From 5f5d8405d1c50f5cf7e1dbfe9c9b44e2f015c8fd Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 24 Feb 2009 11:57:21 +0900 Subject: [PATCH] x86: separate out setup_pcpu_4k() from setup_per_cpu_areas() Impact: modularize percpu first chunk allocation x86 is gonna have a few different strategies for the first chunk allocation. Modularize it by separating out the current allocation mechanism into pcpu_alloc_bootmem() and setup_pcpu_4k(). Signed-off-by: Tejun Heo --- arch/x86/kernel/setup_percpu.c | 144 +++++++++++++++++++++++---------- 1 file changed, 102 insertions(+), 42 deletions(-) diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index d928e8887201..4a17c96f4f6c 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -41,6 +42,52 @@ unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { }; EXPORT_SYMBOL(__per_cpu_offset); +/** + * pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu + * @cpu: cpu to allocate for + * @size: size allocation in bytes + * @align: alignment + * + * Allocate @size bytes aligned at @align for cpu @cpu. This wrapper + * does the right thing for NUMA regardless of the current + * configuration. + * + * RETURNS: + * Pointer to the allocated area on success, NULL on failure. + */ +static void * __init pcpu_alloc_bootmem(unsigned int cpu, unsigned long size, + unsigned long align) +{ + const unsigned long goal = __pa(MAX_DMA_ADDRESS); +#ifdef CONFIG_NEED_MULTIPLE_NODES + int node = early_cpu_to_node(cpu); + void *ptr; + + if (!node_online(node) || !NODE_DATA(node)) { + ptr = __alloc_bootmem_nopanic(size, align, goal); + pr_info("cpu %d has no node %d or node-local memory\n", + cpu, node); + pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n", + cpu, size, __pa(ptr)); + } else { + ptr = __alloc_bootmem_node_nopanic(NODE_DATA(node), + size, align, goal); + pr_debug("per cpu data for cpu%d %lu bytes on node%d at " + "%016lx\n", cpu, size, node, __pa(ptr)); + } + return ptr; +#else + return __alloc_bootmem_nopanic(size, align, goal); +#endif +} + +/* + * 4k page allocator + * + * This is the basic allocator. Static percpu area is allocated + * page-by-page and most of initialization is done by the generic + * setup function. + */ static struct page **pcpu4k_pages __initdata; static int pcpu4k_nr_static_pages __initdata; @@ -56,6 +103,51 @@ static void __init pcpu4k_populate_pte(unsigned long addr) populate_extra_pte(addr); } +static ssize_t __init setup_pcpu_4k(size_t static_size) +{ + size_t pages_size; + unsigned int cpu; + int i, j; + ssize_t ret; + + pcpu4k_nr_static_pages = PFN_UP(static_size); + + /* unaligned allocations can't be freed, round up to page size */ + pages_size = PFN_ALIGN(pcpu4k_nr_static_pages * num_possible_cpus() + * sizeof(pcpu4k_pages[0])); + pcpu4k_pages = alloc_bootmem(pages_size); + + /* allocate and copy */ + j = 0; + for_each_possible_cpu(cpu) + for (i = 0; i < pcpu4k_nr_static_pages; i++) { + void *ptr; + + ptr = pcpu_alloc_bootmem(cpu, PAGE_SIZE, PAGE_SIZE); + if (!ptr) + goto enomem; + + memcpy(ptr, __per_cpu_load + i * PAGE_SIZE, PAGE_SIZE); + pcpu4k_pages[j++] = virt_to_page(ptr); + } + + /* we're ready, commit */ + pr_info("PERCPU: Allocated %d 4k pages, static data %zu bytes\n", + pcpu4k_nr_static_pages, static_size); + + ret = pcpu_setup_first_chunk(pcpu4k_get_page, static_size, 0, 0, NULL, + pcpu4k_populate_pte); + goto out_free_ar; + +enomem: + while (--j >= 0) + free_bootmem(__pa(page_address(pcpu4k_pages[j])), PAGE_SIZE); + ret = -ENOMEM; +out_free_ar: + free_bootmem(__pa(pcpu4k_pages), pages_size); + return ret; +} + static inline void setup_percpu_segment(int cpu) { #ifdef CONFIG_X86_32 @@ -76,56 +168,24 @@ static inline void setup_percpu_segment(int cpu) */ void __init setup_per_cpu_areas(void) { - ssize_t size = __per_cpu_end - __per_cpu_start; - unsigned int nr_cpu_pages = DIV_ROUND_UP(size, PAGE_SIZE); - static struct page **pages; - size_t pages_size; - unsigned int cpu, i, j; + size_t static_size = __per_cpu_end - __per_cpu_start; + unsigned int cpu; unsigned long delta; size_t pcpu_unit_size; + ssize_t ret; pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n", NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids); - pr_info("PERCPU: Allocating %zd bytes for static per cpu data\n", size); - - pages_size = nr_cpu_pages * num_possible_cpus() * sizeof(pages[0]); - pages = alloc_bootmem(pages_size); - - j = 0; - for_each_possible_cpu(cpu) { - void *ptr; - - for (i = 0; i < nr_cpu_pages; i++) { -#ifndef CONFIG_NEED_MULTIPLE_NODES - ptr = alloc_bootmem_pages(PAGE_SIZE); -#else - int node = early_cpu_to_node(cpu); - - if (!node_online(node) || !NODE_DATA(node)) { - ptr = alloc_bootmem_pages(PAGE_SIZE); - pr_info("cpu %d has no node %d or node-local " - "memory\n", cpu, node); - pr_debug("per cpu data for cpu%d at %016lx\n", - cpu, __pa(ptr)); - } else { - ptr = alloc_bootmem_pages_node(NODE_DATA(node), - PAGE_SIZE); - pr_debug("per cpu data for cpu%d on node%d " - "at %016lx\n", cpu, node, __pa(ptr)); - } -#endif - memcpy(ptr, __per_cpu_load + i * PAGE_SIZE, PAGE_SIZE); - pages[j++] = virt_to_page(ptr); - } - } - pcpu4k_pages = pages; - pcpu4k_nr_static_pages = nr_cpu_pages; - pcpu_unit_size = pcpu_setup_first_chunk(pcpu4k_get_page, size, 0, 0, - NULL, pcpu4k_populate_pte); + /* allocate percpu area */ + ret = setup_pcpu_4k(static_size); + if (ret < 0) + panic("cannot allocate static percpu area (%zu bytes, err=%zd)", + static_size, ret); - free_bootmem(__pa(pages), pages_size); + pcpu_unit_size = ret; + /* alrighty, percpu areas up and running */ delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; for_each_possible_cpu(cpu) { per_cpu_offset(cpu) = delta + cpu * pcpu_unit_size; -- 2.34.1