From 8ee2debce32412118cf8c239e0026ace56ea1425 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Fri, 25 Sep 2009 15:20:00 -0700 Subject: x86: Export k8 physical topology To eventually interleave emulated nodes over physical nodes, we need to know the physical topology of the machine without actually registering it. This does the k8 node setup in two parts: detection and registration. NUMA emulation can then used the physical topology detected to setup the address ranges of emulated nodes accordingly. If emulation isn't used, the k8 nodes are registered as normal. Two formals are added to the x86 NUMA setup functions: `acpi' and `k8'. These represent whether ACPI or K8 NUMA has been detected; both cannot be true at the same time. This specifies to the NUMA emulation code whether an underlying physical NUMA topology exists and which interface to use. This patch deals solely with separating the k8 setup path into Northbridge detection and registration steps and leaves the ACPI changes for a subsequent patch. The `acpi' formal is added here, however, to avoid touching all the header files again in the next patch. This approach also ensures emulated nodes will not span physical nodes so the true memory latency is not misrepresented. k8_get_nodes() may now be used to export the k8 physical topology of the machine for NUMA emulation. Signed-off-by: David Rientjes Cc: Andreas Herrmann Cc: Yinghai Lu Cc: Balbir Singh Cc: Ankita Garg Cc: Len Brown LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/mm/numa_64.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86/mm/numa_64.c') diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index 459913beac71..dad5f42dd359 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -524,7 +524,8 @@ out: } #endif /* CONFIG_NUMA_EMU */ -void __init initmem_init(unsigned long start_pfn, unsigned long last_pfn) +void __init initmem_init(unsigned long start_pfn, unsigned long last_pfn, + int acpi, int k8) { int i; @@ -547,8 +548,7 @@ void __init initmem_init(unsigned long start_pfn, unsigned long last_pfn) #endif #ifdef CONFIG_K8_NUMA - if (!numa_off && !k8_scan_nodes(start_pfn< Date: Fri, 25 Sep 2009 15:20:04 -0700 Subject: x86: Export srat physical topology This is the counterpart to "x86: export k8 physical topology" for SRAT. It is not as invasive because the acpi code already seperates node setup into detection and registration steps, with the exception of registering e820 active regions in acpi_numa_memory_affinity_init(). This is now moved to acpi_scan_nodes() if NUMA emulation is disabled or deferred. acpi_numa_init() now returns a value which specifies whether an underlying SRAT was located. If so, that topology can be used by the emulation code to interleave emulated nodes over physical nodes or to register the nodes for ACPI. acpi_get_nodes() may now be used to export the srat physical topology of the machine for NUMA emulation. Signed-off-by: David Rientjes Cc: Andreas Herrmann Cc: Yinghai Lu Cc: Balbir Singh Cc: Ankita Garg Cc: Len Brown LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/include/asm/acpi.h | 1 + arch/x86/kernel/setup.c | 5 +++-- arch/x86/mm/numa_64.c | 4 ++-- arch/x86/mm/srat_64.c | 28 +++++++++++++++++++++------- drivers/acpi/numa.c | 10 ++++++---- 5 files changed, 33 insertions(+), 15 deletions(-) (limited to 'arch/x86/mm/numa_64.c') diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h index 4518dc500903..e3d4a0daff57 100644 --- a/arch/x86/include/asm/acpi.h +++ b/arch/x86/include/asm/acpi.h @@ -158,6 +158,7 @@ struct bootnode; #ifdef CONFIG_ACPI_NUMA extern int acpi_numa; +extern int acpi_get_nodes(struct bootnode *physnodes); extern int acpi_scan_nodes(unsigned long start, unsigned long end); #define NR_NODE_MEMBLKS (MAX_NUMNODES*2) extern void acpi_fake_nodes(const struct bootnode *fake_nodes, diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index fda0032c25c6..f89141982702 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -938,11 +938,12 @@ void __init setup_arch(char **cmdline_p) /* * Parse SRAT to discover nodes. */ - acpi_numa_init(); + acpi = acpi_numa_init(); #endif #ifdef CONFIG_K8_NUMA - k8 = !k8_numa_init(0, max_pfn); + if (!acpi) + k8 = !k8_numa_init(0, max_pfn); #endif initmem_init(0, max_pfn, acpi, k8); diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index dad5f42dd359..d1a3d94efc8e 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -540,8 +540,8 @@ void __init initmem_init(unsigned long start_pfn, unsigned long last_pfn, #endif #ifdef CONFIG_ACPI_NUMA - if (!numa_off && !acpi_scan_nodes(start_pfn << PAGE_SHIFT, - last_pfn << PAGE_SHIFT)) + if (!numa_off && acpi && !acpi_scan_nodes(start_pfn << PAGE_SHIFT, + last_pfn << PAGE_SHIFT)) return; nodes_clear(node_possible_map); nodes_clear(node_online_map); diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c index dbb5381f7b3b..891cbe65b2d5 100644 --- a/arch/x86/mm/srat_64.c +++ b/arch/x86/mm/srat_64.c @@ -290,8 +290,6 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma) printk(KERN_INFO "SRAT: Node %u PXM %u %lx-%lx\n", node, pxm, start, end); - e820_register_active_regions(node, start >> PAGE_SHIFT, - end >> PAGE_SHIFT); if (ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) { update_nodes_add(node, start, end); @@ -338,6 +336,19 @@ static int __init nodes_cover_memory(const struct bootnode *nodes) void __init acpi_numa_arch_fixup(void) {} +int __init acpi_get_nodes(struct bootnode *physnodes) +{ + int i; + int ret = 0; + + for_each_node_mask(i, nodes_parsed) { + physnodes[ret].start = nodes[i].start; + physnodes[ret].end = nodes[i].end; + ret++; + } + return ret; +} + /* Use the information discovered above to actually set up the nodes. */ int __init acpi_scan_nodes(unsigned long start, unsigned long end) { @@ -350,11 +361,6 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end) for (i = 0; i < MAX_NUMNODES; i++) cutoff_node(i, start, end); - if (!nodes_cover_memory(nodes)) { - bad_srat(); - return -1; - } - memnode_shift = compute_hash_shift(node_memblk_range, num_node_memblks, memblk_nodeid); if (memnode_shift < 0) { @@ -364,6 +370,14 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end) return -1; } + for_each_node_mask(i, nodes_parsed) + e820_register_active_regions(i, nodes[i].start >> PAGE_SHIFT, + nodes[i].end >> PAGE_SHIFT); + if (!nodes_cover_memory(nodes)) { + bad_srat(); + return -1; + } + /* Account for nodes with cpus and no memory */ nodes_or(node_possible_map, nodes_parsed, cpu_nodes_parsed); diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c index 202dd0c976a3..2be2fb66204e 100644 --- a/drivers/acpi/numa.c +++ b/drivers/acpi/numa.c @@ -283,22 +283,24 @@ acpi_table_parse_srat(enum acpi_srat_type id, int __init acpi_numa_init(void) { + int ret = 0; + /* SRAT: Static Resource Affinity Table */ if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) { acpi_table_parse_srat(ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY, acpi_parse_x2apic_affinity, NR_CPUS); acpi_table_parse_srat(ACPI_SRAT_TYPE_CPU_AFFINITY, acpi_parse_processor_affinity, NR_CPUS); - acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, - acpi_parse_memory_affinity, - NR_NODE_MEMBLKS); + ret = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, + acpi_parse_memory_affinity, + NR_NODE_MEMBLKS); } /* SLIT: System Locality Information Table */ acpi_table_parse(ACPI_SIG_SLIT, acpi_parse_slit); acpi_numa_arch_fixup(); - return 0; + return ret; } int acpi_get_pxm(acpi_handle h) -- cgit v1.2.3 From adc1938994f7f1112d335d998b5218b0aa680ad6 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Fri, 25 Sep 2009 15:20:09 -0700 Subject: x86: Interleave emulated nodes over physical nodes Add interleaved NUMA emulation support This patch interleaves emulated nodes over the system's physical nodes. This is required for interleave optimizations since mempolicies, for example, operate by iterating over a nodemask and act without knowledge of node distances. It can also be used for testing memory latencies and NUMA bugs in the kernel. There're a couple of ways to do this: - divide the number of emulated nodes by the number of physical nodes and allocate the result on each physical node, or - allocate each successive emulated node on a different physical node until all memory is exhausted. The disadvantage of the first option is, depending on the asymmetry in node capacities of each physical node, emulated nodes may substantially differ in size on a particular physical node compared to another. The disadvantage of the second option is, also depending on the asymmetry in node capacities of each physical node, there may be more emulated nodes allocated on a single physical node as another. This patch implements the second option; we sacrifice the possibility that we may have slightly more emulated nodes on a particular physical node compared to another in lieu of node size asymmetry. [ Note that "node capacity" of a physical node is not only a function of its addressable range, but also is affected by subtracting out the amount of reserved memory over that range. NUMA emulation only deals with available, non-reserved memory quantities. ] We ensure there is at least a minimal amount of available memory allocated to each node. We also make sure that at least this amount of available memory is available in ZONE_DMA32 for any node that includes both ZONE_DMA32 and ZONE_NORMAL. This patch also cleans the emulation code up by no longer passing the statically allocated struct bootnode array among the various functions. This init.data array is not allocated on the stack since it may be very large and thus it may be accessed at file scope. The WARN_ON() for nodes_cover_memory() when faking proximity domains is removed since it relies on successive nodes always having greater start addresses than previous nodes; with interleaving this is no longer always true. Signed-off-by: David Rientjes Cc: Linus Torvalds Cc: Andreas Herrmann Cc: Yinghai Lu Cc: Balbir Singh Cc: Ankita Garg Cc: Len Brown LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/mm/numa_64.c | 211 +++++++++++++++++++++++++++++++++++++++++++------- arch/x86/mm/srat_64.c | 1 - 2 files changed, 184 insertions(+), 28 deletions(-) (limited to 'arch/x86/mm/numa_64.c') diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index d1a3d94efc8e..086f98a66d80 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -306,8 +306,71 @@ void __init numa_init_array(void) #ifdef CONFIG_NUMA_EMU /* Numa emulation */ +static struct bootnode nodes[MAX_NUMNODES] __initdata; +static struct bootnode physnodes[MAX_NUMNODES] __initdata; static char *cmdline __initdata; +static int __init setup_physnodes(unsigned long start, unsigned long end, + int acpi, int k8) +{ + int nr_nodes = 0; + int ret = 0; + int i; + +#ifdef CONFIG_ACPI_NUMA + if (acpi) + nr_nodes = acpi_get_nodes(physnodes); +#endif +#ifdef CONFIG_K8_NUMA + if (k8) + nr_nodes = k8_get_nodes(physnodes); +#endif + /* + * Basic sanity checking on the physical node map: there may be errors + * if the SRAT or K8 incorrectly reported the topology or the mem= + * kernel parameter is used. + */ + for (i = 0; i < nr_nodes; i++) { + if (physnodes[i].start == physnodes[i].end) + continue; + if (physnodes[i].start > end) { + physnodes[i].end = physnodes[i].start; + continue; + } + if (physnodes[i].end < start) { + physnodes[i].start = physnodes[i].end; + continue; + } + if (physnodes[i].start < start) + physnodes[i].start = start; + if (physnodes[i].end > end) + physnodes[i].end = end; + } + + /* + * Remove all nodes that have no memory or were truncated because of the + * limited address range. + */ + for (i = 0; i < nr_nodes; i++) { + if (physnodes[i].start == physnodes[i].end) + continue; + physnodes[ret].start = physnodes[i].start; + physnodes[ret].end = physnodes[i].end; + ret++; + } + + /* + * If no physical topology was detected, a single node is faked to cover + * the entire address space. + */ + if (!ret) { + physnodes[ret].start = start; + physnodes[ret].end = end; + ret = 1; + } + return ret; +} + /* * Setups up nid to range from addr to addr + size. If the end * boundary is greater than max_addr, then max_addr is used instead. @@ -315,11 +378,9 @@ static char *cmdline __initdata; * allocation past addr and -1 otherwise. addr is adjusted to be at * the end of the node. */ -static int __init setup_node_range(int nid, struct bootnode *nodes, u64 *addr, - u64 size, u64 max_addr) +static int __init setup_node_range(int nid, u64 *addr, u64 size, u64 max_addr) { int ret = 0; - nodes[nid].start = *addr; *addr += size; if (*addr >= max_addr) { @@ -334,13 +395,112 @@ static int __init setup_node_range(int nid, struct bootnode *nodes, u64 *addr, return ret; } +/* + * Sets up nr_nodes fake nodes interleaved over physical nodes ranging from addr + * to max_addr. The return value is the number of nodes allocated. + */ +static int __init split_nodes_interleave(u64 addr, u64 max_addr, + int nr_phys_nodes, int nr_nodes) +{ + nodemask_t physnode_mask = NODE_MASK_NONE; + u64 size; + int big; + int ret = 0; + int i; + + if (nr_nodes <= 0) + return -1; + if (nr_nodes > MAX_NUMNODES) { + pr_info("numa=fake=%d too large, reducing to %d\n", + nr_nodes, MAX_NUMNODES); + nr_nodes = MAX_NUMNODES; + } + + size = (max_addr - addr - e820_hole_size(addr, max_addr)) / nr_nodes; + /* + * Calculate the number of big nodes that can be allocated as a result + * of consolidating the remainder. + */ + big = ((size & ~FAKE_NODE_MIN_HASH_MASK) & nr_nodes) / + FAKE_NODE_MIN_SIZE; + + size &= FAKE_NODE_MIN_HASH_MASK; + if (!size) { + pr_err("Not enough memory for each node. " + "NUMA emulation disabled.\n"); + return -1; + } + + for (i = 0; i < nr_phys_nodes; i++) + if (physnodes[i].start != physnodes[i].end) + node_set(i, physnode_mask); + + /* + * Continue to fill physical nodes with fake nodes until there is no + * memory left on any of them. + */ + while (nodes_weight(physnode_mask)) { + for_each_node_mask(i, physnode_mask) { + u64 end = physnodes[i].start + size; + u64 dma32_end = PFN_PHYS(MAX_DMA32_PFN); + + if (ret < big) + end += FAKE_NODE_MIN_SIZE; + + /* + * Continue to add memory to this fake node if its + * non-reserved memory is less than the per-node size. + */ + while (end - physnodes[i].start - + e820_hole_size(physnodes[i].start, end) < size) { + end += FAKE_NODE_MIN_SIZE; + if (end > physnodes[i].end) { + end = physnodes[i].end; + break; + } + } + + /* + * If there won't be at least FAKE_NODE_MIN_SIZE of + * non-reserved memory in ZONE_DMA32 for the next node, + * this one must extend to the boundary. + */ + if (end < dma32_end && dma32_end - end - + e820_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE) + end = dma32_end; + + /* + * If there won't be enough non-reserved memory for the + * next node, this one must extend to the end of the + * physical node. + */ + if (physnodes[i].end - end - + e820_hole_size(end, physnodes[i].end) < size) + end = physnodes[i].end; + + /* + * Avoid allocating more nodes than requested, which can + * happen as a result of rounding down each node's size + * to FAKE_NODE_MIN_SIZE. + */ + if (nodes_weight(physnode_mask) + ret >= nr_nodes) + end = physnodes[i].end; + + if (setup_node_range(ret++, &physnodes[i].start, + end - physnodes[i].start, + physnodes[i].end) < 0) + node_clear(i, physnode_mask); + } + } + return ret; +} + /* * Splits num_nodes nodes up equally starting at node_start. The return value * is the number of nodes split up and addr is adjusted to be at the end of the * last node allocated. */ -static int __init split_nodes_equally(struct bootnode *nodes, u64 *addr, - u64 max_addr, int node_start, +static int __init split_nodes_equally(u64 *addr, u64 max_addr, int node_start, int num_nodes) { unsigned int big; @@ -388,7 +548,7 @@ static int __init split_nodes_equally(struct bootnode *nodes, u64 *addr, break; } } - if (setup_node_range(i, nodes, addr, end - *addr, max_addr) < 0) + if (setup_node_range(i, addr, end - *addr, max_addr) < 0) break; } return i - node_start + 1; @@ -399,12 +559,12 @@ static int __init split_nodes_equally(struct bootnode *nodes, u64 *addr, * always assigned to a final node and can be asymmetric. Returns the number of * nodes split. */ -static int __init split_nodes_by_size(struct bootnode *nodes, u64 *addr, - u64 max_addr, int node_start, u64 size) +static int __init split_nodes_by_size(u64 *addr, u64 max_addr, int node_start, + u64 size) { int i = node_start; size = (size << 20) & FAKE_NODE_MIN_HASH_MASK; - while (!setup_node_range(i++, nodes, addr, size, max_addr)) + while (!setup_node_range(i++, addr, size, max_addr)) ; return i - node_start; } @@ -413,15 +573,15 @@ static int __init split_nodes_by_size(struct bootnode *nodes, u64 *addr, * Sets up the system RAM area from start_pfn to last_pfn according to the * numa=fake command-line option. */ -static struct bootnode nodes[MAX_NUMNODES] __initdata; - -static int __init numa_emulation(unsigned long start_pfn, unsigned long last_pfn) +static int __init numa_emulation(unsigned long start_pfn, + unsigned long last_pfn, int acpi, int k8) { u64 size, addr = start_pfn << PAGE_SHIFT; u64 max_addr = last_pfn << PAGE_SHIFT; int num_nodes = 0, num = 0, coeff_flag, coeff = -1, i; + int num_phys_nodes; - memset(&nodes, 0, sizeof(nodes)); + num_phys_nodes = setup_physnodes(addr, max_addr, acpi, k8); /* * If the numa=fake command-line is just a single number N, split the * system RAM into N fake nodes. @@ -429,7 +589,8 @@ static int __init numa_emulation(unsigned long start_pfn, unsigned long last_pfn if (!strchr(cmdline, '*') && !strchr(cmdline, ',')) { long n = simple_strtol(cmdline, NULL, 0); - num_nodes = split_nodes_equally(nodes, &addr, max_addr, 0, n); + num_nodes = split_nodes_interleave(addr, max_addr, + num_phys_nodes, n); if (num_nodes < 0) return num_nodes; goto out; @@ -456,8 +617,8 @@ static int __init numa_emulation(unsigned long start_pfn, unsigned long last_pfn size = ((u64)num << 20) & FAKE_NODE_MIN_HASH_MASK; if (size) for (i = 0; i < coeff; i++, num_nodes++) - if (setup_node_range(num_nodes, nodes, - &addr, size, max_addr) < 0) + if (setup_node_range(num_nodes, &addr, + size, max_addr) < 0) goto done; if (!*cmdline) break; @@ -473,7 +634,7 @@ done: if (addr < max_addr) { if (coeff_flag && coeff < 0) { /* Split remaining nodes into num-sized chunks */ - num_nodes += split_nodes_by_size(nodes, &addr, max_addr, + num_nodes += split_nodes_by_size(&addr, max_addr, num_nodes, num); goto out; } @@ -482,7 +643,7 @@ done: /* Split remaining nodes into coeff chunks */ if (coeff <= 0) break; - num_nodes += split_nodes_equally(nodes, &addr, max_addr, + num_nodes += split_nodes_equally(&addr, max_addr, num_nodes, coeff); break; case ',': @@ -490,8 +651,8 @@ done: break; default: /* Give one final node */ - setup_node_range(num_nodes, nodes, &addr, - max_addr - addr, max_addr); + setup_node_range(num_nodes, &addr, max_addr - addr, + max_addr); num_nodes++; } } @@ -505,14 +666,10 @@ out: } /* - * We need to vacate all active ranges that may have been registered by - * SRAT and set acpi_numa to -1 so that srat_disabled() always returns - * true. NUMA emulation has succeeded so we will not scan ACPI nodes. + * We need to vacate all active ranges that may have been registered for + * the e820 memory map. */ remove_all_active_ranges(); -#ifdef CONFIG_ACPI_NUMA - acpi_numa = -1; -#endif for_each_node_mask(i, node_possible_map) { e820_register_active_regions(i, nodes[i].start >> PAGE_SHIFT, nodes[i].end >> PAGE_SHIFT); @@ -533,7 +690,7 @@ void __init initmem_init(unsigned long start_pfn, unsigned long last_pfn, nodes_clear(node_online_map); #ifdef CONFIG_NUMA_EMU - if (cmdline && !numa_emulation(start_pfn, last_pfn)) + if (cmdline && !numa_emulation(start_pfn, last_pfn, acpi, k8)) return; nodes_clear(node_possible_map); nodes_clear(node_online_map); diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c index 891cbe65b2d5..34aa438d60b6 100644 --- a/arch/x86/mm/srat_64.c +++ b/arch/x86/mm/srat_64.c @@ -468,7 +468,6 @@ void __init acpi_fake_nodes(const struct bootnode *fake_nodes, int num_nodes) for (i = 0; i < num_nodes; i++) if (fake_nodes[i].start != fake_nodes[i].end) node_set(i, nodes_parsed); - WARN_ON(!nodes_cover_memory(fake_nodes)); } static int null_slit_node_compare(int a, int b) -- cgit v1.2.3 From 021428ad1418cf3c386a1a0157140c3ea29b17ef Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 21 Nov 2009 00:23:37 -0800 Subject: x86, numa, bootmem: Only free bootmem on NUMA failure path In the NUMA bootmem setup failure path we freed nodedata_phys incorrectly. Signed-off-by: Yinghai Lu Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Rusty Russell Cc: David Rientjes Cc: Andrew Morton LKML-Reference: <4B07A739.3030104@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/mm/numa_64.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/x86/mm/numa_64.c') diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index 086f98a66d80..3acd870d316a 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -239,8 +239,14 @@ setup_node_bootmem(int nodeid, unsigned long start, unsigned long end) bootmap = early_node_mem(nodeid, bootmap_start, end, bootmap_pages<= end) - free_bootmem(nodedata_phys, pgdat_size); + if (nodedata_phys < start || nodedata_phys >= end) { + /* + * only need to free it if it is from other node + * bootmem + */ + if (nid != nodeid) + free_bootmem(nodedata_phys, pgdat_size); + } node_data[nodeid] = NULL; return; } -- cgit v1.2.3 From d9c2d5ac6af87b4491bff107113aaf16f6c2b2d9 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 21 Nov 2009 00:23:37 -0800 Subject: x86, numa: Use near(er) online node instead of roundrobin for NUMA CPU to node mapping is set via the following sequence: 1. numa_init_array(): Set up roundrobin from cpu to online node 2. init_cpu_to_node(): Set that according to apicid_to_node[] according to srat only handle the node that is online, and leave other cpu on node without ram (aka not online) to still roundrobin. 3. later call srat_detect_node for Intel/AMD, will use first_online node or nearby node. Problem is that setup_per_cpu_areas() is not called between 2 and 3, the per_cpu for cpu on node with ram is on different node, and could put that on node with two hops away. So try to optimize this and add find_near_online_node() and call init_cpu_to_node(). Signed-off-by: Yinghai Lu Cc: Tejun Heo Cc: Linus Torvalds Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Rusty Russell Cc: David Rientjes Cc: Andrew Morton LKML-Reference: <4B07A739.3030104@kernel.org> Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 6 +++++- arch/x86/mm/numa_64.c | 21 ++++++++++++++++++++- 2 files changed, 25 insertions(+), 2 deletions(-) (limited to 'arch/x86/mm/numa_64.c') diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 40e1835b35e8..c900b73f9224 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -263,8 +263,12 @@ static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c) /* Don't do the funky fallback heuristics the AMD version employs for now. */ node = apicid_to_node[apicid]; - if (node == NUMA_NO_NODE || !node_online(node)) + if (node == NUMA_NO_NODE) node = first_node(node_online_map); + else if (!node_online(node)) { + /* reuse the value from init_cpu_to_node() */ + node = cpu_to_node(cpu); + } numa_set_node(cpu, node); printk(KERN_INFO "CPU %d/0x%x -> Node %d\n", cpu, apicid, node); diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index 3acd870d316a..83bbc70d11bb 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -764,6 +764,25 @@ static __init int numa_setup(char *opt) early_param("numa", numa_setup); #ifdef CONFIG_NUMA + +static __init int find_near_online_node(int node) +{ + int n, val; + int min_val = INT_MAX; + int best_node = -1; + + for_each_online_node(n) { + val = node_distance(node, n); + + if (val < min_val) { + min_val = val; + best_node = n; + } + } + + return best_node; +} + /* * Setup early cpu_to_node. * @@ -795,7 +814,7 @@ void __init init_cpu_to_node(void) if (node == NUMA_NO_NODE) continue; if (!node_online(node)) - continue; + node = find_near_online_node(node); numa_set_node(cpu, node); } } -- cgit v1.2.3