THREADS: tools to create and manage a thread pool

Data Structures
struct	THREAD_POOL
	Structure of a trhead pool. More...
struct	THREAD_POOL_NODE
	A thread pool node. More...
struct	THREAD_WAITING_PROC
	Structure of a waiting process item. More...

Macros
#define	DIRECT_PROC   2
	processing mode for added func, direct start More...
#define	EXITED_THREAD   256
	indicate that the pool is off, all jobs have been consumed More...
#define	EXITING_THREAD   128
	indicate that the pool is exiting, unfinished jobs will finish and the pool will exit the threads and enter the EXITED state More...
#define	IDLE_PROC   8
	status of a thread which is waiting for some proc More...
#define	NO_LOCK   512
	if passed to add_threaded_process, skip main table lock in case we are in a func which is already locking it More...
#define	NOQUEUE   4
	processing mode for waiting_list: do not readd the work in queue More...
#define	RUNNING_PROC   32
	status of a thread which proc is currently running More...
#define	RUNNING_THREAD   64
	indicate that the pool is running and ready to use More...
#define	SYNCED_PROC   1
	processing mode for added func, synced start More...
#define	WAITING_PROC   16
	status of a thread who have proc waiting to be processed More...

Functions
int	add_threaded_process (THREAD_POOL *thread_pool, void *(*func_ptr)(void *param), void *param, int mode)
	add a function and params to a thread pool More...
int	destroy_threaded_pool (THREAD_POOL **thread_pool, int delay)
	delete a thread_pool, exit the threads and free the structs More...
int	get_nb_cpu_cores ()
	get number of core of current system More...
THREAD_POOL *	new_thread_pool (int nbmaxthr, int nb_max_waiting)
	Create a new pool of nbmaxthr threads. More...
int	refresh_thread_pool (THREAD_POOL *thread_pool)
	try to add some waiting DIRECT_PROCs on some free thread slots, else do nothing More...
int	start_threaded_pool (THREAD_POOL *thread_pool)
	Launch the process waiting for exectution in the thread pool. More...
int	wait_for_synced_threaded_pool (THREAD_POOL *thread_pool)
	wait for all the launched process, blocking but light on the CPU as there is no polling More...
int	wait_for_threaded_pool (THREAD_POOL *thread_pool, int delay)
	Wait for all the launched process in the thread pool to terminate. More...

Detailed Description

---

Data Structure Documentation

THREAD_POOL

struct THREAD_POOL

Structure of a trhead pool.

Examples

ex_fluid.c, ex_network.c, and ex_threads.c.

Definition at line 80 of file n_thread_pool.h.

Collaboration diagram for THREAD_POOL:

Data Fields
pthread_mutex_t	lock	mutex to prevent mutual access of waiting_list parameters
int	max_threads	Maximum number of running threads in the list.
int	nb_actives	number of threads actually doing a proc
int	nb_max_waiting	Maximum number of waiting procedures int the list, 0 or -1 for unlimited.
sem_t	nb_tasks	semaphore to store the number of tasks
THREAD_POOL_NODE **	thread_list	Dynamically allocated but fixed size thread array.
LIST *	waiting_list	Waiting list handling.

THREAD_POOL_NODE

struct THREAD_POOL_NODE

A thread pool node.

Definition at line 48 of file n_thread_pool.h.

Collaboration diagram for THREAD_POOL_NODE:

Data Fields
void *(*	func )(void *param)
	function to call in the thread More...
pthread_mutex_t	lock
	mutex to prevent mutual access of node parameters More...
void *	param
	if not NULL , passed as argument More...
int	state
	state of the proc , RUNNING_PROC when it is busy processing func( param) , IDLE_PROC when it waits for some func and param to process , WAITING_PROC when it has things waiting to be processed More...
sem_t	th_end
	thread ending semaphore More...
sem_t	th_start
	thread starting semaphore More...
pthread_t	thr
	thread id More...
struct THREAD_POOL *	thread_pool
	pointer to assigned thread pool More...
int	thread_state
	state of the managing thread , RUNNING_THREAD, EXITING_THREAD, EXITED_THREAD More...
int	type
	SYNCED or DIRECT process start. More...

Field Documentation

func

void *(* THREAD_POOL_NODE::func) (void *param)

function to call in the thread

Definition at line 51 of file n_thread_pool.h.

lock

pthread_mutex_t THREAD_POOL_NODE::lock

mutex to prevent mutual access of node parameters

Definition at line 71 of file n_thread_pool.h.

param

void* THREAD_POOL_NODE::param

if not NULL , passed as argument

Definition at line 54 of file n_thread_pool.h.

state

int THREAD_POOL_NODE::state

state of the proc , RUNNING_PROC when it is busy processing func( param) , IDLE_PROC when it waits for some func and param to process , WAITING_PROC when it has things waiting to be processed

Definition at line 59 of file n_thread_pool.h.

th_end

sem_t THREAD_POOL_NODE::th_end

thread ending semaphore

Definition at line 68 of file n_thread_pool.h.

th_start

sem_t THREAD_POOL_NODE::th_start

thread starting semaphore

Definition at line 66 of file n_thread_pool.h.

thr

pthread_t THREAD_POOL_NODE::thr

thread id

Definition at line 63 of file n_thread_pool.h.

thread_pool

struct THREAD_POOL* THREAD_POOL_NODE::thread_pool

pointer to assigned thread pool

Definition at line 74 of file n_thread_pool.h.

thread_state

int THREAD_POOL_NODE::thread_state

state of the managing thread , RUNNING_THREAD, EXITING_THREAD, EXITED_THREAD

Definition at line 61 of file n_thread_pool.h.

type

int THREAD_POOL_NODE::type

SYNCED or DIRECT process start.

Definition at line 57 of file n_thread_pool.h.

THREAD_WAITING_PROC

struct THREAD_WAITING_PROC

Structure of a waiting process item.

Definition at line 106 of file n_thread_pool.h.

Collaboration diagram for THREAD_WAITING_PROC:

Data Fields
void *(*	func )(void *param)
	function to call in the thread More...
void *	param
	if not NULL , passed as argument More...

Field Documentation

func

void *(* THREAD_WAITING_PROC::func) (void *param)

function to call in the thread

Definition at line 109 of file n_thread_pool.h.

param

void* THREAD_WAITING_PROC::param

if not NULL , passed as argument

Definition at line 111 of file n_thread_pool.h.

Macro Definition Documentation

DIRECT_PROC

#define DIRECT_PROC   2

processing mode for added func, direct start

Examples

ex_network.c, and ex_threads.c.

Definition at line 29 of file n_thread_pool.h.

EXITED_THREAD

#define EXITED_THREAD   256

indicate that the pool is off, all jobs have been consumed

Definition at line 43 of file n_thread_pool.h.

EXITING_THREAD

#define EXITING_THREAD   128

indicate that the pool is exiting, unfinished jobs will finish and the pool will exit the threads and enter the EXITED state

Definition at line 41 of file n_thread_pool.h.

IDLE_PROC

#define IDLE_PROC   8

status of a thread which is waiting for some proc

Definition at line 33 of file n_thread_pool.h.

NO_LOCK

#define NO_LOCK   512

if passed to add_threaded_process, skip main table lock in case we are in a func which is already locking it

Definition at line 45 of file n_thread_pool.h.

NOQUEUE

#define NOQUEUE   4

processing mode for waiting_list: do not readd the work in queue

Definition at line 31 of file n_thread_pool.h.

RUNNING_PROC

#define RUNNING_PROC   32

status of a thread which proc is currently running

Definition at line 37 of file n_thread_pool.h.

RUNNING_THREAD

#define RUNNING_THREAD   64

indicate that the pool is running and ready to use

Definition at line 39 of file n_thread_pool.h.

SYNCED_PROC

#define SYNCED_PROC   1

processing mode for added func, synced start

Definition at line 27 of file n_thread_pool.h.

WAITING_PROC

#define WAITING_PROC   16

status of a thread who have proc waiting to be processed

Definition at line 35 of file n_thread_pool.h.

Function Documentation

add_threaded_process()

int add_threaded_process	(	THREAD_POOL *	thread_pool,
		void *(*)(void *param)	func_ptr,
		void *	param,
		int	mode
	)

add a function and params to a thread pool

Parameters

thread_pool	The target thread pool
func_ptr	The function pointer to launch
param	Eventual parameter struct to pass to the function
mode	SYNCED_PROC: added to pool, but wait for a start call with other waiting procs. DIRECT_PROC: the function actually starts as quick as possible

Returns

TRUE or FALSE

Definition at line 205 of file n_thread_pool.c.

References DIRECT_PROC, IDLE_PROC, list_push(), LOG_DEBUG, LOG_ERR, Malloc, n_log, NO_LOCK, NOQUEUE, RUNNING_THREAD, SYNCED_PROC, and WAITING_PROC.

Referenced by n_fluid_simulate_threaded(), n_vigenere_cypher(), and refresh_thread_pool().

Here is the call graph for this function:

Here is the caller graph for this function:

destroy_threaded_pool()

int destroy_threaded_pool	(	THREAD_POOL **	pool,
		int	delay
	)

delete a thread_pool, exit the threads and free the structs

Parameters

pool	The THREAD_POOL *object to kill
delay	The THREAD_POOL *object to kill

Returns

TRUE or FALSE

Definition at line 403 of file n_thread_pool.c.

References __n_assert, EXITING_THREAD, Free, IDLE_PROC, list_destroy(), and u_sleep().

Referenced by n_vigenere_cypher().

Here is the call graph for this function:

Here is the caller graph for this function:

get_nb_cpu_cores()

int get_nb_cpu_cores

(

)

get number of core of current system

Returns

The number of cores or -1 if the system command is not supported

Definition at line 27 of file n_thread_pool.c.

Referenced by new_n_fluid().

Here is the caller graph for this function:

new_thread_pool()

THREAD_POOL * new_thread_pool	(	int	nbmaxthr,
		int	nb_max_waiting
	)

Create a new pool of nbmaxthr threads.

Parameters

nbmaxthr	number of active threads in the pool
nb_max_waiting	max number of waiting procs in the pool. Negative or zero value for no limit

Returns

NULL or a new trhead pool object

Definition at line 125 of file n_thread_pool.c.

References Free, IDLE_PROC, LOG_ERR, Malloc, n_log, new_generic_list(), RUNNING_THREAD, and thread_pool_processing_function().

Referenced by n_vigenere_cypher().

Here is the call graph for this function:

Here is the caller graph for this function:

refresh_thread_pool()

int refresh_thread_pool

(

THREAD_POOL *

thread_pool

)

try to add some waiting DIRECT_PROCs on some free thread slots, else do nothing

Parameters

thread_pool

The thread pool to refresh

Returns

TRUE or FALSE

Definition at line 469 of file n_thread_pool.c.

References __n_assert, add_threaded_process(), DIRECT_PROC, Free, NO_LOCK, NOQUEUE, remove_list_node, and RUNNING_PROC.

Referenced by n_fluid_simulate_threaded(), n_vigenere_cypher(), thread_pool_processing_function(), and wait_for_threaded_pool().

Here is the call graph for this function:

Here is the caller graph for this function:

start_threaded_pool()

int start_threaded_pool

(

THREAD_POOL *

thread_pool

)

Launch the process waiting for exectution in the thread pool.

Parameters

thread_pool

The thread pool to launche

Returns

TRUE or FALSE

Definition at line 286 of file n_thread_pool.c.

References LOG_ERR, n_log, SYNCED_PROC, and WAITING_PROC.

Referenced by n_fluid_simulate_threaded().

Here is the caller graph for this function:

wait_for_synced_threaded_pool()

int wait_for_synced_threaded_pool

(

THREAD_POOL *

thread_pool

)

wait for all the launched process, blocking but light on the CPU as there is no polling

Parameters

thread_pool

The thread pool to wait

Returns

TRUE or FALSE

Definition at line 326 of file n_thread_pool.c.

References __n_assert, LOG_ERR, and n_log.

Referenced by n_fluid_simulate_threaded().

Here is the caller graph for this function:

wait_for_threaded_pool()

int wait_for_threaded_pool	(	THREAD_POOL *	thread_pool,
		int	delay
	)

Wait for all the launched process in the thread pool to terminate.

Parameters

thread_pool	The thread pool to wait
delay	time between each check

Returns

TRUE or FALSE

Definition at line 352 of file n_thread_pool.c.

References IDLE_PROC, refresh_thread_pool(), and u_sleep().

Referenced by n_vigenere_cypher().

Here is the call graph for this function:

Here is the caller graph for this function: