tools/perf/util/rwsem.h

File Facts

System

Linux kernel

Corpus path

tools/perf/util/rwsem.h

Extension

.h

Size

706 bytes

Lines

31

Domain

Support Tooling And Documentation

Bucket

tools

Inferred role

Support Tooling And Documentation: implementation source

Status

source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• pthread.h
• mutex.h

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

#ifndef _PERF_RWSEM_H
#define _PERF_RWSEM_H

#include <pthread.h>
#include "mutex.h"

/*
 * Mutexes have additional error checking. Enable to use a mutex rather than a
 * rwlock for debugging.
 */
#define RWS_ERRORCHECK 0

struct LOCKABLE rw_semaphore {
#if RWS_ERRORCHECK
	struct mutex mtx;
#else
	pthread_rwlock_t lock;
#endif
};

int init_rwsem(struct rw_semaphore *sem);
int exit_rwsem(struct rw_semaphore *sem);

int down_read(struct rw_semaphore *sem) SHARED_LOCK_FUNCTION(sem);
int up_read(struct rw_semaphore *sem) UNLOCK_FUNCTION(sem);

int down_write(struct rw_semaphore *sem) EXCLUSIVE_LOCK_FUNCTION(sem);
int up_write(struct rw_semaphore *sem) UNLOCK_FUNCTION(sem);

#endif /* _PERF_RWSEM_H */

Annotation

• Immediate include surface: `pthread.h`, `mutex.h`.
• Atlas domain: Support Tooling And Documentation / tools.
• 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.