This patch introduces a retransmit functionality for a lowcomms message
handle. It's just allocates a new buffer and transmit it again, no
special handling about prioritize it because keeping bytestream in order.
To avoid another connection look some refactor was done to make a new
buffer allocation with a preexisting connection pointer.
Signed-off-by: Alexander Aring <aahri...@redhat.com>
---
fs/dlm/lowcomms.c | 85 ++++++++++++++++++++++++++++++++++++-----------
fs/dlm/lowcomms.h | 1 +
2 files changed, 67 insertions(+), 19 deletions(-)
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index d222e6088ab2..df9827ec12f3 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -126,6 +126,8 @@ struct writequeue_entry {
struct dlm_msg {
struct writequeue_entry *entry;
+ struct dlm_msg *orig_msg;
+ bool retransmit;
void *ppc;
int len;
int idx; /* new()/commit() idx exchange */
@@ -1055,6 +1057,10 @@ static void free_entry(struct writequeue_entry *e)
struct dlm_msg *msg, *tmp;
list_for_each_entry_safe(msg, tmp, &e->msgs, list) {
+ if (msg->orig_msg) {
+ msg->orig_msg->retransmit = false;
+ kref_put(&msg->orig_msg->ref, dlm_msg_release);
+ }
list_del(&msg->list);
kref_put(&msg->ref, dlm_msg_release);
}
@@ -1494,11 +1500,37 @@ static struct writequeue_entry *new_wq_entry(struct
connection *con, int len,
return e;
};
+static struct dlm_msg *dlm_lowcomms_new_msg_con(struct connection *con, int
len,
+ gfp_t allocation, char **ppc,
+ void (*cb)(struct dlm_mhandle
*mh),
+ struct dlm_mhandle *mh)
+{
+ struct writequeue_entry *e;
+ struct dlm_msg *msg;
+
+ msg = kzalloc(sizeof(*msg), allocation);
+ if (!msg)
+ return NULL;
+
+ kref_init(&msg->ref);
+
+ e = new_wq_entry(con, len, allocation, ppc, cb, mh);
+ if (!e) {
+ kfree(msg);
+ return NULL;
+ }
+
+ msg->ppc = *ppc;
+ msg->len = len;
+ msg->entry = e;
+
+ return msg;
+}
+
struct dlm_msg *dlm_lowcomms_new_msg(int nodeid, int len, gfp_t allocation,
char **ppc, void (*cb)(struct dlm_mhandle
*mh),
struct dlm_mhandle *mh)
{
- struct writequeue_entry *e;
struct connection *con;
struct dlm_msg *msg;
int idx;
@@ -1518,32 +1550,18 @@ struct dlm_msg *dlm_lowcomms_new_msg(int nodeid, int
len, gfp_t allocation,
return NULL;
}
- msg = kzalloc(sizeof(*msg), allocation);
+ msg = dlm_lowcomms_new_msg_con(con, len, allocation, ppc, cb, mh);
if (!msg) {
srcu_read_unlock(&connections_srcu, idx);
return NULL;
}
- kref_init(&msg->ref);
-
- e = new_wq_entry(con, len, allocation, ppc, cb, mh);
- if (!e) {
- srcu_read_unlock(&connections_srcu, idx);
- kfree(msg);
- return NULL;
- }
-
- msg->ppc = *ppc;
- msg->len = len;
- msg->entry = e;
-
/* we assume if successful commit must called */
msg->idx = idx;
-
return msg;
}
-void dlm_lowcomms_commit_msg(struct dlm_msg *msg)
+static void _dlm_lowcomms_commit_msg(struct dlm_msg *msg)
{
struct writequeue_entry *e = msg->entry;
struct connection *con = e->con;
@@ -1561,20 +1579,49 @@ void dlm_lowcomms_commit_msg(struct dlm_msg *msg)
spin_unlock(&con->writequeue_lock);
queue_work(send_workqueue, &con->swork);
- srcu_read_unlock(&connections_srcu, msg->idx);
return;
out:
spin_unlock(&con->writequeue_lock);
- srcu_read_unlock(&connections_srcu, msg->idx);
return;
}
+void dlm_lowcomms_commit_msg(struct dlm_msg *msg)
+{
+ _dlm_lowcomms_commit_msg(msg);
+ srcu_read_unlock(&connections_srcu, msg->idx);
+}
+
void dlm_lowcomms_put_msg(struct dlm_msg *msg)
{
kref_put(&msg->ref, dlm_msg_release);
}
+/* does not held connections_srcu, usage workqueue only */
+int dlm_lowcomms_resend_msg(struct dlm_msg *msg)
+{
+ struct dlm_msg *msg_resend;
+ char *ppc;
+
+ if (msg->retransmit)
+ return 1;
+
+ msg_resend = dlm_lowcomms_new_msg_con(msg->entry->con, msg->len,
+ GFP_ATOMIC, &ppc, NULL, NULL);
+ if (!msg_resend)
+ return -ENOMEM;
+
+ msg->retransmit = true;
+ kref_get(&msg->ref);
+ msg_resend->orig_msg = msg;
+
+ memcpy(ppc, msg->ppc, msg->len);
+ _dlm_lowcomms_commit_msg(msg_resend);
+ dlm_lowcomms_put_msg(msg_resend);
+
+ return 0;
+}
+
/* Send a message */
static void send_to_sock(struct connection *con)
{
diff --git a/fs/dlm/lowcomms.h b/fs/dlm/lowcomms.h
index cdb8f066f0d8..a4384826442c 100644
--- a/fs/dlm/lowcomms.h
+++ b/fs/dlm/lowcomms.h
@@ -27,6 +27,7 @@ struct dlm_msg *dlm_lowcomms_new_msg(int nodeid, int len,
gfp_t allocation,
struct dlm_mhandle *mh);
void dlm_lowcomms_commit_msg(struct dlm_msg *msg);
void dlm_lowcomms_put_msg(struct dlm_msg *msg);
+int dlm_lowcomms_resend_msg(struct dlm_msg *msg);
int dlm_lowcomms_connect_node(int nodeid);
int dlm_lowcomms_nodes_set_mark(int nodeid, unsigned int mark);
int dlm_lowcomms_addr(int nodeid, struct sockaddr_storage *addr, int len);
--
2.26.3
