From 1b000a5dbeb2f34bc03d45ebdf3f6d24a60c3aed Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Wed, 30 Jan 2008 13:33:25 +0100 Subject: [PATCH] x86: make NUMA work on 32-bit The DISCONTIG memory model on x86 32 bit uses a remap allocator early in boot. The objective is that portions of every node are mapped in to the kernel virtual area (KVA) in place of ZONE_NORMAL so that node-local allocations can be made for pgdat and mem_map structures. With SPARSEMEM, the amount that is set aside is insufficient for all the mem_maps to be allocated. During the boot process, it falls back to using the bootmem allocator. This breaks assumptions that SPARSEMEM makes about the layout of the mem_map in memory and results in a VM_BUG_ON triggering due to pfn_to_page() returning garbage values. This patch only enables the remap allocator for use with DISCONTIG. Without SRAT support, a compile-error occurs because ACPI table parsing functions are only available in x86-64. This patch also adds no-op stubs and prints a warning message. What likely needs to be done is sharing the table parsing functions between 32 and 64 bit if they are compatible. Signed-off-by: Mel Gorman Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/mm/discontig_32.c | 93 ++++++++++++++++++++++++++++++++------ 1 file changed, 78 insertions(+), 15 deletions(-) diff --git a/arch/x86/mm/discontig_32.c b/arch/x86/mm/discontig_32.c index 9f1d02cfde37..04b1d20e2613 100644 --- a/arch/x86/mm/discontig_32.c +++ b/arch/x86/mm/discontig_32.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -103,14 +104,10 @@ extern unsigned long highend_pfn, highstart_pfn; #define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE) -static unsigned long node_remap_start_pfn[MAX_NUMNODES]; unsigned long node_remap_size[MAX_NUMNODES]; -static unsigned long node_remap_offset[MAX_NUMNODES]; static void *node_remap_start_vaddr[MAX_NUMNODES]; void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags); -static void *node_remap_end_vaddr[MAX_NUMNODES]; -static void *node_remap_alloc_vaddr[MAX_NUMNODES]; static unsigned long kva_start_pfn; static unsigned long kva_pages; /* @@ -167,6 +164,22 @@ static void __init allocate_pgdat(int nid) } } +#ifdef CONFIG_DISCONTIGMEM +/* + * In the discontig memory model, a portion of the kernel virtual area (KVA) + * is reserved and portions of nodes are mapped using it. This is to allow + * node-local memory to be allocated for structures that would normally require + * ZONE_NORMAL. The memory is allocated with alloc_remap() and callers + * should be prepared to allocate from the bootmem allocator instead. This KVA + * mechanism is incompatible with SPARSEMEM as it makes assumptions about the + * layout of memory that are broken if alloc_remap() succeeds for some of the + * map and fails for others + */ +static unsigned long node_remap_start_pfn[MAX_NUMNODES]; +static void *node_remap_end_vaddr[MAX_NUMNODES]; +static void *node_remap_alloc_vaddr[MAX_NUMNODES]; +static unsigned long node_remap_offset[MAX_NUMNODES]; + void *alloc_remap(int nid, unsigned long size) { void *allocation = node_remap_alloc_vaddr[nid]; @@ -263,6 +276,40 @@ static unsigned long calculate_numa_remap_pages(void) return reserve_pages; } +static void init_remap_allocator(int nid) +{ + node_remap_start_vaddr[nid] = pfn_to_kaddr( + kva_start_pfn + node_remap_offset[nid]); + node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] + + (node_remap_size[nid] * PAGE_SIZE); + node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] + + ALIGN(sizeof(pg_data_t), PAGE_SIZE); + + printk ("node %d will remap to vaddr %08lx - %08lx\n", nid, + (ulong) node_remap_start_vaddr[nid], + (ulong) pfn_to_kaddr(highstart_pfn + + node_remap_offset[nid] + node_remap_size[nid])); +} +#else +void *alloc_remap(int nid, unsigned long size) +{ + return NULL; +} + +static unsigned long calculate_numa_remap_pages(void) +{ + return 0; +} + +static void init_remap_allocator(int nid) +{ +} + +void __init remap_numa_kva(void) +{ +} +#endif /* CONFIG_DISCONTIGMEM */ + extern void setup_bootmem_allocator(void); unsigned long __init setup_memory(void) { @@ -326,19 +373,9 @@ unsigned long __init setup_memory(void) printk("Low memory ends at vaddr %08lx\n", (ulong) pfn_to_kaddr(max_low_pfn)); for_each_online_node(nid) { - node_remap_start_vaddr[nid] = pfn_to_kaddr( - kva_start_pfn + node_remap_offset[nid]); - /* Init the node remap allocator */ - node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] + - (node_remap_size[nid] * PAGE_SIZE); - node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] + - ALIGN(sizeof(pg_data_t), PAGE_SIZE); + init_remap_allocator(nid); allocate_pgdat(nid); - printk ("node %d will remap to vaddr %08lx - %08lx\n", nid, - (ulong) node_remap_start_vaddr[nid], - (ulong) pfn_to_kaddr(highstart_pfn - + node_remap_offset[nid] + node_remap_size[nid])); } printk("High memory starts at vaddr %08lx\n", (ulong) pfn_to_kaddr(highstart_pfn)); @@ -439,3 +476,29 @@ int memory_add_physaddr_to_nid(u64 addr) EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); #endif + +#ifndef CONFIG_HAVE_ARCH_PARSE_SRAT +/* + * XXX FIXME: Make SLIT table parsing available to 32-bit NUMA + * + * These stub functions are needed to compile 32-bit NUMA when SRAT is + * not set. There are functions in srat_64.c for parsing this table + * and it may be possible to make them common functions. + */ +void acpi_numa_slit_init (struct acpi_table_slit *slit) +{ + printk(KERN_INFO "ACPI: No support for parsing SLIT table\n"); +} + +void acpi_numa_processor_affinity_init (struct acpi_srat_cpu_affinity *pa) +{ +} + +void acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma) +{ +} + +void acpi_numa_arch_fixup(void) +{ +} +#endif /* CONFIG_HAVE_ARCH_PARSE_SRAT */ -- 2.20.1