#include <assert.h>
#include "opj_includes.h"

Data Structures
struct	opj_tls_key_val_t

struct	opj_tls_t

struct	opj_worker_thread_job_t

struct	opj_worker_thread_t

struct	opj_job_list_t

struct	opj_worker_thread_list_t

struct	opj_thread_pool_t

Typedefs
typedef struct opj_job_list_t	opj_job_list_t

typedef struct opj_worker_thread_list_t	opj_worker_thread_list_t

Enumerations
enum	opj_worker_thread_state { OPJWTS_OK, OPJWTS_STOP, OPJWTS_ERROR }

Functions
OPJ_BOOL OPJ_CALLCONV	opj_has_thread_support (void)
	Returns if the library is built with thread support. More...

int OPJ_CALLCONV	opj_get_num_cpus (void)
	Return the number of virtual CPUs. More...

opj_mutex_t *	opj_mutex_create (void)
	Creates a mutex. More...

void	opj_mutex_lock (opj_mutex_t *mutex)
	Lock/acquire the mutex. More...

void	opj_mutex_unlock (opj_mutex_t *mutex)
	Unlock/release the mutex. More...

void	opj_mutex_destroy (opj_mutex_t *mutex)
	Destroy a mutex. More...

opj_cond_t *	opj_cond_create (void)
	Creates a condition. More...

void	opj_cond_wait (opj_cond_t cond, opj_mutex_t mutex)
	Wait for the condition to be signaled. More...

void	opj_cond_signal (opj_cond_t *cond)
	Signal waiting threads on a condition. More...

void	opj_cond_destroy (opj_cond_t *cond)
	Destroy a condition. More...

opj_thread_t *	opj_thread_create (opj_thread_fn thread_fn, void *user_data)
	Creates a new thread. More...

void	opj_thread_join (opj_thread_t *thread)
	Wait for a thread to be finished and release associated resources to the thread handle. More...

static opj_tls_t *	opj_tls_new (void)

static void	opj_tls_destroy (opj_tls_t *tls)

void *	opj_tls_get (opj_tls_t *tls, int key)
	Get a thread local value corresponding to the provided key. More...

OPJ_BOOL	opj_tls_set (opj_tls_t tls, int key, void value, opj_tls_free_func opj_free_func)
	Set a thread local value corresponding to the provided key. More...

static OPJ_BOOL	opj_thread_pool_setup (opj_thread_pool_t *tp, int num_threads)

static opj_worker_thread_job_t *	opj_thread_pool_get_next_job (opj_thread_pool_t tp, opj_worker_thread_t worker_thread, OPJ_BOOL signal_job_finished)

opj_thread_pool_t *	opj_thread_pool_create (int num_threads)
	Create a new thread pool. More...

static void	opj_worker_thread_function (void *user_data)

OPJ_BOOL	opj_thread_pool_submit_job (opj_thread_pool_t tp, opj_job_fn job_fn, void user_data)
	Submit a new job to be run by one of the thread in the thread pool. More...

void	opj_thread_pool_wait_completion (opj_thread_pool_t *tp, int max_remaining_jobs)
	Wait that no more than max_remaining_jobs jobs are remaining in the queue of the thread pool. More...

int	opj_thread_pool_get_thread_count (opj_thread_pool_t *tp)
	Return the number of threads associated with the thread pool. More...

void	opj_thread_pool_destroy (opj_thread_pool_t *tp)
	Destroy a thread pool. More...

Typedef Documentation

◆ opj_job_list_t

typedef struct opj_job_list_t opj_job_list_t

◆ opj_worker_thread_list_t

typedef struct opj_worker_thread_list_t opj_worker_thread_list_t

Enumeration Type Documentation

◆ opj_worker_thread_state

enum opj_worker_thread_state

Enumerator
OPJWTS_OK
OPJWTS_STOP
OPJWTS_ERROR

Function Documentation

◆ opj_cond_create()

opj_cond_t* opj_cond_create ( void )

Creates a condition.

Returns: the condition or NULL in case of error (can for example happen if the library is built without thread support)

Referenced by opj_thread_pool_setup().

◆ opj_cond_destroy()

void opj_cond_destroy ( opj_cond_t * cond )

Destroy a condition.

Parameters

cond	the condition to destroy.

Referenced by opj_thread_pool_destroy(), and opj_thread_pool_setup().

◆ opj_cond_signal()

void opj_cond_signal ( opj_cond_t * cond )

Signal waiting threads on a condition.

One of the thread waiting with opj_cond_wait() will be waken up. It is strongly advised that this call is done with the mutex that is used by opj_cond_wait(), in a acquired state.

Parameters

cond	the condition to signal.

Referenced by opj_thread_pool_destroy(), opj_thread_pool_get_next_job(), and opj_thread_pool_submit_job().

◆ opj_cond_wait()

void opj_cond_wait	(	opj_cond_t *	cond,
		opj_mutex_t *	mutex
	)

Wait for the condition to be signaled.

The semantics is the same as the POSIX pthread_cond_wait. The provided mutex must be acquired before calling this function, and released afterwards. The mutex will be released by this function while it must wait for the condition and reacquired afterwards. In some particular situations, the function might return even if the condition is not signaled with opj_cond_signal(), hence the need to check with an application level mechanism.

Waiting thread :

opj_mutex_lock(mutex);
while( !some_application_level_condition )
{
    opj_cond_wait(cond, mutex);
}
opj_mutex_unlock(mutex);

Signaling thread :

opj_mutex_lock(mutex);
some_application_level_condition = TRUE;
opj_cond_signal(cond);
opj_mutex_unlock(mutex);

Parameters

cond	the condition to wait.
mutex	the mutex (in acquired state before calling this function)

Referenced by opj_thread_pool_get_next_job(), opj_thread_pool_setup(), opj_thread_pool_submit_job(), and opj_thread_pool_wait_completion().

◆ opj_get_num_cpus()

int OPJ_CALLCONV opj_get_num_cpus ( void )

Return the number of virtual CPUs.

Referenced by opj_j2k_get_default_thread_count().

◆ opj_has_thread_support()

OPJ_BOOL OPJ_CALLCONV opj_has_thread_support ( void )

Returns if the library is built with thread support.

OPJ_TRUE if mutex, condition, thread, thread pool are available.

References OPJ_FALSE.

Referenced by opj_j2k_get_default_thread_count(), and opj_j2k_set_threads().

◆ opj_mutex_create()

opj_mutex_t* opj_mutex_create ( void )

Creates a mutex.

Returns: the mutex or NULL in case of error (can for example happen if the library is built without thread support)

Referenced by opj_t1_encode_cblks(), opj_tcd_t1_decode(), opj_thread_pool_create(), and opj_thread_pool_setup().

◆ opj_mutex_destroy()

void opj_mutex_destroy ( opj_mutex_t * mutex )

Destroy a mutex.

Parameters

mutex the mutex to destroy.

Referenced by opj_t1_encode_cblks(), opj_tcd_t1_decode(), opj_thread_pool_destroy(), and opj_thread_pool_setup().

◆ opj_mutex_lock()

void opj_mutex_lock ( opj_mutex_t * mutex )

Lock/acquire the mutex.

Parameters

mutex the mutex to acquire.

Referenced by opj_t1_cblk_encode_processor(), opj_t1_clbl_decode_processor(), opj_t1_decode_cblk(), opj_t1_ht_decode_cblk(), opj_thread_pool_destroy(), opj_thread_pool_get_next_job(), opj_thread_pool_setup(), opj_thread_pool_submit_job(), and opj_thread_pool_wait_completion().

◆ opj_mutex_unlock()

void opj_mutex_unlock ( opj_mutex_t * mutex )

Unlock/release the mutex.

Parameters

mutex the mutex to release.

Referenced by opj_t1_cblk_encode_processor(), opj_t1_clbl_decode_processor(), opj_t1_decode_cblk(), opj_t1_ht_decode_cblk(), opj_thread_pool_destroy(), opj_thread_pool_get_next_job(), opj_thread_pool_setup(), opj_thread_pool_submit_job(), and opj_thread_pool_wait_completion().

◆ opj_thread_create()

opj_thread_t* opj_thread_create	(	opj_thread_fn	thread_fn,
		void *	user_data
	)

Creates a new thread.

Parameters

thread_fn	Function to run in the new thread.
user_data	user data provided to the thread function. Might be NULL.

Returns: a thread handle or NULL in case of failure (can for example happen if the library is built without thread support)

Referenced by opj_thread_pool_setup().

◆ opj_thread_join()

void opj_thread_join ( opj_thread_t * thread )

Wait for a thread to be finished and release associated resources to the thread handle.

Parameters

thread the thread to wait for being finished.

Referenced by opj_thread_pool_destroy().

◆ opj_thread_pool_create()

opj_thread_pool_t* opj_thread_pool_create ( int num_threads )

Create a new thread pool.

num_thread must nominally be >= 1 to create a real thread pool. If num_threads is negative or null, then a dummy thread pool will be created. All functions operating on the thread pool will work, but job submission will be run synchronously in the calling thread.

Parameters

num_threads the number of threads to allocate for this thread pool.

Returns: a thread pool handle, or NULL in case of failure (can for example happen if the library is built without thread support)

References opj_thread_pool_t::mutex, opj_calloc(), opj_free(), opj_mutex_create(), opj_thread_pool_destroy(), opj_thread_pool_setup(), opj_tls_new(), OPJWTS_OK, opj_thread_pool_t::state, and opj_thread_pool_t::tls.

Referenced by main(), opj_j2k_create_compress(), opj_j2k_create_decompress(), and opj_j2k_set_threads().

◆ opj_thread_pool_destroy()

void opj_thread_pool_destroy ( opj_thread_pool_t * tp )

Destroy a thread pool.

Parameters

tp	the thread pool handle.

References opj_worker_thread_t::cond, opj_thread_pool_t::cond, opj_worker_thread_t::mutex, opj_thread_pool_t::mutex, opj_worker_thread_list_t::next, opj_cond_destroy(), opj_cond_signal(), opj_free(), opj_mutex_destroy(), opj_mutex_lock(), opj_mutex_unlock(), opj_thread_join(), opj_thread_pool_wait_completion(), opj_tls_destroy(), OPJWTS_STOP, opj_thread_pool_t::state, opj_worker_thread_t::thread, opj_thread_pool_t::tls, opj_thread_pool_t::waiting_worker_thread_list, opj_thread_pool_t::worker_threads, and opj_thread_pool_t::worker_threads_count.

Referenced by main(), opj_j2k_destroy(), opj_j2k_set_threads(), and opj_thread_pool_create().

◆ opj_thread_pool_get_next_job()

static opj_worker_thread_job_t * opj_thread_pool_get_next_job	(	opj_thread_pool_t *	tp,
		opj_worker_thread_t *	worker_thread,
		OPJ_BOOL	signal_job_finished
	)

static

◆ opj_thread_pool_get_thread_count()

int opj_thread_pool_get_thread_count ( opj_thread_pool_t * tp )

Return the number of threads associated with the thread pool.

Parameters

tp	the thread pool handle.

Returns: number of threads associated with the thread pool.

References opj_thread_pool_t::worker_threads_count.

Referenced by opj_dwt_decode_tile(), opj_dwt_decode_tile_97(), opj_dwt_encode_procedure(), and opj_t1_decode_cblks().

◆ opj_thread_pool_setup()

static OPJ_BOOL opj_thread_pool_setup	(	opj_thread_pool_t *	tp,
		int	num_threads
	)

static

◆ opj_thread_pool_submit_job()

OPJ_BOOL opj_thread_pool_submit_job	(	opj_thread_pool_t *	tp,
		opj_job_fn	job_fn,
		void *	user_data
	)

Submit a new job to be run by one of the thread in the thread pool.

The job ( thread_fn, user_data ) will be added in the queue of jobs managed by the thread pool, and run by the first thread that is no longer busy.

Parameters

tp	the thread pool handle.
job_fn	Function to run. Must not be NULL.
user_data	User data provided to thread_fn.

Returns: OPJ_TRUE if the job was successfully submitted.

References opj_worker_thread_t::cond, opj_thread_pool_t::cond, opj_job_list_t::job, opj_worker_thread_job_t::job_fn, opj_thread_pool_t::job_queue, opj_worker_thread_t::marked_as_waiting, opj_worker_thread_t::mutex, opj_thread_pool_t::mutex, opj_job_list_t::next, opj_worker_thread_list_t::next, opj_cond_signal(), opj_cond_wait(), OPJ_FALSE, opj_free(), opj_malloc(), opj_mutex_lock(), opj_mutex_unlock(), OPJ_TRUE, opj_thread_pool_t::pending_jobs_count, opj_thread_pool_t::signaling_threshold, opj_thread_pool_t::tls, opj_worker_thread_job_t::user_data, opj_thread_pool_t::waiting_worker_thread_count, opj_thread_pool_t::waiting_worker_thread_list, opj_worker_thread_list_t::worker_thread, and opj_thread_pool_t::worker_threads_count.

Referenced by opj_dwt_decode_tile(), opj_dwt_decode_tile_97(), opj_dwt_encode_procedure(), opj_t1_decode_cblks(), and opj_t1_encode_cblks().

◆ opj_thread_pool_wait_completion()

void opj_thread_pool_wait_completion	(	opj_thread_pool_t *	tp,
		int	max_remaining_jobs
	)

Wait that no more than max_remaining_jobs jobs are remaining in the queue of the thread pool.

The aim of this function is to avoid submitting too many jobs while the thread pool cannot cope fast enough with them, which would result potentially in out-of-memory situations with too many job descriptions being queued.

Parameters