Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753000AbbHQDRK (ORCPT ); Sun, 16 Aug 2015 23:17:10 -0400 Received: from mga11.intel.com ([192.55.52.93]:1356 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752685AbbHQDRF (ORCPT ); Sun, 16 Aug 2015 23:17:05 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.15,692,1432623600"; d="scan'208";a="543143688" From: Jiang Liu To: Andrew Morton , Mel Gorman , David Rientjes , Mike Galbraith , Peter Zijlstra , "Rafael J . Wysocki" , Tang Chen , Tejun Heo , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, "Rafael J. Wysocki" , Len Brown , Pavel Machek , Borislav Petkov , Andy Lutomirski , Boris Ostrovsky , Dave Hansen , =?UTF-8?q?Jan=20H=2E=20Sch=C3=B6nherr?= , Igor Mammedov , "Paul E. McKenney" , Xishi Qiu , Jiang Liu , Luiz Capitulino , Dave Young Cc: Tony Luck , linux-mm@kvack.org, linux-hotplug@vger.kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar , linux-pm@vger.kernel.org Subject: [Patch V3 9/9] mm, x86: Enable memoryless node support to better support CPU/memory hotplug Date: Mon, 17 Aug 2015 11:19:06 +0800 Message-Id: <1439781546-7217-10-git-send-email-jiang.liu@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1439781546-7217-1-git-send-email-jiang.liu@linux.intel.com> References: <1439781546-7217-1-git-send-email-jiang.liu@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8305 Lines: 250 With current implementation, all CPUs within a NUMA node will be assocaited with another NUMA node if the node has no memory installed. For example, on a four-node system, CPUs on node 2 and 3 are associated with node 0 when are no memory install on node 2 and 3, which may confuse users. root@bkd01sdp:~# numactl --hardware available: 2 nodes (0-1) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 node 0 size: 15602 MB node 0 free: 15014 MB node 1 cpus: 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 node 1 size: 15985 MB node 1 free: 15686 MB node distances: node 0 1 0: 10 21 1: 21 10 To be worse, the CPU affinity relationship won't get fixed even after memory has been added to those nodes. After memory hot-addition to node 2, CPUs on node 2 are still associated with node 0. This may cause sub-optimal performance. root@bkd01sdp:/sys/devices/system/node/node2# numactl --hardware available: 3 nodes (0-2) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 node 0 size: 15602 MB node 0 free: 14743 MB node 1 cpus: 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 node 1 size: 15985 MB node 1 free: 15715 MB node 2 cpus: node 2 size: 128 MB node 2 free: 128 MB node distances: node 0 1 2 0: 10 21 21 1: 21 10 21 2: 21 21 10 With support of memoryless node enabled, it will correctly report system hardware topology for nodes without memory installed. root@bkd01sdp:~# numactl --hardware available: 4 nodes (0-3) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 node 0 size: 15725 MB node 0 free: 15129 MB node 1 cpus: 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 node 1 size: 15862 MB node 1 free: 15627 MB node 2 cpus: 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 node 2 size: 0 MB node 2 free: 0 MB node 3 cpus: 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 node 3 size: 0 MB node 3 free: 0 MB node distances: node 0 1 2 3 0: 10 21 21 21 1: 21 10 21 21 2: 21 21 10 21 3: 21 21 21 10 With memoryless node enabled, CPUs are correctly associated with node 2 after memory hot-addition to node 2. root@bkd01sdp:/sys/devices/system/node/node2# numactl --hardware available: 4 nodes (0-3) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 node 0 size: 15725 MB node 0 free: 14872 MB node 1 cpus: 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 node 1 size: 15862 MB node 1 free: 15641 MB node 2 cpus: 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 node 2 size: 128 MB node 2 free: 127 MB node 3 cpus: 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 node 3 size: 0 MB node 3 free: 0 MB node distances: node 0 1 2 3 0: 10 21 21 21 1: 21 10 21 21 2: 21 21 10 21 3: 21 21 21 10 Signed-off-by: Jiang Liu --- arch/x86/Kconfig | 3 +++ arch/x86/kernel/acpi/boot.c | 4 +++- arch/x86/kernel/smpboot.c | 2 ++ arch/x86/mm/numa.c | 49 +++++++++++++++++++++++++++++++------------ 4 files changed, 44 insertions(+), 14 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index b3a1a5d77d92..5d7ad70ace0d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2069,6 +2069,9 @@ config USE_PERCPU_NUMA_NODE_ID def_bool y depends on NUMA +config HAVE_MEMORYLESS_NODES + def_bool NUMA + config ARCH_ENABLE_SPLIT_PMD_PTLOCK def_bool y depends on X86_64 || X86_PAE diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 07930e1d2fe9..3403f1f0f28d 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -711,6 +711,7 @@ static void acpi_map_cpu2node(acpi_handle handle, int cpu, int physid) } set_apicid_to_node(physid, nid); numa_set_node(cpu, nid); + set_cpu_numa_mem(cpu, local_memory_node(nid)); } #endif } @@ -743,9 +744,10 @@ int acpi_unmap_cpu(int cpu) { #ifdef CONFIG_ACPI_NUMA set_apicid_to_node(per_cpu(x86_cpu_to_apicid, cpu), NUMA_NO_NODE); + set_cpu_numa_mem(cpu, NUMA_NO_NODE); #endif - per_cpu(x86_cpu_to_apicid, cpu) = -1; + per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID; set_cpu_present(cpu, false); num_processors--; diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index b1f3ed9c7a9e..aeec91ac6fd4 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -162,6 +162,8 @@ static void smp_callin(void) */ phys_id = read_apic_id(); + set_numa_mem(local_memory_node(cpu_to_node(cpuid))); + /* * the boot CPU has finished the init stage and is spinning * on callin_map until we finish. We are free to set up this diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index 08860bdf5744..f2a4e23bd14d 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -22,6 +22,7 @@ int __initdata numa_off; nodemask_t numa_nodes_parsed __initdata; +static nodemask_t numa_nodes_empty __initdata; struct pglist_data *node_data[MAX_NUMNODES] __read_mostly; EXPORT_SYMBOL(node_data); @@ -560,17 +561,16 @@ static int __init numa_register_memblks(struct numa_meminfo *mi) end = max(mi->blk[i].end, end); } - if (start >= end) - continue; - /* * Don't confuse VM with a node that doesn't have the * minimum amount of memory: */ - if (end && (end - start) < NODE_MIN_SIZE) - continue; - - alloc_node_data(nid); + if (start < end && (end - start) >= NODE_MIN_SIZE) { + alloc_node_data(nid); + } else if (IS_ENABLED(CONFIG_HAVE_MEMORYLESS_NODES)) { + alloc_node_data(nid); + node_set(nid, numa_nodes_empty); + } } /* Dump memblock with node info and return. */ @@ -587,14 +587,18 @@ static int __init numa_register_memblks(struct numa_meminfo *mi) */ static void __init numa_init_array(void) { - int rr, i; + int i, rr = MAX_NUMNODES; - rr = first_node(node_online_map); for (i = 0; i < nr_cpu_ids; i++) { + /* Search for an onlined node with memory */ + do { + if (rr != MAX_NUMNODES) + rr = next_node(rr, node_online_map); + if (rr == MAX_NUMNODES) + rr = first_node(node_online_map); + } while (node_isset(rr, numa_nodes_empty)); + numa_set_node(i, rr); - rr = next_node(rr, node_online_map); - if (rr == MAX_NUMNODES) - rr = first_node(node_online_map); } } @@ -696,9 +700,12 @@ static __init int find_near_online_node(int node) { int n, val; int min_val = INT_MAX; - int best_node = -1; + int best_node = NUMA_NO_NODE; for_each_online_node(n) { + if (node_isset(n, numa_nodes_empty)) + continue; + val = node_distance(node, n); if (val < min_val) { @@ -739,6 +746,22 @@ void __init init_cpu_to_node(void) if (!node_online(node)) node = find_near_online_node(node); numa_set_node(cpu, node); + if (node_spanned_pages(node)) + set_cpu_numa_mem(cpu, node); + if (IS_ENABLED(CONFIG_HAVE_MEMORYLESS_NODES)) + node_clear(node, numa_nodes_empty); + } + + /* Destroy empty nodes */ + if (IS_ENABLED(CONFIG_HAVE_MEMORYLESS_NODES)) { + int nid; + const size_t nd_size = roundup(sizeof(pg_data_t), PAGE_SIZE); + + for_each_node_mask(nid, numa_nodes_empty) { + node_set_offline(nid); + memblock_free(__pa(node_data[nid]), nd_size); + node_data[nid] = NULL; + } } } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/