Added thread pool to aid in clean daemon shutdown

This commit is contained in:
John Jones 2017-04-17 14:02:33 -05:00
parent 427b5c948f
commit a2a08156a7
11 changed files with 852 additions and 20 deletions

View file

@ -19,6 +19,7 @@
#include "libp2p/routing/dht_protocol.h" #include "libp2p/routing/dht_protocol.h"
#include "ipfs/merkledag/merkledag.h" #include "ipfs/merkledag/merkledag.h"
#include "ipfs/merkledag/node.h" #include "ipfs/merkledag/node.h"
#include "ipfs/util/thread_pool.h"
#define BUF_SIZE 4096 #define BUF_SIZE 4096
@ -41,7 +42,7 @@ int protocol_compare(unsigned char* incoming, size_t incoming_size, const char*
/** /**
* We've received a connection. Find out what they want * We've received a connection. Find out what they want
*/ */
void *ipfs_null_connection (void *ptr) void ipfs_null_connection (void *ptr)
{ {
struct null_connection_params *connection_param = NULL; struct null_connection_params *connection_param = NULL;
@ -62,10 +63,16 @@ void *ipfs_null_connection (void *ptr)
// check if they're looking for an upgrade (i.e. secio) // check if they're looking for an upgrade (i.e. secio)
unsigned char* results = NULL; unsigned char* results = NULL;
size_t bytes_read = 0; size_t bytes_read = 0;
if (!session.default_stream->read(&session, &results, &bytes_read) ) { if (!session.default_stream->read(&session, &results, &bytes_read, 5) ) {
libp2p_logger_debug("null", "stream transaction read returned false\n"); libp2p_logger_debug("null", "stream transaction read returned false\n");
break; break;
} }
if (null_shutting_down) {
break;
}
if (bytes_read == 0) { // timeout
continue;
}
libp2p_logger_debug("null", "Read %lu bytes from a stream tranaction\n", bytes_read); libp2p_logger_debug("null", "Read %lu bytes from a stream tranaction\n", bytes_read);
if (protocol_compare(results, bytes_read, "/secio")) { if (protocol_compare(results, bytes_read, "/secio")) {
libp2p_logger_debug("null", "Attempting secure io connection...\n"); libp2p_logger_debug("null", "Attempting secure io connection...\n");
@ -86,7 +93,7 @@ void *ipfs_null_connection (void *ptr)
while(_continue) { while(_continue) {
unsigned char* hash; unsigned char* hash;
size_t hash_length = 0; size_t hash_length = 0;
_continue = session.default_stream->read(&session, &hash, &hash_length); _continue = session.default_stream->read(&session, &hash, &hash_length, 5);
if (hash_length < 20) { if (hash_length < 20) {
_continue = 0; _continue = 0;
continue; continue;
@ -120,9 +127,8 @@ void *ipfs_null_connection (void *ptr)
libp2p_logger_log("null", LOGLEVEL_DEBUG, "kademlia message handled\n"); libp2p_logger_log("null", LOGLEVEL_DEBUG, "kademlia message handled\n");
} }
else { else {
libp2p_logger_error("null", "There was a problem with this connection. It is nothing I can handle. Looping to try again.\n"); libp2p_logger_error("null", "There was a problem with this connection. It is nothing I can handle. Disconnecting.\n");
// oops there was a problem break;
//TODO: Handle this
} }
free(results); free(results);
} }
@ -137,14 +143,16 @@ void *ipfs_null_connection (void *ptr)
libp2p_net_multistream_stream_free(session.insecure_stream); libp2p_net_multistream_stream_free(session.insecure_stream);
} }
(*(connection_param->count))--; // update counter. (*(connection_param->count))--; // update counter.
if (connection_param->ip != NULL)
free(connection_param->ip);
free (connection_param); free (connection_param);
return (void*) 1; return;
} }
void *ipfs_null_listen (void *ptr) void *ipfs_null_listen (void *ptr)
{ {
int socketfd, s, count = 0; int socketfd, s, count = 0;
pthread_t pth_connection; threadpool thpool = thpool_init(25);
struct IpfsNodeListenParams *listen_param; struct IpfsNodeListenParams *listen_param;
struct null_connection_params *connection_param; struct null_connection_params *connection_param;
@ -183,16 +191,13 @@ void *ipfs_null_listen (void *ptr)
connection_param->port = 0; connection_param->port = 0;
} }
// Create pthread for ipfs_null_connection. // Create pthread for ipfs_null_connection.
if (pthread_create(&pth_connection, NULL, ipfs_null_connection, connection_param)) { thpool_add_work(thpool, ipfs_null_connection, connection_param);
libp2p_logger_log("null", LOGLEVEL_DEBUG, "Error creating thread for connection %d\n", count);
close (s);
} else {
pthread_detach (pth_connection);
}
} }
} }
} }
thpool_destroy(thpool);
return (void*) 2; return (void*) 2;
} }

View file

@ -154,7 +154,7 @@ struct Node* ipfs_resolver_remote_get(const char* path, struct Node* from, const
unsigned char* response; unsigned char* response;
size_t response_size; size_t response_size;
// we should get back a protobuf'd record // we should get back a protobuf'd record
stream->read(&session_context, &response, &response_size); stream->read(&session_context, &response, &response_size, 5);
if (response_size == 1) if (response_size == 1)
return NULL; return NULL;
// turn the protobuf into a Node // turn the protobuf into a Node

View file

@ -26,7 +26,7 @@ struct IpfsNodeListenParams {
struct IpfsNode* local_node; struct IpfsNode* local_node;
}; };
void *ipfs_null_connection (void *ptr); //void *ipfs_null_connection (void *ptr);
void *ipfs_null_listen (void *ptr); void *ipfs_null_listen (void *ptr);
int ipfs_null_shutdown(); int ipfs_null_shutdown();
int ipfs_daemon (int argc, char **argv); int ipfs_daemon (int argc, char **argv);

View file

@ -0,0 +1,187 @@
/**********************************
* @author Johan Hanssen Seferidis
* License: MIT
*
**********************************/
#ifndef _THPOOL_
#define _THPOOL_
#ifdef __cplusplus
extern "C" {
#endif
/* =================================== API ======================================= */
typedef struct thpool_* threadpool;
/**
* @brief Initialize threadpool
*
* Initializes a threadpool. This function will not return untill all
* threads have initialized successfully.
*
* @example
*
* ..
* threadpool thpool; //First we declare a threadpool
* thpool = thpool_init(4); //then we initialize it to 4 threads
* ..
*
* @param num_threads number of threads to be created in the threadpool
* @return threadpool created threadpool on success,
* NULL on error
*/
threadpool thpool_init(int num_threads);
/**
* @brief Add work to the job queue
*
* Takes an action and its argument and adds it to the threadpool's job queue.
* If you want to add to work a function with more than one arguments then
* a way to implement this is by passing a pointer to a structure.
*
* NOTICE: You have to cast both the function and argument to not get warnings.
*
* @example
*
* void print_num(int num){
* printf("%d\n", num);
* }
*
* int main() {
* ..
* int a = 10;
* thpool_add_work(thpool, (void*)print_num, (void*)a);
* ..
* }
*
* @param threadpool threadpool to which the work will be added
* @param function_p pointer to function to add as work
* @param arg_p pointer to an argument
* @return 0 on successs, -1 otherwise.
*/
int thpool_add_work(threadpool, void (*function_p)(void*), void* arg_p);
/**
* @brief Wait for all queued jobs to finish
*
* Will wait for all jobs - both queued and currently running to finish.
* Once the queue is empty and all work has completed, the calling thread
* (probably the main program) will continue.
*
* Smart polling is used in wait. The polling is initially 0 - meaning that
* there is virtually no polling at all. If after 1 seconds the threads
* haven't finished, the polling interval starts growing exponentially
* untill it reaches max_secs seconds. Then it jumps down to a maximum polling
* interval assuming that heavy processing is being used in the threadpool.
*
* @example
*
* ..
* threadpool thpool = thpool_init(4);
* ..
* // Add a bunch of work
* ..
* thpool_wait(thpool);
* puts("All added work has finished");
* ..
*
* @param threadpool the threadpool to wait for
* @return nothing
*/
void thpool_wait(threadpool);
/**
* @brief Pauses all threads immediately
*
* The threads will be paused no matter if they are idle or working.
* The threads return to their previous states once thpool_resume
* is called.
*
* While the thread is being paused, new work can be added.
*
* @example
*
* threadpool thpool = thpool_init(4);
* thpool_pause(thpool);
* ..
* // Add a bunch of work
* ..
* thpool_resume(thpool); // Let the threads start their magic
*
* @param threadpool the threadpool where the threads should be paused
* @return nothing
*/
void thpool_pause(threadpool);
/**
* @brief Unpauses all threads if they are paused
*
* @example
* ..
* thpool_pause(thpool);
* sleep(10); // Delay execution 10 seconds
* thpool_resume(thpool);
* ..
*
* @param threadpool the threadpool where the threads should be unpaused
* @return nothing
*/
void thpool_resume(threadpool);
/**
* @brief Destroy the threadpool
*
* This will wait for the currently active threads to finish and then 'kill'
* the whole threadpool to free up memory.
*
* @example
* int main() {
* threadpool thpool1 = thpool_init(2);
* threadpool thpool2 = thpool_init(2);
* ..
* thpool_destroy(thpool1);
* ..
* return 0;
* }
*
* @param threadpool the threadpool to destroy
* @return nothing
*/
void thpool_destroy(threadpool);
/**
* @brief Show currently working threads
*
* Working threads are the threads that are performing work (not idle).
*
* @example
* int main() {
* threadpool thpool1 = thpool_init(2);
* threadpool thpool2 = thpool_init(2);
* ..
* printf("Working threads: %d\n", thpool_num_threads_working(thpool1));
* ..
* return 0;
* }
*
* @param threadpool the threadpool of interest
* @return integer number of threads working
*/
int thpool_num_threads_working(threadpool);
#ifdef __cplusplus
}
#endif
#endif

View file

@ -28,7 +28,8 @@ OBJS = main.o \
../unixfs/unixfs.o \ ../unixfs/unixfs.o \
../../c-protobuf/protobuf.o ../../c-protobuf/varint.o \ ../../c-protobuf/protobuf.o ../../c-protobuf/varint.o \
../util/errs.o \ ../util/errs.o \
../util/time.o ../util/time.o \
../util/thread_pool.o
%.o: %.c $(DEPS) %.o: %.c $(DEPS)
$(CC) -c -o $@ $< $(CFLAGS) $(CC) -c -o $@ $< $(CFLAGS)

View file

@ -37,7 +37,7 @@ struct Libp2pMessage* ipfs_routing_online_send_receive_message(struct Stream* st
// send the message, and expect the same back // send the message, and expect the same back
session_context.default_stream->write(&session_context, protobuf, protobuf_size); session_context.default_stream->write(&session_context, protobuf, protobuf_size);
session_context.default_stream->read(&session_context, &results, &results_size); session_context.default_stream->read(&session_context, &results, &results_size, 5);
// see if we can unprotobuf // see if we can unprotobuf
if (!libp2p_message_protobuf_decode(results, results_size, &return_message)) if (!libp2p_message_protobuf_decode(results, results_size, &return_message))
@ -190,7 +190,8 @@ int ipfs_routing_online_find_peer(struct IpfsRouting* routing, const char* peer_
int ipfs_routing_online_provide(struct IpfsRouting* routing, char* key, size_t key_size) { int ipfs_routing_online_provide(struct IpfsRouting* routing, char* key, size_t key_size) {
struct Libp2pPeer* local_peer = libp2p_peer_new(); struct Libp2pPeer* local_peer = libp2p_peer_new();
local_peer->id_size = strlen(routing->local_node->identity->peer_id); local_peer->id_size = strlen(routing->local_node->identity->peer_id);
local_peer->id = routing->local_node->identity->peer_id; local_peer->id = malloc(local_peer->id_size);
memcpy(local_peer->id, routing->local_node->identity->peer_id, local_peer->id_size);
local_peer->connection_type = CONNECTION_TYPE_CONNECTED; local_peer->connection_type = CONNECTION_TYPE_CONNECTED;
local_peer->addr_head = libp2p_utils_linked_list_new(); local_peer->addr_head = libp2p_utils_linked_list_new();
struct MultiAddress* temp_ma = multiaddress_new_from_string((char*)routing->local_node->repo->config->addresses->swarm_head->item); struct MultiAddress* temp_ma = multiaddress_new_from_string((char*)routing->local_node->repo->config->addresses->swarm_head->item);

View file

@ -28,6 +28,7 @@ OBJS = testit.o test_helper.o \
../routing/supernode.o \ ../routing/supernode.o \
../thirdparty/ipfsaddr/ipfs_addr.o \ ../thirdparty/ipfsaddr/ipfs_addr.o \
../unixfs/unixfs.o \ ../unixfs/unixfs.o \
../util/thread_pool.o \
../../c-protobuf/protobuf.o ../../c-protobuf/varint.o ../../c-protobuf/protobuf.o ../../c-protobuf/varint.o
%.o: %.c $(DEPS) %.o: %.c $(DEPS)

View file

@ -233,6 +233,90 @@ int test_routing_find_providers() {
if (local_node.routing != NULL) { if (local_node.routing != NULL) {
ipfs_routing_online_free(local_node.routing); ipfs_routing_online_free(local_node.routing);
} }
if (node != NULL)
ipfs_node_free(node);
if (result != NULL) {
// we have a vector of peers. Clean 'em up:
for(int i = 0; i < result->total; i++) {
struct Libp2pPeer* p = (struct Libp2pPeer*)libp2p_utils_vector_get(result, i);
libp2p_peer_free(p);
}
libp2p_utils_vector_free(result);
}
libp2p_logger_free();
return retVal;
}
/***
* Fire up a "client" and "server" and let the client tell the server he's providing a file
*/
int test_routing_provide() {
int retVal = 0;
// clean out repository
char* ipfs_path = "/tmp/test1";
os_utils_setenv("IPFS_PATH", ipfs_path, 1);
char* peer_id_1 = NULL;
char* peer_id_2 = NULL;
struct FSRepo* fs_repo_2 = NULL;
pthread_t thread1, thread2;
int thread1_started = 0, thread2_started = 0;
struct MultiAddress* ma_peer1 = NULL;
struct Libp2pVector* ma_vector2 = NULL;
// create peer 1
drop_and_build_repository(ipfs_path, 4001, NULL, &peer_id_1);
char multiaddress_string[255];
sprintf(multiaddress_string, "/ip4/127.0.0.1/tcp/4001/ipfs/%s", peer_id_1);
ma_peer1 = multiaddress_new_from_string(multiaddress_string);
// start the daemon in a separate thread
if (pthread_create(&thread1, NULL, test_routing_daemon_start, (void*)ipfs_path) < 0) {
fprintf(stderr, "Unable to start thread 1\n");
goto exit;
}
thread1_started = 1;
// create peer 2
ipfs_path = "/tmp/test2";
os_utils_setenv("IPFS_PATH", ipfs_path, 1);
// create a vector to hold peer1's multiaddress so we can connect as a peer
ma_vector2 = libp2p_utils_vector_new(1);
libp2p_utils_vector_add(ma_vector2, ma_peer1);
// note: this distroys some things, as it frees the fs_repo:
drop_and_build_repository(ipfs_path, 4002, ma_vector2, &peer_id_2);
// add a file, to prime the connection to peer 1
//TODO: Find a better way to do this...
size_t bytes_written = 0;
ipfs_repo_fsrepo_new(ipfs_path, NULL, &fs_repo_2);
ipfs_repo_fsrepo_open(fs_repo_2);
struct Node* node = NULL;
ipfs_import_file(NULL, "/home/parallels/ipfstest/hello_world.txt", &node, fs_repo_2, &bytes_written, 0);
ipfs_repo_fsrepo_free(fs_repo_2);
// start the daemon in a separate thread
if (pthread_create(&thread2, NULL, test_routing_daemon_start, (void*)ipfs_path) < 0) {
fprintf(stderr, "Unable to start thread 2\n");
goto exit;
}
thread2_started = 1;
// wait for everything to start up
// JMJ debugging =
sleep(3);
retVal = 1;
exit:
ipfs_daemon_stop();
if (peer_id_1 != NULL)
free(peer_id_1);
if (peer_id_2 != NULL)
free(peer_id_2);
if (thread1_started)
pthread_join(thread1, NULL);
if (thread2_started)
pthread_join(thread2, NULL);
if (ma_vector2 != NULL) {
libp2p_utils_vector_free(ma_vector2);
}
if (node != NULL) if (node != NULL)
ipfs_node_free(node); ipfs_node_free(node);
libp2p_logger_free(); libp2p_logger_free();

View file

@ -64,6 +64,7 @@ const char* names[] = {
"test_resolver_get", "test_resolver_get",
"test_routing_find_peer", "test_routing_find_peer",
"test_routing_find_providers", "test_routing_find_providers",
"test_routing_provide",
"test_routing_supernode_get_value", "test_routing_supernode_get_value",
"test_routing_supernode_get_remote_value", "test_routing_supernode_get_remote_value",
"test_unixfs_encode_decode", "test_unixfs_encode_decode",
@ -109,6 +110,7 @@ int (*funcs[])(void) = {
test_resolver_get, test_resolver_get,
test_routing_find_peer, test_routing_find_peer,
test_routing_find_providers, test_routing_find_providers,
test_routing_provide,
test_routing_supernode_get_value, test_routing_supernode_get_value,
test_routing_supernode_get_remote_value, test_routing_supernode_get_remote_value,
test_unixfs_encode_decode, test_unixfs_encode_decode,

View file

@ -7,7 +7,7 @@ endif
LFLAGS = LFLAGS =
DEPS = DEPS =
OBJS = errs.o time.o OBJS = errs.o time.o thread_pool.o
%.o: %.c $(DEPS) %.o: %.c $(DEPS)
$(CC) -c -o $@ $< $(CFLAGS) $(CC) -c -o $@ $< $(CFLAGS)

551
util/thread_pool.c Normal file
View file

@ -0,0 +1,551 @@
/* ********************************
* Author: Johan Hanssen Seferidis
* License: MIT
* Description: Library providing a threading pool where you can add
* work. For usage, check the thpool.h file or README.md
*
*//** @file thpool.h *//*
*
********************************/
#define _POSIX_C_SOURCE 200809L
#include <unistd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <errno.h>
#include <time.h>
#if defined(__linux__)
#include <sys/prctl.h>
#endif
#include "ipfs/util/thread_pool.h"
#ifdef THPOOL_DEBUG
#define THPOOL_DEBUG 1
#else
#define THPOOL_DEBUG 0
#endif
#if !defined(DISABLE_PRINT) || defined(THPOOL_DEBUG)
#define err(str) fprintf(stderr, str)
#else
#define err(str)
#endif
static volatile int threads_keepalive;
static volatile int threads_on_hold;
/* ========================== STRUCTURES ============================ */
/* Binary semaphore */
typedef struct bsem {
pthread_mutex_t mutex;
pthread_cond_t cond;
int v;
} bsem;
/* Job */
typedef struct job{
struct job* prev; /* pointer to previous job */
void (*function)(void* arg); /* function pointer */
void* arg; /* function's argument */
} job;
/* Job queue */
typedef struct jobqueue{
pthread_mutex_t rwmutex; /* used for queue r/w access */
job *front; /* pointer to front of queue */
job *rear; /* pointer to rear of queue */
bsem *has_jobs; /* flag as binary semaphore */
int len; /* number of jobs in queue */
} jobqueue;
/* Thread */
typedef struct thread{
int id; /* friendly id */
pthread_t pthread; /* pointer to actual thread */
struct thpool_* thpool_p; /* access to thpool */
} thread;
/* Threadpool */
typedef struct thpool_{
thread** threads; /* pointer to threads */
volatile int num_threads_alive; /* threads currently alive */
volatile int num_threads_working; /* threads currently working */
pthread_mutex_t thcount_lock; /* used for thread count etc */
pthread_cond_t threads_all_idle; /* signal to thpool_wait */
jobqueue jobqueue; /* job queue */
} thpool_;
/* ========================== PROTOTYPES ============================ */
static int thread_init(thpool_* thpool_p, struct thread** thread_p, int id);
static void* thread_do(struct thread* thread_p);
static void thread_hold(int sig_id);
static void thread_destroy(struct thread* thread_p);
static int jobqueue_init(jobqueue* jobqueue_p);
static void jobqueue_clear(jobqueue* jobqueue_p);
static void jobqueue_push(jobqueue* jobqueue_p, struct job* newjob_p);
static struct job* jobqueue_pull(jobqueue* jobqueue_p);
static void jobqueue_destroy(jobqueue* jobqueue_p);
static void bsem_init(struct bsem *bsem_p, int value);
static void bsem_reset(struct bsem *bsem_p);
static void bsem_post(struct bsem *bsem_p);
static void bsem_post_all(struct bsem *bsem_p);
static void bsem_wait(struct bsem *bsem_p);
/* ========================== THREADPOOL ============================ */
/* Initialise thread pool */
struct thpool_* thpool_init(int num_threads){
threads_on_hold = 0;
threads_keepalive = 1;
if (num_threads < 0){
num_threads = 0;
}
/* Make new thread pool */
thpool_* thpool_p;
thpool_p = (struct thpool_*)malloc(sizeof(struct thpool_));
if (thpool_p == NULL){
err("thpool_init(): Could not allocate memory for thread pool\n");
return NULL;
}
thpool_p->num_threads_alive = 0;
thpool_p->num_threads_working = 0;
/* Initialise the job queue */
if (jobqueue_init(&thpool_p->jobqueue) == -1){
err("thpool_init(): Could not allocate memory for job queue\n");
free(thpool_p);
return NULL;
}
/* Make threads in pool */
thpool_p->threads = (struct thread**)malloc(num_threads * sizeof(struct thread *));
if (thpool_p->threads == NULL){
err("thpool_init(): Could not allocate memory for threads\n");
jobqueue_destroy(&thpool_p->jobqueue);
free(thpool_p);
return NULL;
}
pthread_mutex_init(&(thpool_p->thcount_lock), NULL);
pthread_cond_init(&thpool_p->threads_all_idle, NULL);
/* Thread init */
int n;
for (n=0; n<num_threads; n++){
thread_init(thpool_p, &thpool_p->threads[n], n);
#if THPOOL_DEBUG
printf("THPOOL_DEBUG: Created thread %d in pool \n", n);
#endif
}
/* Wait for threads to initialize */
while (thpool_p->num_threads_alive != num_threads) {}
return thpool_p;
}
/* Add work to the thread pool */
int thpool_add_work(thpool_* thpool_p, void (*function_p)(void*), void* arg_p){
job* newjob;
newjob=(struct job*)malloc(sizeof(struct job));
if (newjob==NULL){
err("thpool_add_work(): Could not allocate memory for new job\n");
return -1;
}
/* add function and argument */
newjob->function=function_p;
newjob->arg=arg_p;
/* add job to queue */
jobqueue_push(&thpool_p->jobqueue, newjob);
return 0;
}
/* Wait until all jobs have finished */
void thpool_wait(thpool_* thpool_p){
pthread_mutex_lock(&thpool_p->thcount_lock);
while (thpool_p->jobqueue.len || thpool_p->num_threads_working) {
pthread_cond_wait(&thpool_p->threads_all_idle, &thpool_p->thcount_lock);
}
pthread_mutex_unlock(&thpool_p->thcount_lock);
}
/* Destroy the threadpool */
void thpool_destroy(thpool_* thpool_p){
/* No need to destory if it's NULL */
if (thpool_p == NULL) return ;
volatile int threads_total = thpool_p->num_threads_alive;
/* End each thread 's infinite loop */
threads_keepalive = 0;
/* Give one second to kill idle threads */
double TIMEOUT = 1.0;
time_t start, end;
double tpassed = 0.0;
time (&start);
while (tpassed < TIMEOUT && thpool_p->num_threads_alive){
bsem_post_all(thpool_p->jobqueue.has_jobs);
time (&end);
tpassed = difftime(end,start);
}
/* Poll remaining threads */
while (thpool_p->num_threads_alive){
bsem_post_all(thpool_p->jobqueue.has_jobs);
sleep(1);
}
/* Job queue cleanup */
jobqueue_destroy(&thpool_p->jobqueue);
/* Deallocs */
int n;
for (n=0; n < threads_total; n++){
thread_destroy(thpool_p->threads[n]);
}
free(thpool_p->threads);
free(thpool_p);
}
/* Pause all threads in threadpool */
void thpool_pause(thpool_* thpool_p) {
int n;
for (n=0; n < thpool_p->num_threads_alive; n++){
pthread_kill(thpool_p->threads[n]->pthread, SIGUSR1);
}
}
/* Resume all threads in threadpool */
void thpool_resume(thpool_* thpool_p) {
// resuming a single threadpool hasn't been
// implemented yet, meanwhile this supresses
// the warnings
(void)thpool_p;
threads_on_hold = 0;
}
int thpool_num_threads_working(thpool_* thpool_p){
return thpool_p->num_threads_working;
}
/* ============================ THREAD ============================== */
/* Initialize a thread in the thread pool
*
* @param thread address to the pointer of the thread to be created
* @param id id to be given to the thread
* @return 0 on success, -1 otherwise.
*/
static int thread_init (thpool_* thpool_p, struct thread** thread_p, int id){
*thread_p = (struct thread*)malloc(sizeof(struct thread));
if (thread_p == NULL){
err("thread_init(): Could not allocate memory for thread\n");
return -1;
}
(*thread_p)->thpool_p = thpool_p;
(*thread_p)->id = id;
pthread_create(&(*thread_p)->pthread, NULL, (void *)thread_do, (*thread_p));
pthread_detach((*thread_p)->pthread);
return 0;
}
/* Sets the calling thread on hold */
static void thread_hold(int sig_id) {
(void)sig_id;
threads_on_hold = 1;
while (threads_on_hold){
sleep(1);
}
}
/* What each thread is doing
*
* In principle this is an endless loop. The only time this loop gets interuppted is once
* thpool_destroy() is invoked or the program exits.
*
* @param thread thread that will run this function
* @return nothing
*/
static void* thread_do(struct thread* thread_p){
/* Set thread name for profiling and debuging */
char thread_name[128] = {0};
sprintf(thread_name, "thread-pool-%d", thread_p->id);
#if defined(__linux__)
/* Use prctl instead to prevent using _GNU_SOURCE flag and implicit declaration */
prctl(PR_SET_NAME, thread_name);
#elif defined(__APPLE__) && defined(__MACH__)
pthread_setname_np(thread_name);
#else
err("thread_do(): pthread_setname_np is not supported on this system");
#endif
/* Assure all threads have been created before starting serving */
thpool_* thpool_p = thread_p->thpool_p;
/* Register signal handler */
struct sigaction act;
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
act.sa_handler = thread_hold;
if (sigaction(SIGUSR1, &act, NULL) == -1) {
err("thread_do(): cannot handle SIGUSR1");
}
/* Mark thread as alive (initialized) */
pthread_mutex_lock(&thpool_p->thcount_lock);
thpool_p->num_threads_alive += 1;
pthread_mutex_unlock(&thpool_p->thcount_lock);
while(threads_keepalive){
bsem_wait(thpool_p->jobqueue.has_jobs);
if (threads_keepalive){
pthread_mutex_lock(&thpool_p->thcount_lock);
thpool_p->num_threads_working++;
pthread_mutex_unlock(&thpool_p->thcount_lock);
/* Read job from queue and execute it */
void (*func_buff)(void*);
void* arg_buff;
job* job_p = jobqueue_pull(&thpool_p->jobqueue);
if (job_p) {
func_buff = job_p->function;
arg_buff = job_p->arg;
func_buff(arg_buff);
free(job_p);
}
pthread_mutex_lock(&thpool_p->thcount_lock);
thpool_p->num_threads_working--;
if (!thpool_p->num_threads_working) {
pthread_cond_signal(&thpool_p->threads_all_idle);
}
pthread_mutex_unlock(&thpool_p->thcount_lock);
}
}
pthread_mutex_lock(&thpool_p->thcount_lock);
thpool_p->num_threads_alive --;
pthread_mutex_unlock(&thpool_p->thcount_lock);
return NULL;
}
/* Frees a thread */
static void thread_destroy (thread* thread_p){
free(thread_p);
}
/* ============================ JOB QUEUE =========================== */
/* Initialize queue */
static int jobqueue_init(jobqueue* jobqueue_p){
jobqueue_p->len = 0;
jobqueue_p->front = NULL;
jobqueue_p->rear = NULL;
jobqueue_p->has_jobs = (struct bsem*)malloc(sizeof(struct bsem));
if (jobqueue_p->has_jobs == NULL){
return -1;
}
pthread_mutex_init(&(jobqueue_p->rwmutex), NULL);
bsem_init(jobqueue_p->has_jobs, 0);
return 0;
}
/* Clear the queue */
static void jobqueue_clear(jobqueue* jobqueue_p){
while(jobqueue_p->len){
free(jobqueue_pull(jobqueue_p));
}
jobqueue_p->front = NULL;
jobqueue_p->rear = NULL;
bsem_reset(jobqueue_p->has_jobs);
jobqueue_p->len = 0;
}
/* Add (allocated) job to queue
*/
static void jobqueue_push(jobqueue* jobqueue_p, struct job* newjob){
pthread_mutex_lock(&jobqueue_p->rwmutex);
newjob->prev = NULL;
switch(jobqueue_p->len){
case 0: /* if no jobs in queue */
jobqueue_p->front = newjob;
jobqueue_p->rear = newjob;
break;
default: /* if jobs in queue */
jobqueue_p->rear->prev = newjob;
jobqueue_p->rear = newjob;
}
jobqueue_p->len++;
bsem_post(jobqueue_p->has_jobs);
pthread_mutex_unlock(&jobqueue_p->rwmutex);
}
/* Get first job from queue(removes it from queue)
<<<<<<< HEAD
*
* Notice: Caller MUST hold a mutex
=======
>>>>>>> da2c0fe45e43ce0937f272c8cd2704bdc0afb490
*/
static struct job* jobqueue_pull(jobqueue* jobqueue_p){
pthread_mutex_lock(&jobqueue_p->rwmutex);
job* job_p = jobqueue_p->front;
switch(jobqueue_p->len){
case 0: /* if no jobs in queue */
break;
case 1: /* if one job in queue */
jobqueue_p->front = NULL;
jobqueue_p->rear = NULL;
jobqueue_p->len = 0;
break;
default: /* if >1 jobs in queue */
jobqueue_p->front = job_p->prev;
jobqueue_p->len--;
/* more than one job in queue -> post it */
bsem_post(jobqueue_p->has_jobs);
}
pthread_mutex_unlock(&jobqueue_p->rwmutex);
return job_p;
}
/* Free all queue resources back to the system */
static void jobqueue_destroy(jobqueue* jobqueue_p){
jobqueue_clear(jobqueue_p);
free(jobqueue_p->has_jobs);
}
/* ======================== SYNCHRONISATION ========================= */
/* Init semaphore to 1 or 0 */
static void bsem_init(bsem *bsem_p, int value) {
if (value < 0 || value > 1) {
err("bsem_init(): Binary semaphore can take only values 1 or 0");
exit(1);
}
pthread_mutex_init(&(bsem_p->mutex), NULL);
pthread_cond_init(&(bsem_p->cond), NULL);
bsem_p->v = value;
}
/* Reset semaphore to 0 */
static void bsem_reset(bsem *bsem_p) {
bsem_init(bsem_p, 0);
}
/* Post to at least one thread */
static void bsem_post(bsem *bsem_p) {
pthread_mutex_lock(&bsem_p->mutex);
bsem_p->v = 1;
pthread_cond_signal(&bsem_p->cond);
pthread_mutex_unlock(&bsem_p->mutex);
}
/* Post to all threads */
static void bsem_post_all(bsem *bsem_p) {
pthread_mutex_lock(&bsem_p->mutex);
bsem_p->v = 1;
pthread_cond_broadcast(&bsem_p->cond);
pthread_mutex_unlock(&bsem_p->mutex);
}
/* Wait on semaphore until semaphore has value 0 */
static void bsem_wait(bsem* bsem_p) {
pthread_mutex_lock(&bsem_p->mutex);
while (bsem_p->v != 1) {
pthread_cond_wait(&bsem_p->cond, &bsem_p->mutex);
}
bsem_p->v = 0;
pthread_mutex_unlock(&bsem_p->mutex);
}