MEDIUM: mux-fcgi: merge recv_wait and send_wait event notifications
This is the last of the "recv_wait+send_wait merge" patches and is
functionally equivalent to previous commit "MEDIUM: mux-h2: merge
recv_wait and send_wait event notifications" but for FCGI this time.
The principle is pretty much the same, since the code is very similar.
We use a single wait_event for both recv and send and rely on the
subscribe flags to know the desired notifications.
diff --git a/src/mux_fcgi.c b/src/mux_fcgi.c
index bad2e30..8e98f1b 100644
--- a/src/mux_fcgi.c
+++ b/src/mux_fcgi.c
@@ -164,8 +164,7 @@
struct buffer rxbuf; /* receive buffer, always valid (buf_empty or real buffer) */
struct eb32_node by_id; /* place in fcgi_conn's streams_by_id */
- struct wait_event *recv_wait; /* Address of the wait_event the conn_stream associated is waiting on */
- struct wait_event *send_wait; /* Address of the wait_event the conn_stream associated is waiting on */
+ struct wait_event *subs; /* Address of the wait_event the conn_stream associated is waiting on */
struct list send_list; /* To be used when adding in fcgi_conn->send_list */
struct tasklet *shut_tl; /* deferred shutdown tasklet, to retry to close after we failed to by lack of space */
};
@@ -911,29 +910,25 @@
/* Attempts to notify the data layer of recv availability */
static void fcgi_strm_notify_recv(struct fcgi_strm *fstrm)
{
- struct wait_event *sw;
-
- if (fstrm->recv_wait) {
+ if (fstrm->subs && (fstrm->subs->events & SUB_RETRY_RECV)) {
TRACE_POINT(FCGI_EV_STRM_WAKE, fstrm->fconn->conn, fstrm);
- sw = fstrm->recv_wait;
- sw->events &= ~SUB_RETRY_RECV;
- tasklet_wakeup(sw->tasklet);
- fstrm->recv_wait = NULL;
+ tasklet_wakeup(fstrm->subs->tasklet);
+ fstrm->subs->events &= ~SUB_RETRY_RECV;
+ if (!fstrm->subs->events)
+ fstrm->subs = NULL;
}
}
/* Attempts to notify the data layer of send availability */
static void fcgi_strm_notify_send(struct fcgi_strm *fstrm)
{
- struct wait_event *sw;
-
- if (fstrm->send_wait) {
+ if (fstrm->subs && (fstrm->subs->events & SUB_RETRY_SEND)) {
TRACE_POINT(FCGI_EV_STRM_WAKE, fstrm->fconn->conn, fstrm);
- sw = fstrm->send_wait;
- sw->events &= ~SUB_RETRY_SEND;
fstrm->flags |= FCGI_SF_NOTIFIED;
- tasklet_wakeup(sw->tasklet);
- fstrm->send_wait = NULL;
+ tasklet_wakeup(fstrm->subs->tasklet);
+ fstrm->subs->events &= ~SUB_RETRY_SEND;
+ if (!fstrm->subs->events)
+ fstrm->subs = NULL;
}
else if (fstrm->flags & (FCGI_SF_WANT_SHUTR | FCGI_SF_WANT_SHUTW)) {
TRACE_POINT(FCGI_EV_STRM_WAKE, fstrm->fconn->conn, fstrm);
@@ -953,7 +948,7 @@
static void fcgi_strm_alert(struct fcgi_strm *fstrm)
{
TRACE_POINT(FCGI_EV_STRM_WAKE, fstrm->fconn->conn, fstrm);
- if (fstrm->recv_wait || fstrm->send_wait ||
+ if (fstrm->subs ||
(fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW))) {
fcgi_strm_notify_recv(fstrm);
fcgi_strm_notify_send(fstrm);
@@ -1018,10 +1013,8 @@
b_free(&fstrm->rxbuf);
offer_buffers(NULL, tasks_run_queue);
}
- if (fstrm->send_wait != NULL)
- fstrm->send_wait->events &= ~SUB_RETRY_SEND;
- if (fstrm->recv_wait != NULL)
- fstrm->recv_wait->events &= ~SUB_RETRY_RECV;
+ if (fstrm->subs)
+ fstrm->subs->events = 0;
/* There's no need to explicitly call unsubscribe here, the only
* reference left would be in the fconn send_list/fctl_list, and if
* we're in it, we're getting out anyway
@@ -1054,8 +1047,7 @@
pool_free(pool_head_fcgi_strm, fstrm);
goto out;
}
- fstrm->send_wait = NULL;
- fstrm->recv_wait = NULL;
+ fstrm->subs = NULL;
fstrm->shut_tl->process = fcgi_deferred_shut;
fstrm->shut_tl->context = fstrm;
LIST_INIT(&fstrm->send_list);
@@ -2653,17 +2645,20 @@
/* If the sender changed his mind and unsubscribed, let's just
* remove the stream from the send_list.
*/
- if (!fstrm->send_wait &&
- !(fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW))) {
+ if (!(fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW)) &&
+ (!fstrm->subs || !(fstrm->subs->events & SUB_RETRY_SEND))) {
LIST_DEL_INIT(&fstrm->send_list);
continue;
}
- if (fstrm->send_wait) {
+
+ if (fstrm->subs && fstrm->subs->events & SUB_RETRY_SEND) {
TRACE_POINT(FCGI_EV_STRM_WAKE, fconn->conn, fstrm);
fstrm->flags &= ~FCGI_SF_BLK_ANY;
- fstrm->send_wait->events &= ~SUB_RETRY_SEND;
fstrm->flags |= FCGI_SF_NOTIFIED;
- tasklet_wakeup(fstrm->send_wait->tasklet);
+ tasklet_wakeup(fstrm->subs->tasklet);
+ fstrm->subs->events &= ~SUB_RETRY_SEND;
+ if (!fstrm->subs->events)
+ fstrm->subs = NULL;
} else {
/* it's the shut request that was queued */
TRACE_POINT(FCGI_EV_STRM_WAKE, fconn->conn, fstrm);
@@ -2868,17 +2863,20 @@
/* If the sender changed his mind and unsubscribed, let's just
* remove the stream from the send_list.
*/
- if (!fstrm->send_wait &&
- !(fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW))) {
+ if (!(fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW)) &&
+ (!fstrm->subs || !(fstrm->subs->events & SUB_RETRY_SEND))) {
LIST_DEL_INIT(&fstrm->send_list);
continue;
}
- if (fstrm->send_wait) {
- fstrm->flags &= ~FCGI_SF_BLK_ANY;
- fstrm->send_wait->events &= ~SUB_RETRY_SEND;
+
+ if (fstrm->subs && fstrm->subs->events & SUB_RETRY_SEND) {
TRACE_DEVEL("waking up pending stream", FCGI_EV_FCONN_SEND|FCGI_EV_STRM_WAKE, conn, fstrm);
- tasklet_wakeup(fstrm->send_wait->tasklet);
+ fstrm->flags &= ~FCGI_SF_BLK_ANY;
fstrm->flags |= FCGI_SF_NOTIFIED;
+ tasklet_wakeup(fstrm->subs->tasklet);
+ fstrm->subs->events &= ~SUB_RETRY_SEND;
+ if (!fstrm->subs->events)
+ fstrm->subs = NULL;
} else {
/* it's the shut request that was queued */
TRACE_POINT(FCGI_EV_STRM_WAKE, fconn->conn, fstrm);
@@ -3448,7 +3446,7 @@
if (!(cs->conn->flags & CO_FL_ERROR) &&
(fconn->state != FCGI_CS_CLOSED) &&
(fstrm->flags & (FCGI_SF_BLK_MBUSY|FCGI_SF_BLK_MROOM)) &&
- (fstrm->send_wait || fstrm->recv_wait || (fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW)))) {
+ (fstrm->subs || (fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW)))) {
TRACE_DEVEL("leaving on stream blocked", FCGI_EV_STRM_END|FCGI_EV_FSTRM_BLK, fconn->conn, fstrm);
return;
}
@@ -3699,37 +3697,31 @@
/* Called from the upper layer, to subscribe to events, such as being able to send.
* The <param> argument here is supposed to be a pointer to a wait_event struct
- * which will be passed to fstrm->recv_wait or fstrm->send_wait depending on the
- * event_type. The event_type must only be a combination of SUB_RETRY_RECV and
- * SUB_RETRY_SEND, other values will lead to -1 being returned. It always
- * returns 0 except for the error above.
+ * which will be passed to fstrm->subs. The event_type must only be a
+ * combination of SUB_RETRY_RECV and SUB_RETRY_SEND, other values will lead to -1
+ * being returned. It always returns 0 except for the error above.
*/
static int fcgi_subscribe(struct conn_stream *cs, int event_type, void *param)
{
- struct wait_event *sw;
+ struct wait_event *sw = param;
struct fcgi_strm *fstrm = cs->ctx;
struct fcgi_conn *fconn = fstrm->fconn;
+ BUG_ON(event_type & ~(SUB_RETRY_SEND|SUB_RETRY_RECV));
+ BUG_ON(fstrm->subs && fstrm->subs->events & event_type);
+ BUG_ON(fstrm->subs && fstrm->subs != sw);
+
- if (event_type & SUB_RETRY_RECV) {
+ sw->events |= event_type;
+ fstrm->subs = sw;
+
+ if (event_type & SUB_RETRY_RECV)
TRACE_DEVEL("unsubscribe(recv)", FCGI_EV_STRM_RECV, fconn->conn, fstrm);
- sw = param;
- BUG_ON(fstrm->recv_wait != NULL || (sw->events & SUB_RETRY_RECV));
- sw->events |= SUB_RETRY_RECV;
- fstrm->recv_wait = sw;
- event_type &= ~SUB_RETRY_RECV;
- }
+
if (event_type & SUB_RETRY_SEND) {
TRACE_DEVEL("unsubscribe(send)", FCGI_EV_STRM_SEND, fconn->conn, fstrm);
- sw = param;
- BUG_ON(fstrm->send_wait != NULL || (sw->events & SUB_RETRY_SEND));
- sw->events |= SUB_RETRY_SEND;
- fstrm->send_wait = sw;
if (!LIST_ADDED(&fstrm->send_list))
LIST_ADDQ(&fconn->send_list, &fstrm->send_list);
- event_type &= ~SUB_RETRY_SEND;
}
- if (event_type != 0)
- return -1;
return 0;
}
@@ -3740,26 +3732,25 @@
*/
static int fcgi_unsubscribe(struct conn_stream *cs, int event_type, void *param)
{
- struct wait_event *sw;
+ struct wait_event *sw = param;
struct fcgi_strm *fstrm = cs->ctx;
struct fcgi_conn *fconn = fstrm->fconn;
+ BUG_ON(event_type & ~(SUB_RETRY_SEND|SUB_RETRY_RECV));
+ BUG_ON(fstrm->subs && fstrm->subs != sw);
+
+ sw->events &= ~event_type;
+ if (!sw->events)
+ fstrm->subs = NULL;
+
- if (event_type & SUB_RETRY_RECV) {
+ if (event_type & SUB_RETRY_RECV)
TRACE_DEVEL("subscribe(recv)", FCGI_EV_STRM_RECV, fconn->conn, fstrm);
- sw = param;
- BUG_ON(fstrm->recv_wait != sw);
- sw->events &= ~SUB_RETRY_RECV;
- fstrm->recv_wait = NULL;
- }
+
if (event_type & SUB_RETRY_SEND) {
TRACE_DEVEL("subscribe(send)", FCGI_EV_STRM_SEND, fconn->conn, fstrm);
- sw = param;
- BUG_ON(fstrm->send_wait != sw);
+ fstrm->flags &= ~FCGI_SF_NOTIFIED;
if (!(fstrm->flags & (FCGI_SF_WANT_SHUTR|FCGI_SF_WANT_SHUTW)))
LIST_DEL_INIT(&fstrm->send_list);
- sw->events &= ~SUB_RETRY_SEND;
- fstrm->flags &= ~FCGI_SF_NOTIFIED;
- fstrm->send_wait = NULL;
}
return 0;
}