| #ifndef __LINUX_PERCPU_H |
| #define __LINUX_PERCPU_H |
| |
| #include <linux/preempt.h> |
| #include <linux/slab.h> /* For kmalloc() */ |
| #include <linux/smp.h> |
| #include <linux/cpumask.h> |
| #include <linux/pfn.h> |
| |
| #include <asm/percpu.h> |
| |
| /* enough to cover all DEFINE_PER_CPUs in modules */ |
| #ifdef CONFIG_MODULES |
| #define PERCPU_MODULE_RESERVE (8 << 10) |
| #else |
| #define PERCPU_MODULE_RESERVE 0 |
| #endif |
| |
| #ifndef PERCPU_ENOUGH_ROOM |
| #define PERCPU_ENOUGH_ROOM \ |
| (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ |
| PERCPU_MODULE_RESERVE) |
| #endif |
| |
| /* |
| * Must be an lvalue. Since @var must be a simple identifier, |
| * we force a syntax error here if it isn't. |
| */ |
| #define get_cpu_var(var) (*({ \ |
| extern int simple_identifier_##var(void); \ |
| preempt_disable(); \ |
| &__get_cpu_var(var); })) |
| #define put_cpu_var(var) preempt_enable() |
| |
| #ifdef CONFIG_SMP |
| |
| #ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA |
| |
| /* minimum unit size, also is the maximum supported allocation size */ |
| #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10) |
| |
| /* |
| * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy |
| * back on the first chunk for dynamic percpu allocation if arch is |
| * manually allocating and mapping it for faster access (as a part of |
| * large page mapping for example). |
| * |
| * The following values give between one and two pages of free space |
| * after typical minimal boot (2-way SMP, single disk and NIC) with |
| * both defconfig and a distro config on x86_64 and 32. More |
| * intelligent way to determine this would be nice. |
| */ |
| #if BITS_PER_LONG > 32 |
| #define PERCPU_DYNAMIC_RESERVE (20 << 10) |
| #else |
| #define PERCPU_DYNAMIC_RESERVE (12 << 10) |
| #endif |
| |
| extern void *pcpu_base_addr; |
| extern const unsigned long *pcpu_unit_offsets; |
| |
| struct pcpu_group_info { |
| int nr_units; /* aligned # of units */ |
| unsigned long base_offset; /* base address offset */ |
| unsigned int *cpu_map; /* unit->cpu map, empty |
| * entries contain NR_CPUS */ |
| }; |
| |
| struct pcpu_alloc_info { |
| size_t static_size; |
| size_t reserved_size; |
| size_t dyn_size; |
| size_t unit_size; |
| size_t atom_size; |
| size_t alloc_size; |
| size_t __ai_size; /* internal, don't use */ |
| int nr_groups; /* 0 if grouping unnecessary */ |
| struct pcpu_group_info groups[]; |
| }; |
| |
| enum pcpu_fc { |
| PCPU_FC_AUTO, |
| PCPU_FC_EMBED, |
| PCPU_FC_PAGE, |
| |
| PCPU_FC_NR, |
| }; |
| extern const char *pcpu_fc_names[PCPU_FC_NR]; |
| |
| extern enum pcpu_fc pcpu_chosen_fc; |
| |
| typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size, |
| size_t align); |
| typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size); |
| typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr); |
| typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to); |
| |
| extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, |
| int nr_units); |
| extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai); |
| |
| extern struct pcpu_alloc_info * __init pcpu_build_alloc_info( |
| size_t reserved_size, ssize_t dyn_size, |
| size_t atom_size, |
| pcpu_fc_cpu_distance_fn_t cpu_distance_fn); |
| |
| extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, |
| void *base_addr); |
| |
| #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK |
| extern int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size, |
| size_t atom_size, |
| pcpu_fc_cpu_distance_fn_t cpu_distance_fn, |
| pcpu_fc_alloc_fn_t alloc_fn, |
| pcpu_fc_free_fn_t free_fn); |
| #endif |
| |
| #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK |
| extern int __init pcpu_page_first_chunk(size_t reserved_size, |
| pcpu_fc_alloc_fn_t alloc_fn, |
| pcpu_fc_free_fn_t free_fn, |
| pcpu_fc_populate_pte_fn_t populate_pte_fn); |
| #endif |
| |
| /* |
| * Use this to get to a cpu's version of the per-cpu object |
| * dynamically allocated. Non-atomic access to the current CPU's |
| * version should probably be combined with get_cpu()/put_cpu(). |
| */ |
| #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) |
| |
| extern void *__alloc_reserved_percpu(size_t size, size_t align); |
| |
| #else /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */ |
| |
| struct percpu_data { |
| void *ptrs[1]; |
| }; |
| |
| /* pointer disguising messes up the kmemleak objects tracking */ |
| #ifndef CONFIG_DEBUG_KMEMLEAK |
| #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) |
| #else |
| #define __percpu_disguise(pdata) (struct percpu_data *)(pdata) |
| #endif |
| |
| #define per_cpu_ptr(ptr, cpu) \ |
| ({ \ |
| struct percpu_data *__p = __percpu_disguise(ptr); \ |
| (__typeof__(ptr))__p->ptrs[(cpu)]; \ |
| }) |
| |
| #endif /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */ |
| |
| extern void *__alloc_percpu(size_t size, size_t align); |
| extern void free_percpu(void *__pdata); |
| extern phys_addr_t per_cpu_ptr_to_phys(void *addr); |
| |
| #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA |
| extern void __init setup_per_cpu_areas(void); |
| #endif |
| |
| #else /* CONFIG_SMP */ |
| |
| #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) |
| |
| static inline void *__alloc_percpu(size_t size, size_t align) |
| { |
| /* |
| * Can't easily make larger alignment work with kmalloc. WARN |
| * on it. Larger alignment should only be used for module |
| * percpu sections on SMP for which this path isn't used. |
| */ |
| WARN_ON_ONCE(align > SMP_CACHE_BYTES); |
| return kzalloc(size, GFP_KERNEL); |
| } |
| |
| static inline void free_percpu(void *p) |
| { |
| kfree(p); |
| } |
| |
| static inline void __init setup_per_cpu_areas(void) { } |
| |
| static inline void *pcpu_lpage_remapped(void *kaddr) |
| { |
| return NULL; |
| } |
| |
| #endif /* CONFIG_SMP */ |
| |
| #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \ |
| __alignof__(type)) |
| |
| /* |
| * Optional methods for optimized non-lvalue per-cpu variable access. |
| * |
| * @var can be a percpu variable or a field of it and its size should |
| * equal char, int or long. percpu_read() evaluates to a lvalue and |
| * all others to void. |
| * |
| * These operations are guaranteed to be atomic w.r.t. preemption. |
| * The generic versions use plain get/put_cpu_var(). Archs are |
| * encouraged to implement single-instruction alternatives which don't |
| * require preemption protection. |
| */ |
| #ifndef percpu_read |
| # define percpu_read(var) \ |
| ({ \ |
| typeof(per_cpu_var(var)) __tmp_var__; \ |
| __tmp_var__ = get_cpu_var(var); \ |
| put_cpu_var(var); \ |
| __tmp_var__; \ |
| }) |
| #endif |
| |
| #define __percpu_generic_to_op(var, val, op) \ |
| do { \ |
| get_cpu_var(var) op val; \ |
| put_cpu_var(var); \ |
| } while (0) |
| |
| #ifndef percpu_write |
| # define percpu_write(var, val) __percpu_generic_to_op(var, (val), =) |
| #endif |
| |
| #ifndef percpu_add |
| # define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=) |
| #endif |
| |
| #ifndef percpu_sub |
| # define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=) |
| #endif |
| |
| #ifndef percpu_and |
| # define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=) |
| #endif |
| |
| #ifndef percpu_or |
| # define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=) |
| #endif |
| |
| #ifndef percpu_xor |
| # define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=) |
| #endif |
| |
| #endif /* __LINUX_PERCPU_H */ |