rxrpc: Abstract out the calculation of whether there's Tx space

Abstract out the calculation of there being sufficient Tx buffer space.
This is reproduced several times in the rxrpc sendmsg code.

Signed-off-by: David Howells <dhowells@redhat.com>

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 813fd68881429a8d8f029c2e819393f1f4d21b70..a13051d3809731f49b1b9402f78e3a280055f438 100644 (file)
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -17,6 +17,21 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
+/*
+ * Return true if there's sufficient Tx queue space.
+ */
+static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
+{
+       unsigned int win_size =
+               min_t(unsigned int, call->tx_winsize,
+                     call->cong_cwnd + call->cong_extra);
+       rxrpc_seq_t tx_win = READ_ONCE(call->tx_hard_ack);
+
+       if (_tx_win)
+               *_tx_win = tx_win;
+       return call->tx_top - tx_win < win_size;
+}
+
 /*
  * Wait for space to appear in the Tx queue or a signal to occur.
  */
@@ -26,9 +41,7 @@ static int rxrpc_wait_for_tx_window_intr(struct rxrpc_sock *rx,
 {
        for (;;) {
                set_current_state(TASK_INTERRUPTIBLE);
-               if (call->tx_top - call->tx_hard_ack <
-                   min_t(unsigned int, call->tx_winsize,
-                         call->cong_cwnd + call->cong_extra))
+               if (rxrpc_check_tx_space(call, NULL))
                        return 0;
 
                if (call->state >= RXRPC_CALL_COMPLETE)
@@ -68,9 +81,7 @@ static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
                set_current_state(TASK_UNINTERRUPTIBLE);
 
                tx_win = READ_ONCE(call->tx_hard_ack);
-               if (call->tx_top - tx_win <
-                   min_t(unsigned int, call->tx_winsize,
-                         call->cong_cwnd + call->cong_extra))
+               if (rxrpc_check_tx_space(call, &tx_win))
                        return 0;
 
                if (call->state >= RXRPC_CALL_COMPLETE)
@@ -302,9 +313,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
 
                        _debug("alloc");
 
-                       if (call->tx_top - call->tx_hard_ack >=
-                           min_t(unsigned int, call->tx_winsize,
-                                 call->cong_cwnd + call->cong_extra)) {
+                       if (!rxrpc_check_tx_space(call, NULL)) {
                                ret = -EAGAIN;
                                if (msg->msg_flags & MSG_DONTWAIT)
                                        goto maybe_error;