1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */ 21da177e4SLinus Torvalds #ifndef __LINUX_PERCPU_H 31da177e4SLinus Torvalds #define __LINUX_PERCPU_H 47ff6f082SMartin Peschke 5309381feSSasha Levin #include <linux/mmdebug.h> 60a3021f4SRobert P. J. Day #include <linux/preempt.h> 71da177e4SLinus Torvalds #include <linux/smp.h> 87ff6f082SMartin Peschke #include <linux/cpumask.h> 96a242909STejun Heo #include <linux/pfn.h> 10de380b55STejun Heo #include <linux/init.h> 1154da6a09SPeter Zijlstra #include <linux/cleanup.h> 127ff6f082SMartin Peschke 131da177e4SLinus Torvalds #include <asm/percpu.h> 141da177e4SLinus Torvalds 156a242909STejun Heo /* enough to cover all DEFINE_PER_CPUs in modules */ 16b00742d3SJeremy Fitzhardinge #ifdef CONFIG_MODULES 176a242909STejun Heo #define PERCPU_MODULE_RESERVE (8 << 10) 18b00742d3SJeremy Fitzhardinge #else 19b00742d3SJeremy Fitzhardinge #define PERCPU_MODULE_RESERVE 0 201da177e4SLinus Torvalds #endif 211da177e4SLinus Torvalds 228d408b4bSTejun Heo /* minimum unit size, also is the maximum supported allocation size */ 236abad5acSTejun Heo #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) 248d408b4bSTejun Heo 25d2f3c384SDennis Zhou (Facebook) /* minimum allocation size and shift in bytes */ 26d2f3c384SDennis Zhou (Facebook) #define PCPU_MIN_ALLOC_SHIFT 2 27d2f3c384SDennis Zhou (Facebook) #define PCPU_MIN_ALLOC_SIZE (1 << PCPU_MIN_ALLOC_SHIFT) 28d2f3c384SDennis Zhou (Facebook) 298d408b4bSTejun Heo /* 30b239f7daSDennis Zhou * The PCPU_BITMAP_BLOCK_SIZE must be the same size as PAGE_SIZE as the 31b239f7daSDennis Zhou * updating of hints is used to manage the nr_empty_pop_pages in both 32b239f7daSDennis Zhou * the chunk and globally. 33ca460b3cSDennis Zhou (Facebook) */ 34ca460b3cSDennis Zhou (Facebook) #define PCPU_BITMAP_BLOCK_SIZE PAGE_SIZE 35ca460b3cSDennis Zhou (Facebook) #define PCPU_BITMAP_BLOCK_BITS (PCPU_BITMAP_BLOCK_SIZE >> \ 36ca460b3cSDennis Zhou (Facebook) PCPU_MIN_ALLOC_SHIFT) 37ca460b3cSDennis Zhou (Facebook) 38*3c615294SGONG, Ruiqi #ifdef CONFIG_RANDOM_KMALLOC_CACHES 39*3c615294SGONG, Ruiqi #define PERCPU_DYNAMIC_SIZE_SHIFT 12 40*3c615294SGONG, Ruiqi #else 41*3c615294SGONG, Ruiqi #define PERCPU_DYNAMIC_SIZE_SHIFT 10 42*3c615294SGONG, Ruiqi #endif 43*3c615294SGONG, Ruiqi 44ca460b3cSDennis Zhou (Facebook) /* 45099a19d9STejun Heo * Percpu allocator can serve percpu allocations before slab is 46099a19d9STejun Heo * initialized which allows slab to depend on the percpu allocator. 47d667c949SBaoquan He * The following parameter decide how much resource to preallocate 48d667c949SBaoquan He * for this. Keep PERCPU_DYNAMIC_RESERVE equal to or larger than 49d667c949SBaoquan He * PERCPU_DYNAMIC_EARLY_SIZE. 50099a19d9STejun Heo */ 51*3c615294SGONG, Ruiqi #define PERCPU_DYNAMIC_EARLY_SIZE (20 << PERCPU_DYNAMIC_SIZE_SHIFT) 52099a19d9STejun Heo 53099a19d9STejun Heo /* 548d408b4bSTejun Heo * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy 556b19b0c2STejun Heo * back on the first chunk for dynamic percpu allocation if arch is 566b19b0c2STejun Heo * manually allocating and mapping it for faster access (as a part of 576b19b0c2STejun Heo * large page mapping for example). 588d408b4bSTejun Heo * 596b19b0c2STejun Heo * The following values give between one and two pages of free space 606b19b0c2STejun Heo * after typical minimal boot (2-way SMP, single disk and NIC) with 616b19b0c2STejun Heo * both defconfig and a distro config on x86_64 and 32. More 626b19b0c2STejun Heo * intelligent way to determine this would be nice. 638d408b4bSTejun Heo */ 648d408b4bSTejun Heo #if BITS_PER_LONG > 32 65*3c615294SGONG, Ruiqi #define PERCPU_DYNAMIC_RESERVE (28 << PERCPU_DYNAMIC_SIZE_SHIFT) 668d408b4bSTejun Heo #else 67*3c615294SGONG, Ruiqi #define PERCPU_DYNAMIC_RESERVE (20 << PERCPU_DYNAMIC_SIZE_SHIFT) 688d408b4bSTejun Heo #endif 698d408b4bSTejun Heo 70fbf59bc9STejun Heo extern void *pcpu_base_addr; 71fb435d52STejun Heo extern const unsigned long *pcpu_unit_offsets; 72fbf59bc9STejun Heo 73fd1e8a1fSTejun Heo struct pcpu_group_info { 74fd1e8a1fSTejun Heo int nr_units; /* aligned # of units */ 75fd1e8a1fSTejun Heo unsigned long base_offset; /* base address offset */ 76fd1e8a1fSTejun Heo unsigned int *cpu_map; /* unit->cpu map, empty 77fd1e8a1fSTejun Heo * entries contain NR_CPUS */ 78fd1e8a1fSTejun Heo }; 79fd1e8a1fSTejun Heo 80fd1e8a1fSTejun Heo struct pcpu_alloc_info { 81fd1e8a1fSTejun Heo size_t static_size; 82fd1e8a1fSTejun Heo size_t reserved_size; 83fd1e8a1fSTejun Heo size_t dyn_size; 84fd1e8a1fSTejun Heo size_t unit_size; 85fd1e8a1fSTejun Heo size_t atom_size; 86fd1e8a1fSTejun Heo size_t alloc_size; 87fd1e8a1fSTejun Heo size_t __ai_size; /* internal, don't use */ 88fd1e8a1fSTejun Heo int nr_groups; /* 0 if grouping unnecessary */ 89fd1e8a1fSTejun Heo struct pcpu_group_info groups[]; 90fd1e8a1fSTejun Heo }; 91fd1e8a1fSTejun Heo 92f58dc01bSTejun Heo enum pcpu_fc { 93f58dc01bSTejun Heo PCPU_FC_AUTO, 94f58dc01bSTejun Heo PCPU_FC_EMBED, 95f58dc01bSTejun Heo PCPU_FC_PAGE, 96f58dc01bSTejun Heo 97f58dc01bSTejun Heo PCPU_FC_NR, 98f58dc01bSTejun Heo }; 9917f3609cSAndi Kleen extern const char * const pcpu_fc_names[PCPU_FC_NR]; 100f58dc01bSTejun Heo 101f58dc01bSTejun Heo extern enum pcpu_fc pcpu_chosen_fc; 102f58dc01bSTejun Heo 1031ca3fb3aSKefeng Wang typedef int (pcpu_fc_cpu_to_node_fn_t)(int cpu); 104a530b795STejun Heo typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to); 105fbf59bc9STejun Heo 106fd1e8a1fSTejun Heo extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, 107fd1e8a1fSTejun Heo int nr_units); 108fd1e8a1fSTejun Heo extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai); 109033e48fbSTejun Heo 110163fa234SKefeng Wang extern void __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, 111fd1e8a1fSTejun Heo void *base_addr); 1128d408b4bSTejun Heo 1134ba6ce25STejun Heo extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, 114c8826dd5STejun Heo size_t atom_size, 115c8826dd5STejun Heo pcpu_fc_cpu_distance_fn_t cpu_distance_fn, 11623f91716SKefeng Wang pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn); 11766c3a757STejun Heo 11808fc4580STejun Heo #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK 11920c03576SKefeng Wang void __init pcpu_populate_pte(unsigned long addr); 120fb435d52STejun Heo extern int __init pcpu_page_first_chunk(size_t reserved_size, 12120c03576SKefeng Wang pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn); 12208fc4580STejun Heo #endif 123d4b95f80STejun Heo 12417197dd4SKees Cook extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align) __alloc_size(1); 125383776faSThomas Gleixner extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr); 12610fad5e4STejun Heo extern bool is_kernel_percpu_address(unsigned long addr); 127f2a8205cSTejun Heo 128bbddff05STejun Heo #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) 129e74e3962STejun Heo extern void __init setup_per_cpu_areas(void); 130e74e3962STejun Heo #endif 131e74e3962STejun Heo 13217197dd4SKees Cook extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp) __alloc_size(1); 13317197dd4SKees Cook extern void __percpu *__alloc_percpu(size_t size, size_t align) __alloc_size(1); 134de380b55STejun Heo extern void free_percpu(void __percpu *__pdata); 13554da6a09SPeter Zijlstra 13654da6a09SPeter Zijlstra DEFINE_FREE(free_percpu, void __percpu *, free_percpu(_T)) 13754da6a09SPeter Zijlstra 138de380b55STejun Heo extern phys_addr_t per_cpu_ptr_to_phys(void *addr); 139de380b55STejun Heo 1405835d96eSTejun Heo #define alloc_percpu_gfp(type, gfp) \ 1415835d96eSTejun Heo (typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \ 1425835d96eSTejun Heo __alignof__(type), gfp) 14364ef291fSTejun Heo #define alloc_percpu(type) \ 1445835d96eSTejun Heo (typeof(type) __percpu *)__alloc_percpu(sizeof(type), \ 1455835d96eSTejun Heo __alignof__(type)) 146f2a8205cSTejun Heo 1477e8a6304SDennis Zhou (Facebook) extern unsigned long pcpu_nr_pages(void); 1487e8a6304SDennis Zhou (Facebook) 1491da177e4SLinus Torvalds #endif /* __LINUX_PERCPU_H */ 150