aboutgitcodebugslistschat
diff options
context:
space:
mode:
authorDavid Gibson <david@gibson.dropbear.id.au>2023-11-07 13:42:50 +1100
committerStefano Brivio <sbrivio@redhat.com>2023-11-07 09:54:21 +0100
commit515db1ecc4afd8d2a75ffdea031dd71aa6821342 (patch)
tree4a9c85bb13808bd5599db3a512e219b434310c78
parent7486cd13af311a5fd429a69ea5fe04f43cd78b49 (diff)
downloadpasst-515db1ecc4afd8d2a75ffdea031dd71aa6821342.tar
passt-515db1ecc4afd8d2a75ffdea031dd71aa6821342.tar.gz
passt-515db1ecc4afd8d2a75ffdea031dd71aa6821342.tar.bz2
passt-515db1ecc4afd8d2a75ffdea031dd71aa6821342.tar.lz
passt-515db1ecc4afd8d2a75ffdea031dd71aa6821342.tar.xz
passt-515db1ecc4afd8d2a75ffdea031dd71aa6821342.tar.zst
passt-515db1ecc4afd8d2a75ffdea031dd71aa6821342.zip
tcp_splice: Simplify selection of socket and pipe sides in socket handler
tcp_splice_sock_handler() uses the tcp_splice_dir() helper to select which of the socket, pipe and counter fields to use depending on which side of the connection the socket event is coming from. Now that we are using arrays for the two sides, rather than separate named fields, we can instead just use a variable indicating the side and use that to index the arrays whever we need a particular side's field. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
-rw-r--r--tcp_splice.c81
1 files changed, 22 insertions, 59 deletions
diff --git a/tcp_splice.c b/tcp_splice.c
index 9f84d4f..a5c1332 100644
--- a/tcp_splice.c
+++ b/tcp_splice.c
@@ -439,29 +439,6 @@ static int tcp_splice_new(const struct ctx *c, struct tcp_splice_conn *conn,
}
/**
- * tcp_splice_dir() - Set sockets/pipe pointers reflecting flow direction
- * @conn: Connection pointers
- * @ref_sock: Socket returned as reference from epoll
- * @reverse: Reverse direction: @ref_sock is used as destination
- * @from: Destination socket pointer to set
- * @to: Source socket pointer to set
- * @pipes: Pipe set, assigned on return
- */
-static void tcp_splice_dir(struct tcp_splice_conn *conn, int ref_sock,
- int reverse, int *from, int *to, int **pipes)
-{
- if (!reverse) {
- *from = ref_sock;
- *to = (*from == conn->s[0]) ? conn->s[1] : conn->s[0];
- } else {
- *to = ref_sock;
- *from = (*to == conn->s[0]) ? conn->s[1] : conn->s[0];
- }
-
- *pipes = *from == conn->s[0] ? conn->pipe[0] : conn->pipe[1];
-}
-
-/**
* tcp_splice_conn_from_sock() - Attempt to init state for a spliced connection
* @c: Execution context
* @ref: epoll reference of listening socket
@@ -521,8 +498,7 @@ void tcp_splice_sock_handler(struct ctx *c, struct tcp_splice_conn *conn,
int s, uint32_t events)
{
uint8_t lowat_set_flag, lowat_act_flag;
- int from, to, *pipes, eof, never_read;
- uint32_t *seq_read, *seq_write;
+ int fromside, eof, never_read;
if (conn->events == SPLICE_CLOSED)
return;
@@ -538,14 +514,15 @@ void tcp_splice_sock_handler(struct ctx *c, struct tcp_splice_conn *conn,
}
if (events & EPOLLOUT) {
- if (s == conn->s[0])
+ if (s == conn->s[0]) {
conn_event(c, conn, ~OUT_WAIT_0);
- else
+ fromside = 1;
+ } else {
conn_event(c, conn, ~OUT_WAIT_1);
-
- tcp_splice_dir(conn, s, 1, &from, &to, &pipes);
+ fromside = 0;
+ }
} else {
- tcp_splice_dir(conn, s, 0, &from, &to, &pipes);
+ fromside = s == conn->s[0] ? 0 : 1;
}
if (events & EPOLLRDHUP) {
@@ -566,24 +543,16 @@ swap:
eof = 0;
never_read = 1;
- if (from == conn->s[0]) {
- seq_read = &conn->read[0];
- seq_write = &conn->written[0];
- lowat_set_flag = RCVLOWAT_SET_0;
- lowat_act_flag = RCVLOWAT_ACT_0;
- } else {
- seq_read = &conn->read[1];
- seq_write = &conn->written[1];
- lowat_set_flag = RCVLOWAT_SET_1;
- lowat_act_flag = RCVLOWAT_ACT_1;
- }
+ lowat_set_flag = fromside == 0 ? RCVLOWAT_SET_0 : RCVLOWAT_SET_1;
+ lowat_act_flag = fromside == 0 ? RCVLOWAT_ACT_0 : RCVLOWAT_ACT_1;
while (1) {
ssize_t readlen, to_write = 0, written;
int more = 0;
retry:
- readlen = splice(from, NULL, pipes[1], NULL, c->tcp.pipe_size,
+ readlen = splice(conn->s[fromside], NULL,
+ conn->pipe[fromside][1], NULL, c->tcp.pipe_size,
SPLICE_F_MOVE | SPLICE_F_NONBLOCK);
trace("TCP (spliced): %li from read-side call", readlen);
if (readlen < 0) {
@@ -608,7 +577,8 @@ retry:
}
eintr:
- written = splice(pipes[0], NULL, to, NULL, to_write,
+ written = splice(conn->pipe[fromside][0], NULL,
+ conn->s[!fromside], NULL, to_write,
SPLICE_F_MOVE | more | SPLICE_F_NONBLOCK);
trace("TCP (spliced): %li from write-side call (passed %lu)",
written, to_write);
@@ -622,8 +592,8 @@ eintr:
readlen > (long)c->tcp.pipe_size / 10) {
int lowat = c->tcp.pipe_size / 4;
- setsockopt(from, SOL_SOCKET, SO_RCVLOWAT,
- &lowat, sizeof(lowat));
+ setsockopt(conn->s[fromside], SOL_SOCKET,
+ SO_RCVLOWAT, &lowat, sizeof(lowat));
conn_flag(c, conn, lowat_set_flag);
conn_flag(c, conn, lowat_act_flag);
@@ -632,8 +602,8 @@ eintr:
break;
}
- *seq_read += readlen > 0 ? readlen : 0;
- *seq_write += written > 0 ? written : 0;
+ conn->read[fromside] += readlen > 0 ? readlen : 0;
+ conn->written[fromside] += written > 0 ? written : 0;
if (written < 0) {
if (errno == EINTR)
@@ -645,10 +615,8 @@ eintr:
if (never_read)
break;
- if (to == conn->s[0])
- conn_event(c, conn, OUT_WAIT_0);
- else
- conn_event(c, conn, OUT_WAIT_1);
+ conn_event(c, conn,
+ fromside == 0 ? OUT_WAIT_1 : OUT_WAIT_0);
break;
}
@@ -665,14 +633,14 @@ eintr:
}
if ((conn->events & FIN_RCVD_0) && !(conn->events & FIN_SENT_1)) {
- if (*seq_read == *seq_write && eof) {
+ if (conn->read[fromside] == conn->written[fromside] && eof) {
shutdown(conn->s[1], SHUT_WR);
conn_event(c, conn, FIN_SENT_1);
}
}
if ((conn->events & FIN_RCVD_1) && !(conn->events & FIN_SENT_0)) {
- if (*seq_read == *seq_write && eof) {
+ if (conn->read[fromside] == conn->written[fromside] && eof) {
shutdown(conn->s[0], SHUT_WR);
conn_event(c, conn, FIN_SENT_0);
}
@@ -684,12 +652,7 @@ eintr:
if ((events & (EPOLLIN | EPOLLOUT)) == (EPOLLIN | EPOLLOUT)) {
events = EPOLLIN;
- SWAP(from, to);
- if (pipes == conn->pipe[0])
- pipes = conn->pipe[1];
- else
- pipes = conn->pipe[0];
-
+ fromside = !fromside;
goto swap;
}