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dm vdo uds-threads: eliminate uds_*_semaphore interfaces

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The implementation of thread 'barrier' data structure does not require
overdone private semaphore wrappers.  Also rename the barrier
structure's 'mutex' member (a semaphore) to 'lock'.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
This commit is contained in:
Mike Snitzer 2024-02-09 10:46:04 -06:00
parent 9d87418945
commit 2d98aa1780
2 changed files with 15 additions and 44 deletions
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55
drivers/md/dm-vdo/uds-threads.c
View File

@ -136,19 +136,7 @@ int uds_join_threads(struct thread *thread)
return UDS_SUCCESS;
}
static inline int __must_check uds_initialize_semaphore(struct semaphore *semaphore,
unsigned int value)
{
sema_init(semaphore, value);
return UDS_SUCCESS;
}
static inline int uds_destroy_semaphore(struct semaphore *semaphore)
{
return UDS_SUCCESS;
}
static inline void uds_acquire_semaphore(struct semaphore *semaphore)
static inline void __down(struct semaphore *semaphore)
{
/*
* Do not use down(semaphore). Instead use down_interruptible so that
@ -169,53 +157,36 @@ static inline void uds_acquire_semaphore(struct semaphore *semaphore)
}
}
static inline void uds_release_semaphore(struct semaphore *semaphore)
{
up(semaphore);
}
int uds_initialize_barrier(struct barrier *barrier, unsigned int thread_count)
{
int result;
/* FIXME: must cleanup, uds_initialize_semaphore never fails! */
result = uds_initialize_semaphore(&barrier->mutex, 1);
if (result != UDS_SUCCESS)
return result;
sema_init(&barrier->lock, 1);
barrier->arrived = 0;
barrier->thread_count = thread_count;
return uds_initialize_semaphore(&barrier->wait, 0);
sema_init(&barrier->wait, 0);
return UDS_SUCCESS;
}
int uds_destroy_barrier(struct barrier *barrier)
{
int result;
result = uds_destroy_semaphore(&barrier->mutex);
if (result != UDS_SUCCESS)
return result;
return uds_destroy_semaphore(&barrier->wait);
return UDS_SUCCESS;
}
int uds_enter_barrier(struct barrier *barrier)
{
bool last_thread;
uds_acquire_semaphore(&barrier->mutex);
last_thread = (++barrier->arrived == barrier->thread_count);
if (last_thread) {
__down(&barrier->lock);
if (++barrier->arrived == barrier->thread_count) {
/* last thread */
int i;
for (i = 1; i < barrier->thread_count; i++)
uds_release_semaphore(&barrier->wait);
up(&barrier->wait);
barrier->arrived = 0;
uds_release_semaphore(&barrier->mutex);
up(&barrier->lock);
} else {
uds_release_semaphore(&barrier->mutex);
uds_acquire_semaphore(&barrier->wait);
up(&barrier->lock);
__down(&barrier->wait);
}
return UDS_SUCCESS;

4
drivers/md/dm-vdo/uds-threads.h
View File

@ -25,8 +25,8 @@ struct cond_var {
struct thread;
struct barrier {
/* Mutex for this barrier object */
struct semaphore mutex;
/* Lock for this barrier object */
struct semaphore lock;
/* Semaphore for threads waiting at the barrier */
struct semaphore wait;
/* Number of threads which have arrived */