diff options
| author | David Howells <dhowells@redhat.com> | 2024-12-04 07:46:45 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-12-09 13:48:27 -0800 |
| commit | 6396b48ac0a77165f9c2c40ab03d6c8188c89739 (patch) | |
| tree | 7d9d87eb371563b07799f2ae8b571786537c3157 /net/rxrpc/sendmsg.c | |
| parent | 976b0ca5aae741ef33f4cf4079a9a026331eae88 (diff) | |
rxrpc: Don't need barrier for ->tx_bottom and ->acks_hard_ack
We don't need a barrier for the ->tx_bottom value (which indicates the
lowest sequence still in the transmission queue) and the ->acks_hard_ack
value (which tracks the DATA packets hard-ack'd by the latest ACK packet
received and thus indicates which DATA packets can now be discarded) as the
app thread doesn't use either value as a reference to memory to access.
Rather, the app thread merely uses these as a guide to how much space is
available in the transmission queue
Change the code to use READ/WRITE_ONCE() instead.
Also, change rxrpc_check_tx_space() to use the same value for tx_bottom
throughout.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-18-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/rxrpc/sendmsg.c')
| -rw-r--r-- | net/rxrpc/sendmsg.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c index 786c1fb1369a..467c9402882e 100644 --- a/net/rxrpc/sendmsg.c +++ b/net/rxrpc/sendmsg.c @@ -94,9 +94,11 @@ no_wait: */ static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win) { + rxrpc_seq_t tx_bottom = READ_ONCE(call->tx_bottom); + if (_tx_win) - *_tx_win = call->tx_bottom; - return call->tx_prepared - call->tx_bottom < 256; + *_tx_win = tx_bottom; + return call->tx_prepared - tx_bottom < 256; } /* @@ -138,7 +140,7 @@ static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx, rtt = 2; timeout = rtt; - tx_start = smp_load_acquire(&call->acks_hard_ack); + tx_start = READ_ONCE(call->acks_hard_ack); for (;;) { set_current_state(TASK_UNINTERRUPTIBLE); |