diff options
Diffstat (limited to 'fs/dlm/lowcomms-tcp.c')
-rw-r--r-- | fs/dlm/lowcomms-tcp.c | 384 |
1 files changed, 101 insertions, 283 deletions
diff --git a/fs/dlm/lowcomms-tcp.c b/fs/dlm/lowcomms-tcp.c index 9be3a440c42..07e0a122c32 100644 --- a/fs/dlm/lowcomms-tcp.c +++ b/fs/dlm/lowcomms-tcp.c @@ -2,7 +2,7 @@ ******************************************************************************* ** ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. -** Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. +** Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved. ** ** This copyrighted material is made available to anyone wishing to use, ** modify, copy, or redistribute it subject to the terms and conditions @@ -96,10 +96,7 @@ static bool cbuf_empty(struct cbuf *cb) struct connection { struct socket *sock; /* NULL if not connected */ uint32_t nodeid; /* So we know who we are in the list */ - struct rw_semaphore sock_sem; /* Stop connect races */ - struct list_head read_list; /* On this list when ready for reading */ - struct list_head write_list; /* On this list when ready for writing */ - struct list_head state_list; /* On this list when ready to connect */ + struct mutex sock_mutex; unsigned long flags; /* bit 1,2 = We are on the read/write lists */ #define CF_READ_PENDING 1 #define CF_WRITE_PENDING 2 @@ -112,9 +109,10 @@ struct connection { struct page *rx_page; struct cbuf cb; int retries; - atomic_t waiting_requests; #define MAX_CONNECT_RETRIES 3 struct connection *othercon; + struct work_struct rwork; /* Receive workqueue */ + struct work_struct swork; /* Send workqueue */ }; #define sock2con(x) ((struct connection *)(x)->sk_user_data) @@ -131,14 +129,9 @@ struct writequeue_entry { static struct sockaddr_storage dlm_local_addr; -/* Manage daemons */ -static struct task_struct *recv_task; -static struct task_struct *send_task; - -static wait_queue_t lowcomms_send_waitq_head; -static DECLARE_WAIT_QUEUE_HEAD(lowcomms_send_waitq); -static wait_queue_t lowcomms_recv_waitq_head; -static DECLARE_WAIT_QUEUE_HEAD(lowcomms_recv_waitq); +/* Work queues */ +static struct workqueue_struct *recv_workqueue; +static struct workqueue_struct *send_workqueue; /* An array of pointers to connections, indexed by NODEID */ static struct connection **connections; @@ -146,17 +139,8 @@ static DECLARE_MUTEX(connections_lock); static struct kmem_cache *con_cache; static int conn_array_size; -/* List of sockets that have reads pending */ -static LIST_HEAD(read_sockets); -static DEFINE_SPINLOCK(read_sockets_lock); - -/* List of sockets which have writes pending */ -static LIST_HEAD(write_sockets); -static DEFINE_SPINLOCK(write_sockets_lock); - -/* List of sockets which have connects pending */ -static LIST_HEAD(state_sockets); -static DEFINE_SPINLOCK(state_sockets_lock); +static void process_recv_sockets(struct work_struct *work); +static void process_send_sockets(struct work_struct *work); static struct connection *nodeid2con(int nodeid, gfp_t allocation) { @@ -186,9 +170,11 @@ static struct connection *nodeid2con(int nodeid, gfp_t allocation) goto finish; con->nodeid = nodeid; - init_rwsem(&con->sock_sem); + mutex_init(&con->sock_mutex); INIT_LIST_HEAD(&con->writequeue); spin_lock_init(&con->writequeue_lock); + INIT_WORK(&con->swork, process_send_sockets); + INIT_WORK(&con->rwork, process_recv_sockets); connections[nodeid] = con; } @@ -203,41 +189,22 @@ static void lowcomms_data_ready(struct sock *sk, int count_unused) { struct connection *con = sock2con(sk); - atomic_inc(&con->waiting_requests); - if (test_and_set_bit(CF_READ_PENDING, &con->flags)) - return; - - spin_lock_bh(&read_sockets_lock); - list_add_tail(&con->read_list, &read_sockets); - spin_unlock_bh(&read_sockets_lock); - - wake_up_interruptible(&lowcomms_recv_waitq); + if (!test_and_set_bit(CF_READ_PENDING, &con->flags)) + queue_work(recv_workqueue, &con->rwork); } static void lowcomms_write_space(struct sock *sk) { struct connection *con = sock2con(sk); - if (test_and_set_bit(CF_WRITE_PENDING, &con->flags)) - return; - - spin_lock_bh(&write_sockets_lock); - list_add_tail(&con->write_list, &write_sockets); - spin_unlock_bh(&write_sockets_lock); - - wake_up_interruptible(&lowcomms_send_waitq); + if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) + queue_work(send_workqueue, &con->swork); } static inline void lowcomms_connect_sock(struct connection *con) { - if (test_and_set_bit(CF_CONNECT_PENDING, &con->flags)) - return; - - spin_lock_bh(&state_sockets_lock); - list_add_tail(&con->state_list, &state_sockets); - spin_unlock_bh(&state_sockets_lock); - - wake_up_interruptible(&lowcomms_send_waitq); + if (!test_and_set_bit(CF_CONNECT_PENDING, &con->flags)) + queue_work(send_workqueue, &con->swork); } static void lowcomms_state_change(struct sock *sk) @@ -279,7 +246,7 @@ static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port, /* Close a remote connection and tidy up */ static void close_connection(struct connection *con, bool and_other) { - down_write(&con->sock_sem); + mutex_lock(&con->sock_mutex); if (con->sock) { sock_release(con->sock); @@ -294,24 +261,27 @@ static void close_connection(struct connection *con, bool and_other) con->rx_page = NULL; } con->retries = 0; - up_write(&con->sock_sem); + mutex_unlock(&con->sock_mutex); } /* Data received from remote end */ static int receive_from_sock(struct connection *con) { int ret = 0; - struct msghdr msg; - struct iovec iov[2]; - mm_segment_t fs; + struct msghdr msg = {}; + struct kvec iov[2]; unsigned len; int r; int call_again_soon = 0; + int nvec; - down_read(&con->sock_sem); + mutex_lock(&con->sock_mutex); + + if (con->sock == NULL) { + ret = -EAGAIN; + goto out_close; + } - if (con->sock == NULL) - goto out; if (con->rx_page == NULL) { /* * This doesn't need to be atomic, but I think it should @@ -323,21 +293,13 @@ static int receive_from_sock(struct connection *con) cbuf_init(&con->cb, PAGE_CACHE_SIZE); } - msg.msg_control = NULL; - msg.msg_controllen = 0; - msg.msg_iovlen = 1; - msg.msg_iov = iov; - msg.msg_name = NULL; - msg.msg_namelen = 0; - msg.msg_flags = 0; - /* * iov[0] is the bit of the circular buffer between the current end * point (cb.base + cb.len) and the end of the buffer. */ iov[0].iov_len = con->cb.base - cbuf_data(&con->cb); iov[0].iov_base = page_address(con->rx_page) + cbuf_data(&con->cb); - iov[1].iov_len = 0; + nvec = 1; /* * iov[1] is the bit of the circular buffer between the start of the @@ -347,18 +309,18 @@ static int receive_from_sock(struct connection *con) iov[0].iov_len = PAGE_CACHE_SIZE - cbuf_data(&con->cb); iov[1].iov_len = con->cb.base; iov[1].iov_base = page_address(con->rx_page); - msg.msg_iovlen = 2; + nvec = 2; } len = iov[0].iov_len + iov[1].iov_len; - fs = get_fs(); - set_fs(get_ds()); - r = ret = sock_recvmsg(con->sock, &msg, len, + r = ret = kernel_recvmsg(con->sock, &msg, iov, nvec, len, MSG_DONTWAIT | MSG_NOSIGNAL); - set_fs(fs); if (ret <= 0) goto out_close; + if (ret == -EAGAIN) + goto out_resched; + if (ret == len) call_again_soon = 1; cbuf_add(&con->cb, ret); @@ -381,24 +343,26 @@ static int receive_from_sock(struct connection *con) con->rx_page = NULL; } -out: if (call_again_soon) goto out_resched; - up_read(&con->sock_sem); + mutex_unlock(&con->sock_mutex); return 0; out_resched: - lowcomms_data_ready(con->sock->sk, 0); - up_read(&con->sock_sem); - cond_resched(); - return 0; + if (!test_and_set_bit(CF_READ_PENDING, &con->flags)) + queue_work(recv_workqueue, &con->rwork); + mutex_unlock(&con->sock_mutex); + return -EAGAIN; out_close: - up_read(&con->sock_sem); + mutex_unlock(&con->sock_mutex); if (ret != -EAGAIN && !test_bit(CF_IS_OTHERCON, &con->flags)) { close_connection(con, false); /* Reconnect when there is something to send */ } + /* Don't return success if we really got EOF */ + if (ret == 0) + ret = -EAGAIN; return ret; } @@ -412,6 +376,7 @@ static int accept_from_sock(struct connection *con) int len; int nodeid; struct connection *newcon; + struct connection *addcon; memset(&peeraddr, 0, sizeof(peeraddr)); result = sock_create_kern(dlm_local_addr.ss_family, SOCK_STREAM, @@ -419,7 +384,7 @@ static int accept_from_sock(struct connection *con) if (result < 0) return -ENOMEM; - down_read(&con->sock_sem); + mutex_lock_nested(&con->sock_mutex, 0); result = -ENOTCONN; if (con->sock == NULL) @@ -445,7 +410,7 @@ static int accept_from_sock(struct connection *con) if (dlm_addr_to_nodeid(&peeraddr, &nodeid)) { printk("dlm: connect from non cluster node\n"); sock_release(newsock); - up_read(&con->sock_sem); + mutex_unlock(&con->sock_mutex); return -1; } @@ -462,7 +427,7 @@ static int accept_from_sock(struct connection *con) result = -ENOMEM; goto accept_err; } - down_write(&newcon->sock_sem); + mutex_lock_nested(&newcon->sock_mutex, 1); if (newcon->sock) { struct connection *othercon = newcon->othercon; @@ -470,41 +435,45 @@ static int accept_from_sock(struct connection *con) othercon = kmem_cache_zalloc(con_cache, GFP_KERNEL); if (!othercon) { printk("dlm: failed to allocate incoming socket\n"); - up_write(&newcon->sock_sem); + mutex_unlock(&newcon->sock_mutex); result = -ENOMEM; goto accept_err; } othercon->nodeid = nodeid; othercon->rx_action = receive_from_sock; - init_rwsem(&othercon->sock_sem); + mutex_init(&othercon->sock_mutex); + INIT_WORK(&othercon->swork, process_send_sockets); + INIT_WORK(&othercon->rwork, process_recv_sockets); set_bit(CF_IS_OTHERCON, &othercon->flags); newcon->othercon = othercon; } othercon->sock = newsock; newsock->sk->sk_user_data = othercon; add_sock(newsock, othercon); + addcon = othercon; } else { newsock->sk->sk_user_data = newcon; newcon->rx_action = receive_from_sock; add_sock(newsock, newcon); - + addcon = newcon; } - up_write(&newcon->sock_sem); + mutex_unlock(&newcon->sock_mutex); /* * Add it to the active queue in case we got data * beween processing the accept adding the socket * to the read_sockets list */ - lowcomms_data_ready(newsock->sk, 0); - up_read(&con->sock_sem); + if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags)) + queue_work(recv_workqueue, &addcon->rwork); + mutex_unlock(&con->sock_mutex); return 0; accept_err: - up_read(&con->sock_sem); + mutex_unlock(&con->sock_mutex); sock_release(newsock); if (result != -EAGAIN) @@ -525,7 +494,7 @@ static void connect_to_sock(struct connection *con) return; } - down_write(&con->sock_sem); + mutex_lock(&con->sock_mutex); if (con->retries++ > MAX_CONNECT_RETRIES) goto out; @@ -548,7 +517,7 @@ static void connect_to_sock(struct connection *con) sock->sk->sk_user_data = con; con->rx_action = receive_from_sock; - make_sockaddr(&saddr, dlm_config.tcp_port, &addr_len); + make_sockaddr(&saddr, dlm_config.ci_tcp_port, &addr_len); add_sock(sock, con); @@ -577,7 +546,7 @@ out_err: result = 0; } out: - up_write(&con->sock_sem); + mutex_unlock(&con->sock_mutex); return; } @@ -616,10 +585,10 @@ static struct socket *create_listen_sock(struct connection *con, con->sock = sock; /* Bind to our port */ - make_sockaddr(saddr, dlm_config.tcp_port, &addr_len); + make_sockaddr(saddr, dlm_config.ci_tcp_port, &addr_len); result = sock->ops->bind(sock, (struct sockaddr *) saddr, addr_len); if (result < 0) { - printk("dlm: Can't bind to port %d\n", dlm_config.tcp_port); + printk("dlm: Can't bind to port %d\n", dlm_config.ci_tcp_port); sock_release(sock); sock = NULL; con->sock = NULL; @@ -638,7 +607,7 @@ static struct socket *create_listen_sock(struct connection *con, result = sock->ops->listen(sock, 5); if (result < 0) { - printk("dlm: Can't listen on port %d\n", dlm_config.tcp_port); + printk("dlm: Can't listen on port %d\n", dlm_config.ci_tcp_port); sock_release(sock); sock = NULL; goto create_out; @@ -709,6 +678,7 @@ void *dlm_lowcomms_get_buffer(int nodeid, int len, if (!con) return NULL; + spin_lock(&con->writequeue_lock); e = list_entry(con->writequeue.prev, struct writequeue_entry, list); if ((&e->list == &con->writequeue) || (PAGE_CACHE_SIZE - e->end < len)) { @@ -747,6 +717,7 @@ void dlm_lowcomms_commit_buffer(void *mh) struct connection *con = e->con; int users; + spin_lock(&con->writequeue_lock); users = --e->users; if (users) goto out; @@ -754,12 +725,8 @@ void dlm_lowcomms_commit_buffer(void *mh) kunmap(e->page); spin_unlock(&con->writequeue_lock); - if (test_and_set_bit(CF_WRITE_PENDING, &con->flags) == 0) { - spin_lock_bh(&write_sockets_lock); - list_add_tail(&con->write_list, &write_sockets); - spin_unlock_bh(&write_sockets_lock); - - wake_up_interruptible(&lowcomms_send_waitq); + if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) { + queue_work(send_workqueue, &con->swork); } return; @@ -783,7 +750,7 @@ static void send_to_sock(struct connection *con) struct writequeue_entry *e; int len, offset; - down_read(&con->sock_sem); + mutex_lock(&con->sock_mutex); if (con->sock == NULL) goto out_connect; @@ -800,6 +767,7 @@ static void send_to_sock(struct connection *con) offset = e->offset; BUG_ON(len == 0 && e->users == 0); spin_unlock(&con->writequeue_lock); + kmap(e->page); ret = 0; if (len) { @@ -828,18 +796,18 @@ static void send_to_sock(struct connection *con) } spin_unlock(&con->writequeue_lock); out: - up_read(&con->sock_sem); + mutex_unlock(&con->sock_mutex); return; send_error: - up_read(&con->sock_sem); + mutex_unlock(&con->sock_mutex); close_connection(con, false); lowcomms_connect_sock(con); return; out_connect: - up_read(&con->sock_sem); - lowcomms_connect_sock(con); + mutex_unlock(&con->sock_mutex); + connect_to_sock(con); return; } @@ -872,7 +840,6 @@ int dlm_lowcomms_close(int nodeid) if (con) { clean_one_writequeue(con); close_connection(con, true); - atomic_set(&con->waiting_requests, 0); } return 0; @@ -880,102 +847,29 @@ out: return -1; } -/* API send message call, may queue the request */ -/* N.B. This is the old interface - use the new one for new calls */ -int lowcomms_send_message(int nodeid, char *buf, int len, gfp_t allocation) -{ - struct writequeue_entry *e; - char *b; - - e = dlm_lowcomms_get_buffer(nodeid, len, allocation, &b); - if (e) { - memcpy(b, buf, len); - dlm_lowcomms_commit_buffer(e); - return 0; - } - return -ENOBUFS; -} - /* Look for activity on active sockets */ -static void process_sockets(void) +static void process_recv_sockets(struct work_struct *work) { - struct list_head *list; - struct list_head *temp; - int count = 0; - - spin_lock_bh(&read_sockets_lock); - list_for_each_safe(list, temp, &read_sockets) { - - struct connection *con = - list_entry(list, struct connection, read_list); - list_del(&con->read_list); - clear_bit(CF_READ_PENDING, &con->flags); - - spin_unlock_bh(&read_sockets_lock); - - /* This can reach zero if we are processing requests - * as they come in. - */ - if (atomic_read(&con->waiting_requests) == 0) { - spin_lock_bh(&read_sockets_lock); - continue; - } - - do { - con->rx_action(con); - - /* Don't starve out everyone else */ - if (++count >= MAX_RX_MSG_COUNT) { - cond_resched(); - count = 0; - } + struct connection *con = container_of(work, struct connection, rwork); + int err; - } while (!atomic_dec_and_test(&con->waiting_requests) && - !kthread_should_stop()); - - spin_lock_bh(&read_sockets_lock); - } - spin_unlock_bh(&read_sockets_lock); + clear_bit(CF_READ_PENDING, &con->flags); + do { + err = con->rx_action(con); + } while (!err); } -/* Try to send any messages that are pending - */ -static void process_output_queue(void) -{ - struct list_head *list; - struct list_head *temp; - - spin_lock_bh(&write_sockets_lock); - list_for_each_safe(list, temp, &write_sockets) { - struct connection *con = - list_entry(list, struct connection, write_list); - clear_bit(CF_WRITE_PENDING, &con->flags); - list_del(&con->write_list); - spin_unlock_bh(&write_sockets_lock); - send_to_sock(con); - spin_lock_bh(&write_sockets_lock); - } - spin_unlock_bh(&write_sockets_lock); -} - -static void process_state_queue(void) +static void process_send_sockets(struct work_struct *work) { - struct list_head *list; - struct list_head *temp; - - spin_lock_bh(&state_sockets_lock); - list_for_each_safe(list, temp, &state_sockets) { - struct connection *con = - list_entry(list, struct connection, state_list); - list_del(&con->state_list); - clear_bit(CF_CONNECT_PENDING, &con->flags); - spin_unlock_bh(&state_sockets_lock); + struct connection *con = container_of(work, struct connection, swork); + if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) { connect_to_sock(con); - spin_lock_bh(&state_sockets_lock); } - spin_unlock_bh(&state_sockets_lock); + + clear_bit(CF_WRITE_PENDING, &con->flags); + send_to_sock(con); } @@ -992,109 +886,33 @@ static void clean_writequeues(void) } } -static int read_list_empty(void) -{ - int status; - - spin_lock_bh(&read_sockets_lock); - status = list_empty(&read_sockets); - spin_unlock_bh(&read_sockets_lock); - - return status; -} - -/* DLM Transport comms receive daemon */ -static int dlm_recvd(void *data) +static void work_stop(void) { - init_waitqueue_entry(&lowcomms_recv_waitq_head, current); - add_wait_queue(&lowcomms_recv_waitq, &lowcomms_recv_waitq_head); - - while (!kthread_should_stop()) { - set_current_state(TASK_INTERRUPTIBLE); - if (read_list_empty()) - cond_resched(); - set_current_state(TASK_RUNNING); - - process_sockets(); - } - - return 0; + destroy_workqueue(recv_workqueue); + destroy_workqueue(send_workqueue); } -static int write_and_state_lists_empty(void) +static int work_start(void) { - int status; - - spin_lock_bh(&write_sockets_lock); - status = list_empty(&write_sockets); - spin_unlock_bh(&write_sockets_lock); - - spin_lock_bh(&state_sockets_lock); - if (list_empty(&state_sockets) == 0) - status = 0; - spin_unlock_bh(&state_sockets_lock); - - return status; -} - -/* DLM Transport send daemon */ -static int dlm_sendd(void *data) -{ - init_waitqueue_entry(&lowcomms_send_waitq_head, current); - add_wait_queue(&lowcomms_send_waitq, &lowcomms_send_waitq_head); - - while (!kthread_should_stop()) { - set_current_state(TASK_INTERRUPTIBLE); - if (write_and_state_lists_empty()) - cond_resched(); - set_current_state(TASK_RUNNING); - - process_state_queue(); - process_output_queue(); - } - - return 0; -} - -static void daemons_stop(void) -{ - kthread_stop(recv_task); - kthread_stop(send_task); -} - -static int daemons_start(void) -{ - struct task_struct *p; int error; - - p = kthread_run(dlm_recvd, NULL, "dlm_recvd"); - error = IS_ERR(p); + recv_workqueue = create_workqueue("dlm_recv"); + error = IS_ERR(recv_workqueue); if (error) { - log_print("can't start dlm_recvd %d", error); + log_print("can't start dlm_recv %d", error); return error; } - recv_task = p; - p = kthread_run(dlm_sendd, NULL, "dlm_sendd"); - error = IS_ERR(p); + send_workqueue = create_singlethread_workqueue("dlm_send"); + error = IS_ERR(send_workqueue); if (error) { - log_print("can't start dlm_sendd %d", error); - kthread_stop(recv_task); + log_print("can't start dlm_send %d", error); + destroy_workqueue(recv_workqueue); return error; } - send_task = p; return 0; } -/* - * Return the largest buffer size we can cope with. - */ -int lowcomms_max_buffer_size(void) -{ - return PAGE_CACHE_SIZE; -} - void dlm_lowcomms_stop(void) { int i; @@ -1107,7 +925,7 @@ void dlm_lowcomms_stop(void) connections[i]->flags |= 0xFF; } - daemons_stop(); + work_stop(); clean_writequeues(); for (i = 0; i < conn_array_size; i++) { @@ -1159,7 +977,7 @@ int dlm_lowcomms_start(void) if (error) goto fail_unlisten; - error = daemons_start(); + error = work_start(); if (error) goto fail_unlisten; |