From 66d5955a098d504b5a34c35d56a967c536264673 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Fri, 16 Jul 2021 16:22:39 -0400 Subject: fs: dlm: introduce con_next_wq helper This patch introduce a function to determine if something is ready to being send in the writequeue. It's not just that the writequeue is not empty additional the first entry need to have a valid length field. Signed-off-by: Alexander Aring Signed-off-by: David Teigland --- fs/dlm/lowcomms.c | 57 ++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 22 deletions(-) (limited to 'fs/dlm') diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c index 1bdd24bce709..9d21a8b9e9fb 100644 --- a/fs/dlm/lowcomms.c +++ b/fs/dlm/lowcomms.c @@ -175,6 +175,22 @@ static void sctp_connect_to_sock(struct connection *con); static void tcp_connect_to_sock(struct connection *con); static void dlm_tcp_shutdown(struct connection *con); +/* need to held writequeue_lock */ +static struct writequeue_entry *con_next_wq(struct connection *con) +{ + struct writequeue_entry *e; + + if (list_empty(&con->writequeue)) + return NULL; + + e = list_first_entry(&con->writequeue, struct writequeue_entry, + list); + if (e->len == 0) + return NULL; + + return e; +} + static struct connection *__find_con(int nodeid, int r) { struct connection *con; @@ -1646,10 +1662,9 @@ int dlm_lowcomms_resend_msg(struct dlm_msg *msg) /* Send a message */ static void send_to_sock(struct connection *con) { - int ret = 0; const int msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL; struct writequeue_entry *e; - int len, offset; + int len, offset, ret; int count = 0; mutex_lock(&con->sock_mutex); @@ -1658,7 +1673,8 @@ static void send_to_sock(struct connection *con) spin_lock(&con->writequeue_lock); for (;;) { - if (list_empty(&con->writequeue)) + e = con_next_wq(con); + if (!e) break; e = list_first_entry(&con->writequeue, struct writequeue_entry, list); @@ -1667,25 +1683,22 @@ static void send_to_sock(struct connection *con) BUG_ON(len == 0 && e->users == 0); spin_unlock(&con->writequeue_lock); - ret = 0; - if (len) { - ret = kernel_sendpage(con->sock, e->page, offset, len, - msg_flags); - if (ret == -EAGAIN || ret == 0) { - if (ret == -EAGAIN && - test_bit(SOCKWQ_ASYNC_NOSPACE, &con->sock->flags) && - !test_and_set_bit(CF_APP_LIMITED, &con->flags)) { - /* Notify TCP that we're limited by the - * application window size. - */ - set_bit(SOCK_NOSPACE, &con->sock->flags); - con->sock->sk->sk_write_pending++; - } - cond_resched(); - goto out; - } else if (ret < 0) - goto out; - } + ret = kernel_sendpage(con->sock, e->page, offset, len, + msg_flags); + if (ret == -EAGAIN || ret == 0) { + if (ret == -EAGAIN && + test_bit(SOCKWQ_ASYNC_NOSPACE, &con->sock->flags) && + !test_and_set_bit(CF_APP_LIMITED, &con->flags)) { + /* Notify TCP that we're limited by the + * application window size. + */ + set_bit(SOCK_NOSPACE, &con->sock->flags); + con->sock->sk->sk_write_pending++; + } + cond_resched(); + goto out; + } else if (ret < 0) + goto out; /* Don't starve people filling buffers */ if (++count >= MAX_SEND_MSG_COUNT) { -- cgit v1.2.3