From 5c3f5892a2db6757a72ce8b27cba90db06683e1d Mon Sep 17 00:00:00 2001 From: Balbir Singh Date: Sat, 8 Dec 2007 09:37:14 +1100 Subject: [PATCH] [POWERPC] Fake NUMA emulation for PowerPC Here's a dumb simple implementation of fake NUMA nodes for PowerPC. Fake NUMA nodes can be specified using the following command line option numa=fake= node range is of the format ,,... Each of the rangeX parameters is passed using memparse(). I find this useful for fake NUMA emulation on my simple PowerPC machine. I've tested it on a non-numa box with the following arguments: numa=fake=1G numa=fake=1G,2G name=fake=1G,512M,2G numa=fake=1500M,2800M mem=3500M numa=fake=1G mem=512M numa=fake=1G mem=1G Signed-off-by: Balbir Singh Acked-by: Olof Johansson Signed-off-by: Paul Mackerras --- arch/powerpc/mm/numa.c | 59 ++++++++++++++++++++++++++++++++++++++---- 1 file changed, 54 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index c12adc3ddffd..1666e7d54cca 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -24,6 +24,8 @@ static int numa_enabled = 1; +static char *cmdline __initdata; + static int numa_debug; #define dbg(args...) if (numa_debug) { printk(KERN_INFO args); } @@ -39,6 +41,43 @@ static bootmem_data_t __initdata plat_node_bdata[MAX_NUMNODES]; static int min_common_depth; static int n_mem_addr_cells, n_mem_size_cells; +static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn, + unsigned int *nid) +{ + unsigned long long mem; + char *p = cmdline; + static unsigned int fake_nid = 0; + static unsigned long long curr_boundary = 0; + + *nid = fake_nid; + if (!p) + return 0; + + mem = memparse(p, &p); + if (!mem) + return 0; + + if (mem < curr_boundary) + return 0; + + curr_boundary = mem; + + if ((end_pfn << PAGE_SHIFT) > mem) { + /* + * Skip commas and spaces + */ + while (*p == ',' || *p == ' ' || *p == '\t') + p++; + + cmdline = p; + fake_nid++; + *nid = fake_nid; + dbg("created new fake_node with id %d\n", fake_nid); + return 1; + } + return 0; +} + static void __cpuinit map_cpu_to_node(int cpu, int node) { numa_cpu_lookup_table[cpu] = node; @@ -344,12 +383,14 @@ static void __init parse_drconf_memory(struct device_node *memory) if (nid == 0xffff || nid >= MAX_NUMNODES) nid = default_nid; } - node_set_online(nid); size = numa_enforce_memory_limit(start, lmb_size); if (!size) continue; + fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid); + node_set_online(nid); + add_active_range(nid, start >> PAGE_SHIFT, (start >> PAGE_SHIFT) + (size >> PAGE_SHIFT)); } @@ -429,7 +470,6 @@ new_range: nid = of_node_to_nid_single(memory); if (nid < 0) nid = default_nid; - node_set_online(nid); if (!(size = numa_enforce_memory_limit(start, size))) { if (--ranges) @@ -438,6 +478,9 @@ new_range: continue; } + fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid); + node_set_online(nid); + add_active_range(nid, start >> PAGE_SHIFT, (start >> PAGE_SHIFT) + (size >> PAGE_SHIFT)); @@ -461,7 +504,7 @@ static void __init setup_nonnuma(void) unsigned long top_of_ram = lmb_end_of_DRAM(); unsigned long total_ram = lmb_phys_mem_size(); unsigned long start_pfn, end_pfn; - unsigned int i; + unsigned int i, nid = 0; printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n", top_of_ram, total_ram); @@ -471,9 +514,11 @@ static void __init setup_nonnuma(void) for (i = 0; i < lmb.memory.cnt; ++i) { start_pfn = lmb.memory.region[i].base >> PAGE_SHIFT; end_pfn = start_pfn + lmb_size_pages(&lmb.memory, i); - add_active_range(0, start_pfn, end_pfn); + + fake_numa_create_new_node(end_pfn, &nid); + add_active_range(nid, start_pfn, end_pfn); + node_set_online(nid); } - node_set_online(0); } void __init dump_numa_cpu_topology(void) @@ -702,6 +747,10 @@ static int __init early_numa(char *p) if (strstr(p, "debug")) numa_debug = 1; + p = strstr(p, "fake="); + if (p) + cmdline = p + strlen("fake="); + return 0; } early_param("numa", early_numa); -- 2.20.1