From: Michael Tremer <michael.tremer@ipfire.org>
Date: Thu, 19 Sep 2024 07:50:56 +0000 (+0000)
Subject: server: Use the new worker
X-Git-Url: http://git.ipfire.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=edd32873afd625e3b6997105a21df3c8905e8458;p=fireperf.git

server: Use the new worker

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/server.c b/src/server.c
index 85316dd..c9d6c1c 100644
--- a/src/server.c
+++ b/src/server.c
@@ -20,7 +20,6 @@
 
 #include <errno.h>
 #include <netinet/tcp.h>
-#include <pthread.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -32,262 +31,51 @@
 #include "main.h"
 #include "server.h"
 #include "util.h"
+#include "worker.h"
 
 #define MAX_WORKERS       128
 #define SOCKET_BACKLOG   1024
 
-struct fireperf_worker {
-	// Thread
-	pthread_t thread;
-
-	// Configuration
-	struct fireperf_config* conf;
-
-	// Collect stats
-	struct fireperf_stats stats;
-
-	// Client Socket
-	int client;
-
-	// Epoll
-	int epollfd;
-
-	// Return code
-	int r;
-};
-
 struct fireperf_server {
 	// Configuration
 	struct fireperf_config* conf;
 
-	// Collect stats
-	struct fireperf_stats stats;
+	// Count all connections
+	unsigned int connections;
 
 	// Workers
 	struct fireperf_worker* workers[MAX_WORKERS];
 	unsigned int num_workers;
 };
 
-static int is_worker_alive(struct fireperf_worker* worker) {
-	return pthread_tryjoin_np(worker->thread, NULL);
-}
-
-static int join_worker(struct fireperf_worker* worker) {
-	int r;
-
-	// Join the worker
-	r = pthread_join(worker->thread, NULL);
-	if (r) {
-		ERROR(worker->conf, "Could not join worker: %s\n", strerror(errno));
-		return -errno;
-	}
-
-	return 0;
-}
+static struct fireperf_stats get_stats(struct fireperf_server* server) {
+	const struct fireperf_stats* s = NULL;
 
-static void free_worker(struct fireperf_worker* worker) {
-	free(worker);
-}
-
-static int free_terminated_workers(struct fireperf_server* server) {
-	int r;
-
-	for (unsigned int i = 0; i < MAX_WORKERS; i++) {
-		struct fireperf_worker* worker = server->workers[i];
-
-		// Skip any empty slots
-		if (!worker)
-			continue;
-
-		// Skip any workers that are still alive
-		if (is_worker_alive(worker))
-			continue;
-
-		// Free worker
-		free_worker(worker);
-
-		// Clear the slot
-		server->workers[i] = NULL;
-	}
-}
-
-static void* run_worker(void* w) {
-	struct fireperf_worker* worker = w;
-	int ready;
-	int fd = -1;
-	int r;
-
-	struct epoll_event events[EPOLL_MAX_EVENTS];
-
-	DEBUG(worker->conf, "New worker launched as %lu...\n", pthread_self());
-
-	// We have exactly one open connection
-	worker->stats.open_connections = 1;
-
-	worker->epollfd = -1;
-
-	// Initialize epoll()
-	worker->epollfd = epoll_create1(0);
-	if (worker->epollfd < 0) {
-		ERROR(worker->conf, "Could not initialize epoll(): %s\n", strerror(errno));
-		r = -errno;
-		goto ERROR;
-	}
-
-	struct epoll_event ev = {
-		.events  = EPOLLIN|EPOLLRDHUP,
-		.data.fd = worker->client,
+	struct fireperf_stats stats = {
+		.connections = server->connections,
 	};
 
-	if (!worker->conf->keepalive_only)
-		ev.events |= EPOLLOUT;
-
-	// Add the socket to the loop
-	r = epoll_ctl(worker->epollfd, EPOLL_CTL_ADD, worker->client, &ev);
-	if (r) {
-		ERROR(worker->conf, "Could not add the socket to epoll(): %s\n", strerror(errno));
-		r = -errno;
-		goto ERROR;
-	}
-
-	// Enter the main loop...
-	for (;;) {
-		ready = epoll_wait(worker->epollfd, events, EPOLL_MAX_EVENTS, -1);
-		if (ready < 1) {
-			// We terminate gracefully when we receive a signal
-			if (errno == EINTR)
-				break;
-
-			ERROR(worker->conf, "epoll_wait() failed: %s\n", strerror(errno));
-			r = -errno;
-			goto ERROR;
-		}
-
-		// Loop through all sockets that are ready...
-		for (int i = 0; i < ready; i++) {
-			fd = events[i].data.fd;
-
-			// Handle the client socket
-			if (worker->client == fd) {
-				if (events[i].events & EPOLLRDHUP) {
-					DEBUG(worker->conf, "Connection %d has closed\n", fd);
-
-					// There is no point in continuing any further
-					// after the client went away
-					goto ERROR;
-				}
-
-				// Handle incoming data
-				if (events[i].events & EPOLLIN) {
-					r = handle_connection_recv(worker->conf, &worker->stats, fd);
-					if (r < 0)
-						goto ERROR;
-				}
-
-				// Handle outgoing data
-				if (events[i].events & EPOLLOUT) {
-					r = handle_connection_send(worker->conf, &worker->stats, fd);
-					if (r < 0)
-						goto ERROR;
-				}
-			}
-		}
-	}
-
-ERROR:
-	if (worker->epollfd >= 0)
-		close(worker->epollfd);
-	if (worker->client >= 0)
-		close(worker->client);
-
-	// Store the return code
-	worker->r = r;
-
-	return &worker->r;
-}
-
-static int create_worker(struct fireperf_server* server, const int fd) {
-	struct fireperf_worker* worker = NULL;
-	int r;
-
-	DEBUG(server->conf, "Creating a new worker for %d\n", fd);
-
-	// Check if we have space for a new worker
-	if (server->num_workers >= MAX_WORKERS) {
-		ERROR(server->conf, "Maximum number of workers reached. Closing connection.\n");
-		return -ENOSPC;
-	}
-
-	// Allocate a new worker
-	worker = calloc(1, sizeof(*worker));
-	if (!worker)
-		return -errno;
-
-	// Store a reference to the configuration
-	worker->conf = server->conf;
-
-	// Store the client socket
-	worker->client = fd;
-
-	// Store the worker
+	// Add up everything from all workers
 	for (unsigned int i = 0; i < MAX_WORKERS; i++) {
-		if (server->workers[i])
+		if (!server->workers[i])
 			continue;
 
-		// Store a reference in the first free slot
-		server->workers[i] = worker;
-		break;
-	}
-
-	// We now have more workers
-	++server->num_workers;
-
-	// Run the worker
-	r = pthread_create(&worker->thread, NULL, run_worker, worker);
-	if (r) {
-		ERROR(server->conf, "Could not launch thread: %s\n", strerror(r));
-		return -r;
-	}
-
-	return 0;
-}
-
-static int cumulate_stats(struct fireperf_stats* stats, struct fireperf_server* server) {
-	struct fireperf_worker* worker = NULL;
-
-	// Reset open connections
-	stats->open_connections = 0;
-
-	// Fetch the total number of connections
-	stats->connections = server->stats.connections;
-
-	// Reset what has been sent in the last period
-	stats->bytes_received       = 0;
-	stats->bytes_sent           = 0;
-
-	// Reset the stats to the server's stats
-	stats->total_bytes_received = server->stats.total_bytes_received;
-	stats->total_bytes_sent     = server->stats.total_bytes_sent;
-
-	// Add up all the worker's stats
-	for (unsigned int i = 0; i < MAX_WORKERS; i++) {
-		worker = server->workers[i];
-		if (!worker)
+		// Fetch stats
+		s = fireperf_worker_get_stats(server->workers[i]);
+		if (!s)
 			continue;
 
-		stats->open_connections     += worker->stats.open_connections;
+		// Sum up all open connections
+		stats.open_connections += s->open_connections;
 
-		stats->bytes_received       += worker->stats.bytes_received;
-		stats->total_bytes_received += worker->stats.total_bytes_received;
-		stats->bytes_sent           += worker->stats.bytes_sent;
-		stats->total_bytes_sent     += worker->stats.total_bytes_sent;
-
-		// Reset
-		worker->stats.bytes_received = 0;
-		worker->stats.bytes_sent     = 0;
+		// Sum up the transferred data
+		stats.bytes_received       += s->bytes_received;
+		stats.total_bytes_received += s->total_bytes_received;
+		stats.bytes_sent           += s->bytes_sent;
+		stats.total_bytes_sent     += s->total_bytes_sent;
 	}
 
-	return 0;
+	return stats;
 }
 
 static int enable_keepalive(struct fireperf_config* conf, int fd) {
@@ -407,7 +195,50 @@ ERROR:
 	return -1;
 }
 
+/*
+	This function selects the worker that is used for the an incoming connection
+*/
+static struct fireperf_worker* fetch_worker(struct fireperf_server* server) {
+	struct fireperf_worker* worker = NULL;
+	int r;
+
+	/*
+		XXX TODO
+		To keep things simple, we create a new worker for each call.
+
+		This should be replaced by a method that searches for the worker with
+		the least amount of connections and start up to as many workers as we
+		have CPU cores.
+	*/
+
+	// Create a new worker
+	r = fireperf_worker_create(&worker, server->conf);
+	if (r < 0) {
+		ERROR(server->conf, "Could not create worker: %s\n", strerror(-r));
+		goto ERROR;
+	}
+
+	// Launch the worker
+	r = fireperf_worker_launch(worker);
+	if (r < 0) {
+		ERROR(server->conf, "Could not launch worker: %s\n", strerror(-r));
+		goto ERROR;
+	}
+
+	// Store a reference
+	server->workers[server->num_workers++] = worker;
+
+	return worker;
+
+ERROR:
+	if (worker)
+		fireperf_worker_free(worker);
+
+	return NULL;
+}
+
 static int accept_connection(struct fireperf_server* server, int sockfd) {
+	struct fireperf_worker* worker = NULL;
 	struct sockaddr_in6 addr = {};
 	int r;
 
@@ -428,29 +259,40 @@ static int accept_connection(struct fireperf_server* server, int sockfd) {
 	DEBUG(server->conf, "New connection accepted on socket %d\n", fd);
 
 	// A connection has been opened
-	server->stats.open_connections++;
-	server->stats.connections++;
+	server->connections++;
 
 	// Close connections immediately when -x is set
 	if (server->conf->close) {
-		DEBUG(server->conf, "Closing connection %d\n", fd);
 		r = 0;
 
 		goto ERROR;
 	}
 
-	// Create a new worker
-	r = create_worker(server, fd);
+	// Find a worker to delegate this connection to
+	worker = fetch_worker(server);
+
+	// Close the connection if we could not find a worker
+	if (!worker) {
+		ERROR(server->conf, "Could not find a worker that could handle a new connection\n");
+		r = -EBUSY;
+		goto ERROR;
+	}
+
+	// Delegate the connection
+	r = fireperf_worker_delegate(worker, fd);
 	if (r < 0) {
-		ERROR(server->conf, "Could not create worker: %s\n", strerror(-r));
+		ERROR(server->conf, "Could not delegate a new connection to a worker: %s\n", strerror(-r));
 		goto ERROR;
 	}
 
-	return fd;
+	return 0;
 
 ERROR:
-	if (fd >= 0)
+	if (fd >= 0) {
+		DEBUG(server->conf, "Closing connection %d\n", fd);
+
 		close(fd);
+	}
 
 	return r;
 }
@@ -529,15 +371,8 @@ int fireperf_server(struct fireperf_config* conf, int epollfd, int timerfd) {
 					goto ERROR;
 				}
 
-				// Free any terminated workers
-				r = free_terminated_workers(&server);
-				if (r)
-					goto ERROR;
-
 				// Cumulate stats
-				r = cumulate_stats(&stats, &server);
-				if (r)
-					goto ERROR;
+				stats = get_stats(&server);
 
 				// Print the stats
 				r = fireperf_dump_stats(conf, &stats, FIREPERF_MODE_SERVER);
@@ -553,18 +388,5 @@ ERROR:
 			close(listening_sockets[i]);
 	}
 
-	// Wait for all workers to terminate
-	for (unsigned int i = 0; i < MAX_WORKERS; i++) {
-		if (server.workers[i]) {
-			// Wait for the worker to terminate
-			join_worker(server.workers[i]);
-
-			// Free the worker
-			free_worker(server.workers[i]);
-
-			server.workers[i] = NULL;
-		}
-	}
-
 	return r;
 }
diff --git a/src/worker.c b/src/worker.c
index 2eef429..b51216a 100644
--- a/src/worker.c
+++ b/src/worker.c
@@ -34,16 +34,15 @@ struct fireperf_worker {
 	// Configuration
 	struct fireperf_config* conf;
 
+	// Collect stats
+	struct fireperf_stats stats;
+
 	// Epoll
 	int epollfd;
-};
-
-static void fireperf_worker_free(struct fireperf_worker* worker) {
-	if (worker->epollfd >= 0)
-		close(worker->epollfd);
 
-	free(worker);
-}
+	// Exit Code
+	int r;
+};
 
 int fireperf_worker_create(struct fireperf_worker** worker, struct fireperf_config* conf) {
 	struct fireperf_worker* w = NULL;
@@ -79,15 +78,87 @@ ERROR:
 	return r;
 }
 
+void fireperf_worker_free(struct fireperf_worker* worker) {
+	if (worker->epollfd >= 0)
+		close(worker->epollfd);
+
+	free(worker);
+}
+
 /*
 	The main function of the worker.
 */
 static void* fireperf_worker_main(void* w) {
 	struct fireperf_worker* worker = w;
+	int ready = 0;
+	int r;
 
 	DEBUG(worker->conf, "New worker launched as %lu\n", pthread_self());
 
-	return 0;
+	struct epoll_event events[EPOLL_MAX_EVENTS];
+
+	// Enter the main loop...
+	for (;;) {
+		ready = epoll_wait(worker->epollfd, events, EPOLL_MAX_EVENTS, -1);
+		if (ready < 1) {
+			// We terminate gracefully when we receive a signal
+			if (errno == EINTR)
+				break;
+
+			ERROR(worker->conf, "epoll_wait() failed: %m\n");
+			r = -errno;
+			goto ERROR;
+		}
+
+		// Loop through all sockets that are ready...
+		for (int i = 0; i < ready; i++) {
+			int fd = events[i].data.fd;
+
+			// Handle closed connections
+			if (events[i].events & EPOLLRDHUP) {
+				DEBUG(worker->conf, "Connection %d has closed\n", fd);
+
+				// We now have one fewer connections
+				worker->stats.open_connections--;
+
+				// Remove the file descriptor from epoll()
+				r = epoll_ctl(worker->epollfd, EPOLL_CTL_DEL, fd, NULL);
+				if (r) {
+					ERROR(worker->conf, "Could not remove socket file descriptfor from epoll(): %m\n");
+					r = -errno;
+					goto ERROR;
+				}
+
+				// Free up any resources
+				close(fd);
+
+				// There is no point in continuing any further after the connection closed
+				break;
+			}
+
+			// Handle incoming data
+			if (events[i].events & EPOLLIN) {
+				r = handle_connection_recv(worker->conf, &worker->stats, fd);
+				if (r < 0)
+					goto ERROR;
+			}
+
+			// Handle outgoing data
+			if (events[i].events & EPOLLOUT) {
+				r = handle_connection_send(worker->conf, &worker->stats, fd);
+				if (r < 0)
+					goto ERROR;
+			}
+		}
+	}
+
+	DEBUG(worker->conf, "Worker has gracefully terminated\n");
+
+ERROR:
+	// Store the return code
+	worker->r = r;
+
+	return &worker->r;
 }
 
 int fireperf_worker_launch(struct fireperf_worker* worker) {
@@ -102,6 +173,41 @@ int fireperf_worker_launch(struct fireperf_worker* worker) {
 	return r;
 }
 
+int fireperf_worker_terminate(struct fireperf_worker* worker) {
+	// If the worker has terminated, we return its exit code
+	if (!fireperf_worker_is_alive(worker))
+		return worker->r;
+
+	// XXX Otherwise we need to do something else
+	return 0;
+}
+
 int fireperf_worker_is_alive(struct fireperf_worker* worker) {
 	return pthread_tryjoin_np(worker->thread, NULL);
 }
+
+int fireperf_worker_delegate(struct fireperf_worker* worker, int socket) {
+	int r;
+
+	struct epoll_event ev = {
+		.events  = EPOLLIN|EPOLLRDHUP,
+		.data.fd = socket,
+	};
+
+	if (!worker->conf->keepalive_only)
+		ev.events |= EPOLLOUT;
+
+	// Add the socket to the loop
+	r = epoll_ctl(worker->epollfd, EPOLL_CTL_ADD, socket, &ev);
+	if (r)
+		ERROR(worker->conf, "Could not add the socket to epoll(): %m\n");
+
+	// We now have one more open connections
+	worker->stats.open_connections++;
+
+	return r;
+}
+
+const struct fireperf_stats* fireperf_worker_get_stats(struct fireperf_worker* worker) {
+	return &worker->stats;
+}
diff --git a/src/worker.h b/src/worker.h
index e7d182b..fb962c6 100644
--- a/src/worker.h
+++ b/src/worker.h
@@ -26,8 +26,14 @@ struct fireperf_worker;
 #include "main.h"
 
 int fireperf_worker_create(struct fireperf_worker** worker, struct fireperf_config* conf);
+void fireperf_worker_free(struct fireperf_worker* worker);
 
 int fireperf_worker_launch(struct fireperf_worker* worker);
+int fireperf_worker_terminate(struct fireperf_worker* worker);
 int fireperf_worker_is_alive(struct fireperf_worker* worker);
 
+int fireperf_worker_delegate(struct fireperf_worker* worker, int socket);
+
+const struct fireperf_stats* fireperf_worker_get_stats(struct fireperf_worker* worker);
+
 #endif /* FIREPERF_WORKER_H */