init find_min_common_depth(void)
 	return depth;
 }
 
-static int __init get_mem_addr_cells(void)
-{
-	struct device_node *memory = NULL;
-
-	memory = of_find_node_by_type(memory, "memory");
-	if (!memory)
-		return 0; /* it won't matter */
-	return(prom_n_addr_cells(memory));
-}
-
-static int __init get_mem_size_cells(void)
-{
-	struct device_node *memory = NULL;
-
-	memory = of_find_node_by_type(memory, "memory");
-	if (!memory)
-		return 0; /* it won't matter */
-	return(prom_n_size_cells(memory));
-}
-
-static unsigned long read_n_cells(int n, unsigned int **buf)
+static unsigned long read_cell_ul(struct device_node *device, unsigned int **buf)
 {
+	int i;
 	unsigned long result = 0;
 
-	while (n--) {
+	i = prom_n_size_cells(device);
+	/* bug on i>2 ?? */
+	while (i--) {
 		result = (result << 32) | **buf;
 		(*buf)++;
 	}
@@ -284,7 +267,6 @@ static int __init parse_numa_properties(void)
 {
 	struct device_node *cpu = NULL;
 	struct device_node *memory = NULL;
-	int addr_cells, size_cells;
 	int max_domain = 0;
 	long entries = lmb_end_of_DRAM() >> MEMORY_INCREMENT_SHIFT;
 	unsigned long i;
@@ -331,8 +313,6 @@ static int __init parse_numa_properties(void)
 		}
 	}
 
-	addr_cells = get_mem_addr_cells();
-	size_cells = get_mem_size_cells();
 	memory = NULL;
 	while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
 		unsigned long start;
@@ -349,8 +329,8 @@ 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(addr_cells, &memcell_buf);
-		size = read_n_cells(size_cells, &memcell_buf);
+		start = read_cell_ul(memory, &memcell_buf);
+		size = read_cell_ul(memory, &memcell_buf);
 
 		start = _ALIGN_DOWN(start, MEMORY_INCREMENT);
 		size = _ALIGN_UP(size, MEMORY_INCREMENT);
@@ -368,28 +348,33 @@ static int __init parse_numa_properties(void)
 		if (max_domain < numa_domain)
 			max_domain = numa_domain;
 
-		/*
-		 * Initialize new node struct, or add to an existing one.
+		/* 
+		 * For backwards compatibility, OF splits the first node
+		 * into two regions (the first being 0-4GB). Check for
+		 * this simple case and complain if there is a gap in
+		 * memory
 		 */
-		if (init_node_data[numa_domain].node_end_pfn) {
-			if ((start / PAGE_SIZE) <
-			    init_node_data[numa_domain].node_start_pfn)
-				init_node_data[numa_domain].node_start_pfn =
-					start / PAGE_SIZE;
-			else
-				init_node_data[numa_domain].node_end_pfn =
-					(start / PAGE_SIZE) +
-					(size / PAGE_SIZE);
-
-			init_node_data[numa_domain].node_present_pages +=
+		if (init_node_data[numa_domain].node_spanned_pages) {
+			unsigned long shouldstart =
+				init_node_data[numa_domain].node_start_pfn +
+				init_node_data[numa_domain].node_spanned_pages;
+			if (shouldstart != (start / PAGE_SIZE)) {
+				/* Revert to non-numa for now */
+				printk(KERN_ERR
+				       "WARNING: Unexpected node layout: "
+				       "region start %lx length %lx\n",
+				       start, size);
+				printk(KERN_ERR "NUMA is disabled\n");
+				goto err;
+			}
+			init_node_data[numa_domain].node_spanned_pages +=
 				size / PAGE_SIZE;
 		} else {
 			node_set_online(numa_domain);
 
 			init_node_data[numa_domain].node_start_pfn =
 				start / PAGE_SIZE;
-			init_node_data[numa_domain].node_end_pfn =
-				init_node_data[numa_domain].node_start_pfn +
+			init_node_data[numa_domain].node_spanned_pages =
 				size / PAGE_SIZE;
 		}
 
@@ -406,6 +391,14 @@ static int __init parse_numa_properties(void)
 		node_set_online(i);
 
 	return 0;
+err:
+	/* Something has gone wrong; revert any setup we've done */
+	for_each_node(i) {
+		node_set_offline(i);
+		init_node_data[i].node_start_pfn = 0;
+		init_node_data[i].node_spanned_pages = 0;
+	}
+	return -1;
 }
 
 static void __init setup_nonnuma(void)
@@ -433,11 +426,12 @@ static void __init setup_nonnuma(void)
 	node_set_online(0);
 
 	init_node_data[0].node_start_pfn = 0;
-	init_node_data[0].node_end_pfn = lmb_end_of_DRAM() / PAGE_SIZE;
-	init_node_data[0].node_present_pages = total_ram / PAGE_SIZE;
+	init_node_data[0].node_spanned_pages = lmb_end_of_DRAM() / PAGE_SIZE;
 
 	for (i = 0 ; i < top_of_ram; i += MEMORY_INCREMENT)
 		numa_memory_lookup_table[i >> MEMORY_INCREMENT_SHIFT] = 0;
+
+	node0_io_hole_size = top_of_ram - total_ram;
 }
 
 static void __init dump_numa_topology(void)
@@ -518,8 +512,6 @@ static unsigned long careful_allocation(int nid, unsigned long size,
 void __init do_init_bootmem(void)
 {
 	int nid;
-	int addr_cells, size_cells;
-	struct device_node *memory = NULL;
 	static struct notifier_block ppc64_numa_nb = {
 		.notifier_call = cpu_numa_callback,
 		.priority = 1 /* Must run before sched domains notifier. */
@@ -543,7 +535,7 @@ void __init do_init_bootmem(void)
 		unsigned long bootmap_pages;
 
 		start_paddr = init_node_data[nid].node_start_pfn * PAGE_SIZE;
-		end_paddr = init_node_data[nid].node_end_pfn * PAGE_SIZE;
+		end_paddr = start_paddr + (init_node_data[nid].node_spanned_pages * PAGE_SIZE);
 
 		/* Allocate the node structure node local if possible */
 		NODE_DATA(nid) = (struct pglist_data *)careful_allocation(nid,
@@ -559,9 +551,9 @@ void __init do_init_bootmem(void)
 		NODE_DATA(nid)->node_start_pfn =
 			init_node_data[nid].node_start_pfn;
 		NODE_DATA(nid)->node_spanned_pages =
-			end_paddr - start_paddr;
+			init_node_data[nid].node_spanned_pages;
 
-		if (NODE_DATA(nid)->node_spanned_pages == 0)
+		if (init_node_data[nid].node_spanned_pages == 0)
   			continue;
 
   		dbg("start_paddr = %lx\n", start_paddr);
@@ -580,50 +572,33 @@ void __init do_init_bootmem(void)
 				  start_paddr >> PAGE_SHIFT,
 				  end_paddr >> PAGE_SHIFT);
 
-		/*
-		 * We need to do another scan of all memory sections to
-		 * associate memory with the correct node.
-		 */
-		addr_cells = get_mem_addr_cells();
-		size_cells = get_mem_size_cells();
-		memory = NULL;
-		while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
-			unsigned long mem_start, mem_size;
-			int numa_domain;
-			unsigned int *memcell_buf;
-			unsigned int len;
-
-			memcell_buf = (unsigned int *)get_property(memory, "reg", &len);
-			if (!memcell_buf || len <= 0)
-				continue;
-
-			mem_start = read_n_cells(addr_cells, &memcell_buf);
-			mem_size = read_n_cells(size_cells, &memcell_buf);
-			numa_domain = of_node_numa_domain(memory);
-
-			if (numa_domain != nid)
-				continue;
-
-			if (mem_start < end_paddr &&
-			    (mem_start+mem_size) > start_paddr) {
-				/* should be no overlaps ! */
-				dbg("free_bootmem %lx %lx\n", mem_start, mem_size);
-				free_bootmem_node(NODE_DATA(nid), mem_start,
-						  mem_size);
+		for (i = 0; i < lmb.memory.cnt; i++) {
+			unsigned long physbase, size;
+
+			physbase = lmb.memory.region[i].physbase;
+			size = lmb.memory.region[i].size;
+
+			if (physbase < end_paddr &&
+			    (physbase+size) > start_paddr) {
+				/* overlaps */
+				if (physbase < start_paddr) {
+					size -= start_paddr - physbase;
+					physbase = start_paddr;
+				}
+
+				if (size > end_paddr - physbase)
+					size = end_paddr - physbase;
+
+				dbg("free_bootmem %lx %lx\n", physbase, size);
+				free_bootmem_node(NODE_DATA(nid), physbase,
+						  size);
 			}
 		}
 
-		/*
-		 * Mark reserved regions on this node
-		 */
 		for (i = 0; i < lmb.reserved.cnt; i++) {
 			unsigned long physbase = lmb.reserved.region[i].physbase;
 			unsigned long size = lmb.reserved.region[i].size;
 
-			if (pa_to_nid(physbase) != nid &&
-			    pa_to_nid(physbase+size-1) != nid)
-				continue;
-
 			if (physbase < end_paddr &&
 			    (physbase+size) > start_paddr) {
 				/* overlaps */
@@ -657,12 +632,13 @@ void __init paging_init(void)
 		unsigned long start_pfn;
 		unsigned long end_pfn;
 
-		start_pfn = init_node_data[nid].node_start_pfn;
-		end_pfn = init_node_data[nid].node_end_pfn;
+		start_pfn = plat_node_bdata[nid].node_boot_start >> PAGE_SHIFT;
+		end_pfn = plat_node_bdata[nid].node_low_pfn;
 
 		zones_size[ZONE_DMA] = end_pfn - start_pfn;
-		zholes_size[ZONE_DMA] = zones_size[ZONE_DMA] -
-			init_node_data[nid].node_present_pages;
+		zholes_size[ZONE_DMA] = 0;
+		if (nid == 0)
+			zholes_size[ZONE_DMA] = node0_io_hole_size >> PAGE_SHIFT;
 
 		dbg("free_area_init node %d %lx %lx (hole: %lx)\n", nid,
 		    zones_size[ZONE_DMA], start_pfn, zholes_size[ZONE_DMA]);

mm/memory.c

@@ -182,19 +182,15 @@ void clear_page_range(struct mmu_gather *tlb,
 				unsigned long addr, unsigned long end)
 {
 	pgd_t *pgd;
-	unsigned long i, next;
+	unsigned long next;
 
 	pgd = pgd_offset(tlb->mm, addr);
-	for (i = pgd_index(addr); i <= pgd_index(end-1); i++) {
+	do {
 		next = pgd_addr_end(addr, end);
 		if (pgd_none_or_clear_bad(pgd))
 			continue;
 		clear_pud_range(tlb, pgd, addr, next);
-		pgd++;
-		addr = next;
-		if (addr == end)
-			break;
-	}
+	} while (pgd++, addr = next, addr != end);
 }
 
 pte_t fastcall * pte_alloc_map(struct mm_struct *mm, pmd_t *pmd, unsigned long address)