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Violators will be prosecuted for from ; Tue, 24 Jun 2014 13:40:45 -0400 Received: from b01cxnp22033.gho.pok.ibm.com (b01cxnp22033.gho.pok.ibm.com [9.57.198.23]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id A8B46C90041 for ; Tue, 24 Jun 2014 13:40:37 -0400 (EDT) Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by b01cxnp22033.gho.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s5OHeh2E50856106 for ; Tue, 24 Jun 2014 17:40:43 GMT Received: from d01av02.pok.ibm.com (localhost [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s5OHehX4003982 for ; Tue, 24 Jun 2014 13:40:43 -0400 Date: Tue, 24 Jun 2014 10:40:38 -0700 From: Nishanth Aravamudan Message-ID: <20140624174038.GK4323@linux.vnet.ibm.com> References: <20140623193310.GD4323@linux.vnet.ibm.com> <20140624004825.GE4323@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140624004825.GE4323@linux.vnet.ibm.com> Subject: [Qemu-devel] [RFC PATCH v3] numa: enable sparse node numbering List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: Eduardo Habkost , Alexey Kardashevskiy , Hu Tao , qemu-devel@nongnu.org, Anton Blanchard , David Rientjes , Igor Mammedov Sparse node numbering occurs on powerpc in practice under PowerVM. In order to emulate the same NUMA topology under qemu, the assumption that NUMA nodes are linearly ordered has to be removed. qemu actually already supports (inasmuch as it doesn't throw an error) sparse node numbering by the end-user, but the information is effectively ignored and the nodes are populated linearly starting at 0. This means a user's node ID requests are not honored in the Linux kernel, and that the topology may not be as requested (in terms of the CPU/memory placement). Add a present field to NodeInfo which indicates if a given nodeid was present on the command-line or not. Current code relies on a memory value being passed for a node to indicate presence, which is insufficient in the presence of memoryless nodes or sparse numbering. Adjust the iteration of various NUMA loops to use the maximum known NUMA ID rather than the number of NUMA nodes. numa.c::set_numa_nodes() has become a bit more convoluted for round-robin'ing the CPUs over known nodes when not specified by the user. Note that architecture-specific code still possibly needs changes (forthcoming) for both sparse node numbering and memoryless nodes. This only puts in the generic infrastructure to support that. Examples: (1) qemu-system-x86_64 -enable-kvm -m 4096 -numa node,nodeid=3 -numa node,nodeid=2 -smp 16 Before: node 0 cpus: 0 2 4 6 8 10 12 14 node 0 size: 2048 MB node 1 cpus: 1 3 5 7 9 11 13 15 node 1 size: 2048 MB After: node 2 cpus: 0 2 4 6 8 10 12 14 | node 2 size: 2048 MB | node 3 cpus: 1 3 5 7 9 11 13 15 | node 3 size: 2048 MB (2) qemu-system-x86_64 -enable-kvm -m 4096 -numa node,nodeid=0 -numa node,nodeid=1 -numa node,nodeid=2 -numa node,nodeid=3 -smp 16 node 0 cpus: 0 4 8 12 | node 0 size: 1024 MB | node 1 cpus: 1 5 9 13 | node 1 size: 1024 MB | node 2 cpus: 2 6 10 14 | node 2 size: 1024 MB | node 3 cpus: 3 7 11 15 | node 3 size: 1024 MB (qemu) info numa 4 nodes node 0 cpus: 0 4 8 12 node 0 size: 1024 MB node 1 cpus: 1 5 9 13 node 1 size: 1024 MB node 2 cpus: 2 6 10 14 node 2 size: 1024 MB node 3 cpus: 3 7 11 15 node 3 size: 1024 MB Signed-off-by: Nishanth Aravamudan Tested-by: Hu Tao --- Based off mst's for_upstream tag, which has the NodeInfo changes. v1 -> v2: Modify set_numa_nodes loop for round-robin'ing CPUs. v2 -> v3: Updated changelog to indicate problem being solved. Updated memory_region_allocate_system_memory based upon feedback from Hu. Updated set_numa_nodes loop again to be simpler based upon feedback from Hu. Fixed bug with a mix of nodes with nodeid specified and without, where the same nodeid would be used by the explicit specification and the auto-numbering code. diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index 277230d..b90bf66 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -145,11 +145,13 @@ extern int mem_prealloc; */ #define MAX_CPUMASK_BITS 255 -extern int nb_numa_nodes; +extern int nb_numa_nodes; /* Number of NUMA nodes */ +extern int max_numa_node; /* Highest specified NUMA node ID */ typedef struct node_info { uint64_t node_mem; DECLARE_BITMAP(node_cpu, MAX_CPUMASK_BITS); struct HostMemoryBackend *node_memdev; + bool present; } NodeInfo; extern NodeInfo numa_info[MAX_NODES]; void set_numa_nodes(void); diff --git a/monitor.c b/monitor.c index c7f8797..4721996 100644 --- a/monitor.c +++ b/monitor.c @@ -2003,7 +2003,10 @@ static void do_info_numa(Monitor *mon, const QDict *qdict) CPUState *cpu; monitor_printf(mon, "%d nodes\n", nb_numa_nodes); - for (i = 0; i < nb_numa_nodes; i++) { + for (i = 0; i < max_numa_node; i++) { + if (!numa_info[i].present) { + continue; + } monitor_printf(mon, "node %d cpus:", i); CPU_FOREACH(cpu) { if (cpu->numa_node == i) { diff --git a/numa.c b/numa.c index e471afe..d6b86ab 100644 --- a/numa.c +++ b/numa.c @@ -53,7 +53,10 @@ static void numa_node_parse(NumaNodeOptions *node, QemuOpts *opts, Error **errp) if (node->has_nodeid) { nodenr = node->nodeid; } else { - nodenr = nb_numa_nodes; + nodenr = 0; + while (numa_info[nodenr].present) { + nodenr++; + } } if (nodenr >= MAX_NODES) { @@ -106,6 +109,10 @@ static void numa_node_parse(NumaNodeOptions *node, QemuOpts *opts, Error **errp) numa_info[nodenr].node_mem = object_property_get_int(o, "size", NULL); numa_info[nodenr].node_memdev = MEMORY_BACKEND(o); } + numa_info[nodenr].present = true; + if (nodenr >= max_numa_node) { + max_numa_node = nodenr + 1; + } } int numa_init_func(QemuOpts *opts, void *opaque) @@ -155,7 +162,7 @@ void set_numa_nodes(void) { if (nb_numa_nodes > 0) { uint64_t numa_total; - int i; + int i, j = -1; if (nb_numa_nodes > MAX_NODES) { nb_numa_nodes = MAX_NODES; @@ -164,27 +171,29 @@ void set_numa_nodes(void) /* If no memory size if given for any node, assume the default case * and distribute the available memory equally across all nodes */ - for (i = 0; i < nb_numa_nodes; i++) { - if (numa_info[i].node_mem != 0) { + for (i = 0; i < max_numa_node; i++) { + if (numa_info[i].present && numa_info[i].node_mem != 0) { break; } } - if (i == nb_numa_nodes) { + if (i == max_numa_node) { uint64_t usedmem = 0; /* On Linux, the each node's border has to be 8MB aligned, * the final node gets the rest. */ - for (i = 0; i < nb_numa_nodes - 1; i++) { - numa_info[i].node_mem = (ram_size / nb_numa_nodes) & - ~((1 << 23UL) - 1); - usedmem += numa_info[i].node_mem; + for (i = 0; i < max_numa_node - 1; i++) { + if (numa_info[i].present) { + numa_info[i].node_mem = (ram_size / nb_numa_nodes) & + ~((1 << 23UL) - 1); + usedmem += numa_info[i].node_mem; + } } numa_info[i].node_mem = ram_size - usedmem; } numa_total = 0; - for (i = 0; i < nb_numa_nodes; i++) { + for (i = 0; i < max_numa_node; i++) { numa_total += numa_info[i].node_mem; } if (numa_total != ram_size) { @@ -194,8 +203,9 @@ void set_numa_nodes(void) exit(1); } - for (i = 0; i < nb_numa_nodes; i++) { - if (!bitmap_empty(numa_info[i].node_cpu, MAX_CPUMASK_BITS)) { + for (i = 0; i < max_numa_node; i++) { + if (numa_info[i].present && + !bitmap_empty(numa_info[i].node_cpu, MAX_CPUMASK_BITS)) { break; } } @@ -203,9 +213,12 @@ void set_numa_nodes(void) * must cope with this anyway, because there are BIOSes out there in * real machines which also use this scheme. */ - if (i == nb_numa_nodes) { + if (i == max_numa_node) { for (i = 0; i < max_cpus; i++) { - set_bit(i, numa_info[i % nb_numa_nodes].node_cpu); + do { + j = (j + 1) % max_numa_node; + } while (!numa_info[j].present); + set_bit(i, numa_info[j].node_cpu); } } } @@ -217,8 +230,9 @@ void set_numa_modes(void) int i; CPU_FOREACH(cpu) { - for (i = 0; i < nb_numa_nodes; i++) { - if (test_bit(cpu->cpu_index, numa_info[i].node_cpu)) { + for (i = 0; i < max_numa_node; i++) { + if (numa_info[i].present && + test_bit(cpu->cpu_index, numa_info[i].node_cpu)) { cpu->numa_node = i; } } @@ -266,10 +280,13 @@ void memory_region_allocate_system_memory(MemoryRegion *mr, Object *owner, } memory_region_init(mr, owner, name, ram_size); - for (i = 0; i < MAX_NODES; i++) { + for (i = 0; i < max_numa_node; i++) { Error *local_err = NULL; uint64_t size = numa_info[i].node_mem; HostMemoryBackend *backend = numa_info[i].node_memdev; + if (!numa_info[i].present) { + continue; + } if (!backend) { continue; } diff --git a/vl.c b/vl.c index 54b4627..e1a6ab8 100644 --- a/vl.c +++ b/vl.c @@ -195,6 +195,7 @@ static QTAILQ_HEAD(, FWBootEntry) fw_boot_order = QTAILQ_HEAD_INITIALIZER(fw_boot_order); int nb_numa_nodes; +int max_numa_node; NodeInfo numa_info[MAX_NODES]; uint8_t qemu_uuid[16]; @@ -2967,10 +2968,12 @@ int main(int argc, char **argv, char **envp) for (i = 0; i < MAX_NODES; i++) { numa_info[i].node_mem = 0; + numa_info[i].present = false; bitmap_zero(numa_info[i].node_cpu, MAX_CPUMASK_BITS); } nb_numa_nodes = 0; + max_numa_node = -1; nb_nics = 0; bdrv_init_with_whitelist();