diff options
Diffstat (limited to 'arch/x86/kernel/setup_percpu.c')
-rw-r--r-- | arch/x86/kernel/setup_percpu.c | 155 |
1 files changed, 28 insertions, 127 deletions
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 67f6314de9f1..d559af913e1f 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -55,6 +55,7 @@ EXPORT_SYMBOL(__per_cpu_offset); #define PERCPU_FIRST_CHUNK_RESERVE 0 #endif +#ifdef CONFIG_X86_32 /** * pcpu_need_numa - determine percpu allocation needs to consider NUMA * @@ -83,6 +84,7 @@ static bool __init pcpu_need_numa(void) #endif return false; } +#endif /** * pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu @@ -136,128 +138,23 @@ static void __init pcpu_fc_free(void *ptr, size_t size) free_bootmem(__pa(ptr), size); } -/* - * Large page remapping allocator - */ -#ifdef CONFIG_NEED_MULTIPLE_NODES -static void __init pcpul_map(void *ptr, size_t size, void *addr) -{ - pmd_t *pmd, pmd_v; - - pmd = populate_extra_pmd((unsigned long)addr); - pmd_v = pfn_pmd(page_to_pfn(virt_to_page(ptr)), PAGE_KERNEL_LARGE); - set_pmd(pmd, pmd_v); -} - -static int pcpu_lpage_cpu_distance(unsigned int from, unsigned int to) +static int __init pcpu_cpu_distance(unsigned int from, unsigned int to) { +#ifdef CONFIG_NEED_MULTIPLE_NODES if (early_cpu_to_node(from) == early_cpu_to_node(to)) return LOCAL_DISTANCE; else return REMOTE_DISTANCE; -} - -static int __init setup_pcpu_lpage(bool chosen) -{ - size_t reserve = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE; - size_t dyn_size = reserve - PERCPU_FIRST_CHUNK_RESERVE; - struct pcpu_alloc_info *ai; - int rc; - - /* on non-NUMA, embedding is better */ - if (!chosen && !pcpu_need_numa()) - return -EINVAL; - - /* need PSE */ - if (!cpu_has_pse) { - pr_warning("PERCPU: lpage allocator requires PSE\n"); - return -EINVAL; - } - - /* allocate and build unit_map */ - ai = pcpu_build_alloc_info(PERCPU_FIRST_CHUNK_RESERVE, dyn_size, - PMD_SIZE, pcpu_lpage_cpu_distance); - if (IS_ERR(ai)) { - pr_warning("PERCPU: failed to build unit_map (%ld)\n", - PTR_ERR(ai)); - return PTR_ERR(ai); - } - - /* do the parameters look okay? */ - if (!chosen) { - size_t vm_size = VMALLOC_END - VMALLOC_START; - size_t tot_size = 0; - int group; - - for (group = 0; group < ai->nr_groups; group++) - tot_size += ai->unit_size * ai->groups[group].nr_units; - - /* don't consume more than 20% of vmalloc area */ - if (tot_size > vm_size / 5) { - pr_info("PERCPU: too large chunk size %zuMB for " - "large page remap\n", tot_size >> 20); - rc = -EINVAL; - goto out_free; - } - } - - rc = pcpu_lpage_first_chunk(ai, pcpu_fc_alloc, pcpu_fc_free, pcpul_map); -out_free: - pcpu_free_alloc_info(ai); - return rc; -} #else -static int __init setup_pcpu_lpage(bool chosen) -{ - return -EINVAL; -} + return LOCAL_DISTANCE; #endif - -/* - * Embedding allocator - * - * The first chunk is sized to just contain the static area plus - * module and dynamic reserves and embedded into linear physical - * mapping so that it can use PMD mapping without additional TLB - * pressure. - */ -static int __init setup_pcpu_embed(bool chosen) -{ - size_t reserve = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE; - - /* - * If large page isn't supported, there's no benefit in doing - * this. Also, embedding allocation doesn't play well with - * NUMA. - */ - if (!chosen && (!cpu_has_pse || pcpu_need_numa())) - return -EINVAL; - - return pcpu_embed_first_chunk(PERCPU_FIRST_CHUNK_RESERVE, - reserve - PERCPU_FIRST_CHUNK_RESERVE, - PAGE_SIZE, NULL, pcpu_fc_alloc, - pcpu_fc_free); } -/* - * Page allocator - * - * Boring fallback 4k page allocator. This allocator puts more - * pressure on PTE TLBs but other than that behaves nicely on both UMA - * and NUMA. - */ static void __init pcpup_populate_pte(unsigned long addr) { populate_extra_pte(addr); } -static int __init setup_pcpu_page(void) -{ - return pcpu_page_first_chunk(PERCPU_FIRST_CHUNK_RESERVE, - pcpu_fc_alloc, pcpu_fc_free, - pcpup_populate_pte); -} - static inline void setup_percpu_segment(int cpu) { #ifdef CONFIG_X86_32 @@ -281,30 +178,34 @@ void __init setup_per_cpu_areas(void) NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids); /* - * Allocate percpu area. If PSE is supported, try to make use - * of large page mappings. Please read comments on top of - * each allocator for details. + * Allocate percpu area. Embedding allocator is our favorite; + * however, on NUMA configurations, it can result in very + * sparse unit mapping and vmalloc area isn't spacious enough + * on 32bit. Use page in that case. */ +#ifdef CONFIG_X86_32 + if (pcpu_chosen_fc == PCPU_FC_AUTO && pcpu_need_numa()) + pcpu_chosen_fc = PCPU_FC_PAGE; +#endif rc = -EINVAL; - if (pcpu_chosen_fc != PCPU_FC_AUTO) { - if (pcpu_chosen_fc != PCPU_FC_PAGE) { - if (pcpu_chosen_fc == PCPU_FC_LPAGE) - rc = setup_pcpu_lpage(true); - else - rc = setup_pcpu_embed(true); - - if (rc < 0) - pr_warning("PERCPU: %s allocator failed (%d), " - "falling back to page size\n", - pcpu_fc_names[pcpu_chosen_fc], rc); - } - } else { - rc = setup_pcpu_lpage(false); + if (pcpu_chosen_fc != PCPU_FC_PAGE) { + const size_t atom_size = cpu_has_pse ? PMD_SIZE : PAGE_SIZE; + const size_t dyn_size = PERCPU_MODULE_RESERVE + + PERCPU_DYNAMIC_RESERVE - PERCPU_FIRST_CHUNK_RESERVE; + + rc = pcpu_embed_first_chunk(PERCPU_FIRST_CHUNK_RESERVE, + dyn_size, atom_size, + pcpu_cpu_distance, + pcpu_fc_alloc, pcpu_fc_free); if (rc < 0) - rc = setup_pcpu_embed(false); + pr_warning("PERCPU: %s allocator failed (%d), " + "falling back to page size\n", + pcpu_fc_names[pcpu_chosen_fc], rc); } if (rc < 0) - rc = setup_pcpu_page(); + rc = pcpu_page_first_chunk(PERCPU_FIRST_CHUNK_RESERVE, + pcpu_fc_alloc, pcpu_fc_free, + pcpup_populate_pte); if (rc < 0) panic("cannot initialize percpu area (err=%d)", rc); |