include/linux/percpu.h
Source file repositories/reference/linux-study-clean/include/linux/percpu.h
File Facts
- System
- Linux kernel
- Corpus path
include/linux/percpu.h- Extension
.h- Size
- 5333 bytes
- Lines
- 166
- Domain
- Core OS
- Bucket
- Core Kernel Interface
- Inferred role
- Core OS: implementation source
- Status
- source implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/alloc_tag.hlinux/cleanup.hlinux/compiler_types.hlinux/init.hlinux/mmdebug.hlinux/pfn.hlinux/preempt.hlinux/sched.hlinux/smp.hasm/percpu.h
Detected Declarations
struct pcpu_group_infostruct pcpu_alloc_infoenum pcpu_fc
Annotated Snippet
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 * const pcpu_fc_names[PCPU_FC_NR];
extern enum pcpu_fc pcpu_chosen_fc;
typedef int (pcpu_fc_cpu_to_node_fn_t)(int cpu);
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 void __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
void *base_addr);
extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
size_t atom_size,
pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn);
#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
void __init pcpu_populate_pte(unsigned long addr);
extern int __init pcpu_page_first_chunk(size_t reserved_size,
pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn);
#endif
extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr);
extern bool is_kernel_percpu_address(unsigned long addr);
#if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
extern void __init setup_per_cpu_areas(void);
#endif
extern void __percpu *pcpu_alloc_noprof(size_t size, size_t align, bool reserved,
gfp_t gfp) __alloc_size(1);
#define __alloc_percpu_gfp(_size, _align, _gfp) \
alloc_hooks(pcpu_alloc_noprof(_size, _align, false, _gfp))
#define __alloc_percpu(_size, _align) \
alloc_hooks(pcpu_alloc_noprof(_size, _align, false, GFP_KERNEL))
#define __alloc_reserved_percpu(_size, _align) \
alloc_hooks(pcpu_alloc_noprof(_size, _align, true, GFP_KERNEL))
#define alloc_percpu_gfp(type, gfp) \
(typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \
__alignof__(type), gfp)
#define alloc_percpu(type) \
(typeof(type) __percpu *)__alloc_percpu(sizeof(type), \
__alignof__(type))
#define alloc_percpu_noprof(type) \
((typeof(type) __percpu *)pcpu_alloc_noprof(sizeof(type), \
__alignof__(type), false, GFP_KERNEL))
extern void free_percpu(void __percpu *__pdata);
DEFINE_FREE(free_percpu, void __percpu *, free_percpu(_T))
extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
extern unsigned long pcpu_nr_pages(void);
#endif /* __LINUX_PERCPU_H */
Annotation
- Immediate include surface: `linux/alloc_tag.h`, `linux/cleanup.h`, `linux/compiler_types.h`, `linux/init.h`, `linux/mmdebug.h`, `linux/pfn.h`, `linux/preempt.h`, `linux/sched.h`.
- Detected declarations: `struct pcpu_group_info`, `struct pcpu_alloc_info`, `enum pcpu_fc`.
- Atlas domain: Core OS / Core Kernel Interface.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.