flow, tcp: Add handling for per-flow timers

tcp_timer() scans the flow table so that it can run tcp_splice_timer() on
each spliced connection.  More generally, other flow types might want to
run similar timers in future.

We could add a flow_timer() analagous to tcp_timer(), udp_timer() etc.
However, this would need to scan the flow table, which we would have just
done in flow_defer_handler().  We'd prefer to just scan the flow table
once, dispatching both per-flow deferred events and per-flow timed events
if necessary.

So, extend flow_defer_handler() to do this.  For now we use the same timer
interval for all flow types (1s).  We can make that more flexible in future
if we need to.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/passt.c b/passt.c
index 5f72a28..870064f 100644
--- a/passt.c
+++ b/passt.c
@@ -53,8 +53,9 @@
 
 #define EPOLL_EVENTS		8
 
-#define __TIMER_INTERVAL	MIN(TCP_TIMER_INTERVAL, UDP_TIMER_INTERVAL)
-#define TIMER_INTERVAL		MIN(__TIMER_INTERVAL, ICMP_TIMER_INTERVAL)
+#define TIMER_INTERVAL__	MIN(TCP_TIMER_INTERVAL, UDP_TIMER_INTERVAL)
+#define TIMER_INTERVAL_		MIN(TIMER_INTERVAL__, ICMP_TIMER_INTERVAL)
+#define TIMER_INTERVAL		MIN(TIMER_INTERVAL_, FLOW_TIMER_INTERVAL)
 
 char pkt_buf[PKT_BUF_BYTES]	__attribute__ ((aligned(PAGE_SIZE)));
 
@@ -103,7 +104,7 @@ static void post_handler(struct ctx *c, const struct timespec *now)
 	/* NOLINTNEXTLINE(bugprone-branch-clone): intervals can be the same */
 	CALL_PROTO_HANDLER(c, now, icmp, ICMP);
 
-	flow_defer_handler(c);
+	flow_defer_handler(c, now);
 #undef CALL_PROTO_HANDLER
 }