tools/perf/util/rwsem.c
Source file repositories/reference/linux-study-clean/tools/perf/util/rwsem.c
File Facts
- System
- Linux kernel
- Corpus path
tools/perf/util/rwsem.c- Extension
.c- Size
- 1273 bytes
- Lines
- 72
- 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.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
util.hrwsem.hmutex.h
Detected Declarations
function init_rwsemfunction exit_rwsem
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
#include "util.h"
#include "rwsem.h"
#if RWS_ERRORCHECK
#include "mutex.h"
#endif
int init_rwsem(struct rw_semaphore *sem)
{
#if RWS_ERRORCHECK
mutex_init(&sem->mtx);
return 0;
#else
return pthread_rwlock_init(&sem->lock, NULL);
#endif
}
int exit_rwsem(struct rw_semaphore *sem)
{
#if RWS_ERRORCHECK
mutex_destroy(&sem->mtx);
return 0;
#else
return pthread_rwlock_destroy(&sem->lock);
#endif
}
int down_read(struct rw_semaphore *sem)
NO_THREAD_SAFETY_ANALYSIS
{
#if RWS_ERRORCHECK
mutex_lock(&sem->mtx);
return 0;
#else
return perf_singlethreaded ? 0 : pthread_rwlock_rdlock(&sem->lock);
#endif
}
int up_read(struct rw_semaphore *sem)
NO_THREAD_SAFETY_ANALYSIS
{
#if RWS_ERRORCHECK
mutex_unlock(&sem->mtx);
return 0;
#else
return perf_singlethreaded ? 0 : pthread_rwlock_unlock(&sem->lock);
#endif
}
int down_write(struct rw_semaphore *sem)
NO_THREAD_SAFETY_ANALYSIS
{
#if RWS_ERRORCHECK
mutex_lock(&sem->mtx);
return 0;
#else
return perf_singlethreaded ? 0 : pthread_rwlock_wrlock(&sem->lock);
#endif
}
int up_write(struct rw_semaphore *sem)
NO_THREAD_SAFETY_ANALYSIS
{
#if RWS_ERRORCHECK
mutex_unlock(&sem->mtx);
return 0;
#else
return perf_singlethreaded ? 0 : pthread_rwlock_unlock(&sem->lock);
#endif
}
Annotation
- Immediate include surface: `util.h`, `rwsem.h`, `mutex.h`.
- Detected declarations: `function init_rwsem`, `function exit_rwsem`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
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.