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authorFlorin Coras <fcoras@cisco.com>2017-05-24 18:03:56 -0700
committerDave Barach <openvpp@barachs.net>2017-06-09 16:47:19 +0000
commit93992a9048cb6e5dcd22de5091e72de778122627 (patch)
treef295bb870ad1614d9327828dd036fb03f60e455e
parent583dc8d3e23a780c85ebe48ea59f0338aad4df17 (diff)
Implement sack based tcp loss recovery (RFC 6675)
- refactor existing congestion control code (RFC 6582/5681). Handling of ack feedback now consists of: ack parsing, cc event detection, event handling, congestion control update - extend sack scoreboard to support sack based retransmissions - basic implementation of Eifel detection algorithm (RFC 3522) for detecting spurious retransmissions - actually initialize the per-thread frame freelist hash tables - increase worker stack size to 2mb - fix session queue node out-of-buffer handling - ensure that the local buffer cache vec_len matches reality - avoid 2x spurious event requeues when short of buffers - count out-of-buffer events - make the builtin server thread-safe - fix bihash template threading issue: need to paint -1 across uninitialized working_copy_length vector elements (via rebase from master) Change-Id: I646cb9f1add9a67d08f4a87badbcb117980ebfc4 Signed-off-by: Florin Coras <fcoras@cisco.com> Signed-off-by: Dave Barach <dbarach@cisco.com>
Diffstat
-rw-r--r--src/svm/svm_fifo.c5
-rw-r--r--src/vlib/node.c1
-rw-r--r--src/vlib/threads.c2
-rw-r--r--src/vlib/threads.h2
-rw-r--r--src/vnet/session/node.c53
-rw-r--r--src/vnet/session/session.c11
-rw-r--r--src/vnet/session/session.h6
-rwxr-xr-xsrc/vnet/session/session_cli.c26
-rw-r--r--src/vnet/tcp/builtin_client.c40
-rw-r--r--src/vnet/tcp/builtin_server.c20
-rw-r--r--src/vnet/tcp/tcp.c57
-rw-r--r--src/vnet/tcp/tcp.h112
-rwxr-xr-xsrc/vnet/tcp/tcp_debug.h16
-rw-r--r--src/vnet/tcp/tcp_input.c671
-rw-r--r--src/vnet/tcp/tcp_newreno.c20
-rw-r--r--src/vnet/tcp/tcp_output.c287
-rw-r--r--src/vnet/tcp/tcp_test.c53
17 files changed, 973 insertions, 409 deletions
diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index f13f6fea..5c8f244a 100644
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -540,7 +540,7 @@ svm_fifo_peek (svm_fifo_t * f, u32 relative_offset, u32 max_bytes,
/* read cursize, which can only increase while we're working */
cursize = svm_fifo_max_dequeue (f);
- if (PREDICT_FALSE (cursize == 0))
+ if (PREDICT_FALSE (cursize < relative_offset))
return -2; /* nothing in the fifo */
nitems = f->nitems;
@@ -548,7 +548,8 @@ svm_fifo_peek (svm_fifo_t * f, u32 relative_offset, u32 max_bytes,
real_head = real_head >= nitems ? real_head - nitems : real_head;
/* Number of bytes we're going to copy */
- total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+ total_copy_bytes = (cursize - relative_offset < max_bytes) ?
+ cursize - relative_offset : max_bytes;
if (PREDICT_TRUE (copy_here != 0))
{
diff --git a/src/vlib/node.c b/src/vlib/node.c
index bbd3a42e..eecad274 100644
--- a/src/vlib/node.c
+++ b/src/vlib/node.c
@@ -502,6 +502,7 @@ vlib_node_main_init (vlib_main_t * vm)
vlib_node_t *n;
uword ni;
+ nm->frame_size_hash = hash_create (0, sizeof (uword));
nm->flags |= VLIB_NODE_MAIN_RUNTIME_STARTED;
/* Generate sibling relationships */
diff --git a/src/vlib/threads.c b/src/vlib/threads.c
index b7bc9e26..0c775e2d 100644
--- a/src/vlib/threads.c
+++ b/src/vlib/threads.c
@@ -670,7 +670,7 @@ start_workers (vlib_main_t * vm)
/* zap the (per worker) frame freelists, etc */
nm_clone->frame_sizes = 0;
- nm_clone->frame_size_hash = 0;
+ nm_clone->frame_size_hash = hash_create (0, sizeof (uword));
/* Packet trace buffers are guaranteed to be empty, nothing to do here */
diff --git a/src/vlib/threads.h b/src/vlib/threads.h
index 17d35a24..572ce77f 100644
--- a/src/vlib/threads.h
+++ b/src/vlib/threads.h
@@ -62,7 +62,7 @@ typedef struct vlib_thread_registration_
#define VLIB_CPU_MASK (VLIB_MAX_CPUS - 1) /* 0x3f, max */
#define VLIB_OFFSET_MASK (~VLIB_CPU_MASK)
-#define VLIB_LOG2_THREAD_STACK_SIZE (20)
+#define VLIB_LOG2_THREAD_STACK_SIZE (21)
#define VLIB_THREAD_STACK_SIZE (1<<VLIB_LOG2_THREAD_STACK_SIZE)
typedef enum
diff --git a/src/vnet/session/node.c b/src/vnet/session/node.c
index 3053ccc2..07eeae82 100644
--- a/src/vnet/session/node.c
+++ b/src/vnet/session/node.c
@@ -47,7 +47,8 @@ vlib_node_registration_t session_queue_node;
#define foreach_session_queue_error \
_(TX, "Packets transmitted") \
-_(TIMER, "Timer events")
+_(TIMER, "Timer events") \
+_(NO_BUFFER, "Out of buffers")
typedef enum
{
@@ -141,6 +142,7 @@ session_tx_fifo_read_and_snd_i (vlib_main_t * vm, vlib_node_runtime_t * node,
u8 *data0;
int i, n_bytes_read;
u32 n_bytes_per_buf, deq_per_buf;
+ u32 buffers_allocated, buffers_allocated_this_call;
next_index = next0 = session_type_to_next[s0->session_type];
@@ -167,9 +169,6 @@ session_tx_fifo_read_and_snd_i (vlib_main_t * vm, vlib_node_runtime_t * node,
/* Check how much we can pull. If buffering, subtract the offset */
max_dequeue0 = svm_fifo_max_dequeue (s0->server_tx_fifo) - rx_offset;
- /* Allow enqueuing of a new event */
- svm_fifo_unset_event (s0->server_tx_fifo);
-
/* Nothing to read return */
if (max_dequeue0 == 0)
return 0;
@@ -187,8 +186,8 @@ session_tx_fifo_read_and_snd_i (vlib_main_t * vm, vlib_node_runtime_t * node,
max_len_to_snd0 = snd_space0;
}
- n_bytes_per_buf = vlib_buffer_free_list_buffer_size (vm,
- VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
+ n_bytes_per_buf = vlib_buffer_free_list_buffer_size
+ (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
n_bytes_per_seg = MAX_HDRS_LEN + snd_mss0;
n_bufs_per_seg = ceil ((double) n_bytes_per_seg / n_bytes_per_buf);
n_bufs_per_evt = (ceil ((double) max_len_to_snd0 / n_bytes_per_seg))
@@ -205,24 +204,33 @@ session_tx_fifo_read_and_snd_i (vlib_main_t * vm, vlib_node_runtime_t * node,
if (PREDICT_FALSE (n_bufs < VLIB_FRAME_SIZE))
{
vec_validate (smm->tx_buffers[thread_index],
- n_bufs + VLIB_FRAME_SIZE - 1);
- n_bufs += vlib_buffer_alloc (vm,
- &smm->tx_buffers[thread_index][n_bufs],
- VLIB_FRAME_SIZE);
-
- /* buffer shortage
- * XXX 0.9 because when debugging we might not get a full frame */
- if (PREDICT_FALSE (n_bufs < 0.9 * VLIB_FRAME_SIZE))
+ n_bufs + 2 * VLIB_FRAME_SIZE - 1);
+
+ buffers_allocated = 0;
+ do
{
- if (svm_fifo_set_event (s0->server_tx_fifo))
- {
- vec_add1 (smm->pending_event_vector[thread_index], *e0);
- }
- return -1;
+ buffers_allocated_this_call =
+ vlib_buffer_alloc
+ (vm,
+ &smm->tx_buffers[thread_index][n_bufs + buffers_allocated],
+ 2 * VLIB_FRAME_SIZE - buffers_allocated);
+ buffers_allocated += buffers_allocated_this_call;
}
+ while (buffers_allocated_this_call > 0
+ && ((buffers_allocated + n_bufs < VLIB_FRAME_SIZE)));
+
+ n_bufs += buffers_allocated;
_vec_len (smm->tx_buffers[thread_index]) = n_bufs;
+
+ if (PREDICT_FALSE (n_bufs < VLIB_FRAME_SIZE))
+ {
+ vec_add1 (smm->pending_event_vector[thread_index], *e0);
+ return -1;
+ }
}
+ /* Allow enqueuing of a new event */
+ svm_fifo_unset_event (s0->server_tx_fifo);
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
while (left_to_snd0 && n_left_to_next >= n_bufs_per_seg)
@@ -232,7 +240,9 @@ session_tx_fifo_read_and_snd_i (vlib_main_t * vm, vlib_node_runtime_t * node,
*/
/* Get free buffer */
+ ASSERT (n_bufs >= 1);
bi0 = smm->tx_buffers[thread_index][--n_bufs];
+ ASSERT (bi0);
_vec_len (smm->tx_buffers[thread_index]) = n_bufs;
b0 = vlib_get_buffer (vm, bi0);
@@ -545,9 +555,10 @@ skip_dequeue:
my_thread_index,
&n_tx_packets);
/* Out of buffers */
- if (rv < 0)
+ if (PREDICT_FALSE (rv < 0))
{
- vec_add1 (smm->pending_event_vector[my_thread_index], *e0);
+ vlib_node_increment_counter (vm, node->node_index,
+ SESSION_QUEUE_ERROR_NO_BUFFER, 1);
continue;
}
break;
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c
index 02b0cced..534598d6 100644
--- a/src/vnet/session/session.c
+++ b/src/vnet/session/session.c
@@ -551,7 +551,7 @@ u8
stream_session_no_space (transport_connection_t * tc, u32 thread_index,
u16 data_len)
{
- stream_session_t *s = stream_session_get (tc->c_index, thread_index);
+ stream_session_t *s = stream_session_get (tc->s_index, thread_index);
if (PREDICT_FALSE (s->session_state != SESSION_STATE_READY))
return 1;
@@ -563,6 +563,15 @@ stream_session_no_space (transport_connection_t * tc, u32 thread_index,
}
u32
+stream_session_tx_fifo_max_dequeue (transport_connection_t * tc)
+{
+ stream_session_t *s = stream_session_get (tc->s_index, tc->thread_index);
+ if (s->session_state != SESSION_STATE_READY)
+ return 0;
+ return svm_fifo_max_dequeue (s->server_tx_fifo);
+}
+
+int
stream_session_peek_bytes (transport_connection_t * tc, u8 * buffer,
u32 offset, u32 max_bytes)
{
diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h
index a8728649..d9c38bd1 100644
--- a/src/vnet/session/session.h
+++ b/src/vnet/session/session.h
@@ -352,16 +352,18 @@ stream_session_max_rx_enqueue (transport_connection_t * tc)
}
always_inline u32
-stream_session_fifo_size (transport_connection_t * tc)
+stream_session_rx_fifo_size (transport_connection_t * tc)
{
stream_session_t *s = stream_session_get (tc->s_index, tc->thread_index);
return s->server_rx_fifo->nitems;
}
+u32 stream_session_tx_fifo_max_dequeue (transport_connection_t * tc);
+
int
stream_session_enqueue_data (transport_connection_t * tc, vlib_buffer_t * b,
u32 offset, u8 queue_event, u8 is_in_order);
-u32
+int
stream_session_peek_bytes (transport_connection_t * tc, u8 * buffer,
u32 offset, u32 max_bytes);
u32 stream_session_dequeue_drop (transport_connection_t * tc, u32 max_bytes);
diff --git a/src/vnet/session/session_cli.c b/src/vnet/session/session_cli.c
index 509eedbb..6b8341aa 100755
--- a/src/vnet/session/session_cli.c
+++ b/src/vnet/session/session_cli.c
@@ -15,6 +15,15 @@
#include <vnet/session/application.h>
#include <vnet/session/session.h>
+u8 *
+format_stream_session_fifos (u8 * s, va_list * args)
+{
+ stream_session_t *ss = va_arg (*args, stream_session_t *);
+ s = format (s, " Rx fifo: %U", format_svm_fifo, ss->server_rx_fifo, 1);
+ s = format (s, " Tx fifo: %U", format_svm_fifo, ss->server_tx_fifo, 1);
+ return s;
+}
+
/**
* Format stream session as per the following format
*
@@ -44,6 +53,8 @@ format_stream_session (u8 * s, va_list * args)
ss->thread_index, verbose);
if (verbose == 1)
s = format (s, "%v", str);
+ if (verbose > 1)
+ s = format (s, "%U", format_stream_session_fifos, ss);
}
else if (ss->session_state == SESSION_STATE_LISTENING)
{
@@ -57,8 +68,12 @@ format_stream_session (u8 * s, va_list * args)
}
else if (ss->session_state == SESSION_STATE_CLOSED)
{
- s = format (s, "[CL] %-40U%v", tp_vft->format_connection,
- ss->connection_index, ss->thread_index, verbose, str);
+ s = format (s, "[CL] %-40U", tp_vft->format_connection,
+ ss->connection_index, ss->thread_index, verbose);
+ if (verbose == 1)
+ s = format (s, "%v", str);
+ if (verbose > 1)
+ s = format (s, "%U", format_stream_session_fifos, ss);
}
else
{
@@ -124,13 +139,6 @@ show_session_command_fn (vlib_main_t * vm, unformat_input_t * input,
({
vec_reset_length (str);
str = format (str, "%U", format_stream_session, s, verbose);
- if (verbose > 1)
- {
- str = format (str, " Rx fifo: %U", format_svm_fifo,
- s->server_rx_fifo, 1);
- str = format (str, " Tx fifo: %U", format_svm_fifo,
- s->server_tx_fifo, 1);
- }
vlib_cli_output (vm, "%v", str);
}));
/* *INDENT-ON* */
diff --git a/src/vnet/tcp/builtin_client.c b/src/vnet/tcp/builtin_client.c
index 768f0c3c..7238cda3 100644
--- a/src/vnet/tcp/builtin_client.c
+++ b/src/vnet/tcp/builtin_client.c
@@ -115,8 +115,17 @@ receive_test_chunk (tclient_main_t * tm, session_t * s)
/* Allow enqueuing of new event */
// svm_fifo_unset_event (rx_fifo);
- n_read = svm_fifo_dequeue_nowait (rx_fifo, vec_len (tm->rx_buf),
- tm->rx_buf);
+ if (test_bytes)
+ {
+ n_read = svm_fifo_dequeue_nowait (rx_fifo, vec_len (tm->rx_buf),
+ tm->rx_buf);
+ }
+ else
+ {
+ n_read = svm_fifo_max_dequeue (rx_fifo);
+ svm_fifo_dequeue_drop (rx_fifo, n_read);
+ }
+
if (n_read > 0)
{
if (TCP_BUILTIN_CLIENT_DBG)
@@ -165,6 +174,8 @@ builtin_client_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
int i;
int delete_session;
u32 *connection_indices;
+ u32 tx_quota = 0;
+ u32 delta, prev_bytes_received_this_session;
connection_indices = tm->connection_index_by_thread[my_thread_index];
@@ -177,14 +188,19 @@ builtin_client_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
sp = pool_elt_at_index (tm->sessions, connection_indices[i]);
- if (sp->bytes_to_send > 0)
+ if (tx_quota < 60 && sp->bytes_to_send > 0)
{
send_test_chunk (tm, sp);
delete_session = 0;
+ tx_quota++;
}
if (sp->bytes_to_receive > 0)
{
+ prev_bytes_received_this_session = sp->bytes_received;
receive_test_chunk (tm, sp);
+ delta = sp->bytes_received - prev_bytes_received_this_session;
+ if (delta > 0)
+ tx_quota--;
delete_session = 0;
}
if (PREDICT_FALSE (delete_session == 1))
@@ -195,11 +211,19 @@ builtin_client_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
dmp->_vl_msg_id = ntohs (VL_API_DISCONNECT_SESSION);
dmp->client_index = tm->my_client_index;
dmp->handle = sp->vpp_session_handle;
- vl_msg_api_send_shmem (tm->vl_input_queue, (u8 *) & dmp);
- vec_delete (connection_indices, 1, i);
- tm->connection_index_by_thread[my_thread_index] =
- connection_indices;
- __sync_fetch_and_add (&tm->ready_connections, -1);
+// vl_msg_api_send_shmem (tm->vl_input_queue, (u8 *) & dmp);
+ if (!unix_shared_memory_queue_add (tm->vl_input_queue, (u8 *) & dmp,
+ 1))
+ {
+ vec_delete (connection_indices, 1, i);
+ tm->connection_index_by_thread[my_thread_index] =
+ connection_indices;
+ __sync_fetch_and_add (&tm->ready_connections, -1);
+ }
+ else
+ {
+ vl_msg_api_free (dmp);
+ }
/* Kick the debug CLI process */
if (tm->ready_connections == 0)
diff --git a/src/vnet/tcp/builtin_server.c b/src/vnet/tcp/builtin_server.c
index 4f0e211c..8bd2f360 100644
--- a/src/vnet/tcp/builtin_server.c
+++ b/src/vnet/tcp/builtin_server.c
@@ -39,7 +39,8 @@
typedef struct
{
- u8 *rx_buf;
+ /* Per-thread RX buffer */
+ u8 **rx_buf;
unix_shared_memory_queue_t **vpp_queue;
u64 byte_index;
@@ -117,13 +118,15 @@ void
test_bytes (builtin_server_main_t * bsm, int actual_transfer)
{
int i;
+ u32 my_thread_id = vlib_get_thread_index ();
for (i = 0; i < actual_transfer; i++)
{
- if (bsm->rx_buf[i] != ((bsm->byte_index + i) & 0xff))
+ if (bsm->rx_buf[my_thread_id][i] != ((bsm->byte_index + i) & 0xff))
{
clib_warning ("at %lld expected %d got %d", bsm->byte_index + i,
- (bsm->byte_index + i) & 0xff, bsm->rx_buf[i]);
+ (bsm->byte_index + i) & 0xff,
+ bsm->rx_buf[my_thread_id][i]);
}
}
bsm->byte_index += actual_transfer;
@@ -138,6 +141,7 @@ builtin_server_rx_callback (stream_session_t * s)
builtin_server_main_t *bsm = &builtin_server_main;
session_fifo_event_t evt;
static int serial_number = 0;
+ u32 my_thread_id = vlib_get_thread_index ();
tx_fifo = s->server_tx_fifo;
rx_fifo = s->server_rx_fifo;
@@ -171,11 +175,12 @@ builtin_server_rx_callback (stream_session_t * s)
return 0;
}
- vec_validate (bsm->rx_buf, max_transfer - 1);
- _vec_len (bsm->rx_buf) = max_transfer;
+ vec_validate (bsm->rx_buf, my_thread_id);
+ vec_validate (bsm->rx_buf[my_thread_id], max_transfer - 1);
+ _vec_len (bsm->rx_buf[my_thread_id]) = max_transfer;
actual_transfer = svm_fifo_dequeue_nowait (rx_fifo, max_transfer,
- bsm->rx_buf);
+ bsm->rx_buf[my_thread_id]);
ASSERT (actual_transfer == max_transfer);
// test_bytes (bsm, actual_transfer);
@@ -184,7 +189,8 @@ builtin_server_rx_callback (stream_session_t * s)
* Echo back
*/
- n_written = svm_fifo_enqueue_nowait (tx_fifo, actual_transfer, bsm->rx_buf);
+ n_written = svm_fifo_enqueue_nowait (tx_fifo, actual_transfer,
+ bsm->rx_buf[my_thread_id]);
if (n_written != max_transfer)
clib_warning ("short trout!");
diff --git a/src/vnet/tcp/tcp.c b/src/vnet/tcp/tcp.c
index 9b7b2f65..e0b67a8e 100644
--- a/src/vnet/tcp/tcp.c
+++ b/src/vnet/tcp/tcp.c
@@ -195,8 +195,8 @@ tcp_connection_close (tcp_connection_t * tc)
TCP_EVT_DBG (TCP_EVT_CLOSE, tc);
/* Send FIN if needed */
- if (tc->state == TCP_STATE_ESTABLISHED || tc->state == TCP_STATE_SYN_RCVD
- || tc->state == TCP_STATE_CLOSE_WAIT)
+ if (tc->state == TCP_STATE_ESTABLISHED
+ || tc->state == TCP_STATE_SYN_RCVD || tc->state == TCP_STATE_CLOSE_WAIT)
tcp_send_fin (tc);
/* Switch state */
@@ -480,7 +480,7 @@ u8 *
format_tcp_timers (u8 * s, va_list * args)
{
tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
- int i, last = 0;
+ int i, last = -1;
for (i = 0; i < TCP_N_TIMERS; i++)
if (tc->timers[i] != TCP_TIMER_HANDLE_INVALID)
@@ -493,7 +493,7 @@ format_tcp_timers (u8 * s, va_list * args)
s = format (s, "%s,", tcp_conn_timers[i]);
}
- if (last > 0)
+ if (last >= 0)
s = format (s, "%s]", tcp_conn_timers[i]);
else
s = format (s, "]");
@@ -526,19 +526,19 @@ format_tcp_vars (u8 * s, va_list * args)
s = format (s, " snd_wnd %u rcv_wnd %u snd_wl1 %u snd_wl2 %u\n",
tc->snd_wnd, tc->rcv_wnd, tc->snd_wl1 - tc->irs,
tc->snd_wl2 - tc->iss);
- s = format (s, " flight size %u send space %u rcv_wnd available %d\n",
- tcp_flight_size (tc), tcp_snd_space (tc),
- tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las));
+ s = format (s, " flight size %u send space %u rcv_wnd_av %d\n",
+ tcp_flight_size (tc), tcp_available_snd_space (tc),
+ tcp_rcv_wnd_available (tc));
s = format (s, " cong %U ", format_tcp_congestion_status, tc);
s = format (s, "cwnd %u ssthresh %u rtx_bytes %u bytes_acked %u\n",
- tc->cwnd, tc->ssthresh, tc->rtx_bytes, tc->bytes_acked);
- s = format (s, " prev_ssthresh %u snd_congestion %u\n", tc->prev_ssthresh,
- tc->snd_congestion - tc->iss);
+ tc->cwnd, tc->ssthresh, tc->snd_rxt_bytes, tc->bytes_acked);
+ s = format (s, " prev_ssthresh %u snd_congestion %u dupack %u\n",
+ tc->prev_ssthresh, tc->snd_congestion - tc->iss,
+ tc->rcv_dupacks);
s = format (s, " rto %u rto_boff %u srtt %u rttvar %u rtt_ts %u ", tc->rto,
tc->rto_boff, tc->srtt, tc->rttvar, tc->rtt_ts);
s = format (s, "rtt_seq %u\n", tc->rtt_seq);
- if (scoreboard_first_hole (&tc->sack_sb))
- s = format (s, " scoreboard: %U\n", format_tcp_scoreboard, &tc->sack_sb);
+ s = format (s, " scoreboard: %U\n", format_tcp_scoreboard, &tc->sack_sb);
if (vec_len (tc->snd_sacks))
s = format (s, " sacks tx: %U\n", format_tcp_sacks, tc);
@@ -595,9 +595,10 @@ format_tcp_session (u8 * s, va_list * args)
tc = tcp_connection_get (tci, thread_index);
if (tc)
- return format (s, "%U", format_tcp_connection, tc, verbose);
+ s = format (s, "%U", format_tcp_connection, tc, verbose);
else
- return format (s, "empty");
+ s = format (s, "empty");
+ return s;
}
u8 *
@@ -643,13 +644,17 @@ format_tcp_scoreboard (u8 * s, va_list * args)
{
sack_scoreboard_t *sb = va_arg (*args, sack_scoreboard_t *);
sack_scoreboard_hole_t *hole;
- s = format (s, "head %u tail %u snd_una_adv %u\n", sb->head, sb->tail,
- sb->snd_una_adv);
- s = format (s, "sacked_bytes %u last_sacked_bytes %u", sb->sacked_bytes,
- sb->last_sacked_bytes);
- s = format (s, " max_byte_sacked %u\n", sb->max_byte_sacked);
- s = format (s, "holes:\n");
+ s = format (s, "sacked_bytes %u last_sacked_bytes %u lost_bytes %u\n",
+ sb->sacked_bytes, sb->last_sacked_bytes, sb->lost_bytes);
+ s = format (s, " last_bytes_delivered %u high_sacked %u snd_una_adv %u\n",
+ sb->last_bytes_delivered, sb->high_sacked, sb->snd_una_adv);
+ s = format (s, " cur_rxt_hole %u high_rxt %u rescue_rxt %u",
+ sb->cur_rxt_hole, sb->high_rxt, sb->rescue_rxt);
+
hole = scoreboard_first_hole (sb);
+ if (hole)
+ s = format (s, "\n head %u tail %u holes:\n", sb->head, sb->tail);
+
while (hole)
{
s = format (s, "%U", format_tcp_sack_hole, hole);
@@ -736,7 +741,7 @@ tcp_snd_space (tcp_connection_t * tc)
if (tcp_in_recovery (tc))
{
tc->snd_nxt = tc->snd_una_max;
- snd_space = tcp_available_wnd (tc) - tc->rtx_bytes
+ snd_space = tcp_available_wnd (tc) - tc->snd_rxt_bytes
- (tc->snd_una_max - tc->snd_congestion);
if (snd_space <= 0 || (tc->snd_una_max - tc->snd_una) >= tc->snd_wnd)
return 0;
@@ -744,8 +749,8 @@ tcp_snd_space (tcp_connection_t * tc)
}
/* If in fast recovery, send 1 SMSS if wnd allows */
- if (tcp_in_fastrecovery (tc) && tcp_available_snd_space (tc)
- && tcp_fastrecovery_sent_1_smss (tc))
+ if (tcp_in_fastrecovery (tc)
+ && tcp_available_snd_space (tc) && !tcp_fastrecovery_sent_1_smss (tc))
{
tcp_fastrecovery_1_smss_on (tc);
return tc->snd_mss;
@@ -761,6 +766,12 @@ tcp_session_send_space (transport_connection_t * trans_conn)
return tcp_snd_space (tc);
}
+i32
+tcp_rcv_wnd_available (tcp_connection_t * tc)
+{
+ return (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
+}
+
u32
tcp_session_tx_fifo_offset (transport_connection_t * trans_conn)
{
diff --git a/src/vnet/tcp/tcp.h b/src/vnet/tcp/tcp.h
index c3ebe22b..071f1ab1 100644
--- a/src/vnet/tcp/tcp.h
+++ b/src/vnet/tcp/tcp.h
@@ -34,6 +34,7 @@
#define TCP_MAX_RX_FIFO_SIZE 2 << 20
#define TCP_IW_N_SEGMENTS 10
#define TCP_ALWAYS_ACK 0 /**< If on, we always ack */
+#define TCP_USE_SACKS 1 /**< Disable only for testing */
/** TCP FSM state definitions as per RFC793. */
#define foreach_tcp_fsm_state \
@@ -94,7 +95,7 @@ extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
#define TCP_DELACK_TIME 1 /* 0.1s */
#define TCP_ESTABLISH_TIME 750 /* 75s */
#define TCP_2MSL_TIME 300 /* 30s */
-#define TCP_CLOSEWAIT_TIME 1 /* 0.1s */
+#define TCP_CLOSEWAIT_TIME 20 /* 0.1s */
#define TCP_CLEANUP_TIME 5 /* 0.5s Time to wait before cleanup */
#define TCP_TIMER_PERSIST_MIN 2 /* 0.2s */
@@ -157,6 +158,7 @@ typedef struct _sack_scoreboard_hole
u32 prev; /**< Index for previous entry in linked list */
u32 start; /**< Start sequence number */
u32 end; /**< End sequence number */
+ u8 is_lost; /**< Mark hole as lost */
} sack_scoreboard_hole_t;
typedef struct _sack_scoreboard
@@ -166,8 +168,13 @@ typedef struct _sack_scoreboard
u32 tail; /**< Index of last entry */
u32 sacked_bytes; /**< Number of bytes sacked in sb */
u32 last_sacked_bytes; /**< Number of bytes last sacked */
+ u32 last_bytes_delivered; /**< Number of sack bytes delivered */
u32 snd_una_adv; /**< Bytes to add to snd_una */
- u32 max_byte_sacked; /**< Highest byte acked */
+ u32 high_sacked; /**< Highest byte sacked (fack) */
+ u32 high_rxt; /**< Highest retransmitted sequence */
+ u32 rescue_rxt; /**< Rescue sequence number */
+ u32 lost_bytes; /**< Bytes lost as per RFC6675 */
+ u32 cur_rxt_hole; /**< Retransmitting from this hole */
} sack_scoreboard_t;
typedef enum _tcp_cc_algorithm_type
@@ -211,7 +218,7 @@ typedef struct _tcp_connection
u32 irs; /**< initial remote sequence */
/* Options */
- tcp_options_t opt; /**< TCP connection options parsed */
+ tcp_options_t rcv_opts; /**< Rx options for connection */
tcp_options_t snd_opts; /**< Tx options for connection */
u8 snd_opts_len; /**< Tx options len */
u8 rcv_wscale; /**< Window scale to advertise to peer */
@@ -229,8 +236,10 @@ typedef struct _tcp_connection
u32 cwnd; /**< Congestion window */
u32 ssthresh; /**< Slow-start threshold */
u32 prev_ssthresh; /**< ssthresh before congestion */
+ u32 prev_cwnd; /**< ssthresh before congestion */
u32 bytes_acked; /**< Bytes acknowledged by current segment */
- u32 rtx_bytes; /**< Retransmitted bytes */
+ u32 snd_rxt_bytes; /**< Retransmitted bytes */
+ u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
u32 snd_congestion; /**< snd_una_max when congestion is detected */
tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
@@ -411,6 +420,7 @@ void tcp_send_syn (tcp_connection_t * tc);
void tcp_send_fin (tcp_connection_t * tc);
void tcp_init_mss (tcp_connection_t * tc);
void tcp_update_snd_mss (tcp_connection_t * tc);
+void tcp_update_rto (tcp_connection_t * tc);
always_inline u32
tcp_end_seq (tcp_header_t * th, u32 len)
@@ -428,17 +438,39 @@ tcp_end_seq (tcp_header_t * th, u32 len)
#define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
#define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
+/**
+ * Our estimate of the number of bytes that have left the network
+ */
+always_inline u32
+tcp_bytes_out (const tcp_connection_t * tc)
+{
+ if (tcp_opts_sack_permitted (&tc->rcv_opts))
+ return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
+ else
+ return tc->rcv_dupacks * tc->snd_mss;
+}
+
+/**
+ * Our estimate of the number of bytes in flight (pipe size)
+ */
always_inline u32
tcp_flight_size (const tcp_connection_t * tc)
{
int flight_size;
- flight_size = (int) ((tc->snd_una_max - tc->snd_una) + tc->rtx_bytes)
- - (tc->rcv_dupacks * tc->snd_mss) /* - tc->sack_sb.sacked_bytes */ ;
+ flight_size = (int) (tc->snd_una_max - tc->snd_una) - tcp_bytes_out (tc)
+ + tc->snd_rxt_bytes;
- /* Happens if we don't clear sacked bytes */
if (flight_size < 0)
- return 0;
+ {
+ if (0)
+ clib_warning
+ ("Negative: %u %u %u dupacks %u sacked bytes %u flags %d",
+ tc->snd_una_max - tc->snd_una, tcp_bytes_out (tc),
+ tc->snd_rxt_bytes, tc->rcv_dupacks, tc->sack_sb.sacked_bytes,
+ tc->rcv_opts.flags);
+ return 0;
+ }
return flight_size;
}
@@ -481,14 +513,17 @@ tcp_available_snd_space (const tcp_connection_t * tc)
return available_wnd - flight_size;
}
-u32 tcp_rcv_wnd_available (tcp_connection_t * tc);
+i32 tcp_rcv_wnd_available (tcp_connection_t * tc);
u32 tcp_snd_space (tcp_connection_t * tc);
void tcp_update_rcv_wnd (tcp_connection_t * tc);
void tcp_retransmit_first_unacked (tcp_connection_t * tc);
+void tcp_fast_retransmit_no_sack (tcp_connection_t * tc);
+void tcp_fast_retransmit_sack (tcp_connection_t * tc);
void tcp_fast_retransmit (tcp_connection_t * tc);
-void tcp_cc_congestion (tcp_connection_t * tc);
-void tcp_cc_recover (tcp_connection_t * tc);
+void tcp_cc_init_congestion (tcp_connection_t * tc);
+int tcp_cc_recover (tcp_connection_t * tc);
+void tcp_cc_fastrecovery_exit (tcp_connection_t * tc);
/* Made public for unit testing only */
void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
@@ -563,16 +598,16 @@ tcp_retransmit_timer_set (tcp_connection_t * tc)
}
always_inline void
-tcp_retransmit_timer_update (tcp_connection_t * tc)
+tcp_retransmit_timer_reset (tcp_connection_t * tc)
{
- tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
- clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
+ tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
}
always_inline void
-tcp_retransmit_timer_reset (tcp_connection_t * tc)
+tcp_retransmit_timer_force_update (tcp_connection_t * tc)
{
- tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
+ tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
+ clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
}
always_inline void
@@ -598,15 +633,43 @@ tcp_persist_timer_reset (tcp_connection_t * tc)
tcp_timer_reset (tc, TCP_TIMER_PERSIST);
}
+always_inline void
+tcp_retransmit_timer_update (tcp_connection_t * tc)
+{
+ if (tc->snd_una == tc->snd_una_max)
+ {
+ tcp_retransmit_timer_reset (tc);
+ if (tc->snd_wnd < tc->snd_mss)
+ tcp_persist_timer_set (tc);
+ }
+ else
+ tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
+ clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
+}
+
always_inline u8
tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
{
return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
}
+#define tcp_validate_txf_size(_tc, _a) \
+ ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
+ || stream_session_tx_fifo_max_dequeue (&_tc->connection) >= _a)
+
void
scoreboard_remove_hole (sack_scoreboard_t * sb,
sack_scoreboard_hole_t * hole);
+void scoreboard_update_lost (tcp_connection_t * tc, sack_scoreboard_t * sb);
+sack_scoreboard_hole_t *scoreboard_insert_hole (sack_scoreboard_t * sb,
+ u32 prev_index, u32 start,
+ u32 end);
+sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
+ sack_scoreboard_hole_t *
+ start, u8 have_sent_1_smss,
+ u8 * can_rescue,
+ u8 * snd_limited);
+void scoreboard_init_high_rxt (sack_scoreboard_t * sb);
always_inline sack_scoreboard_hole_t *
scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
@@ -625,6 +688,14 @@ scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
}
always_inline sack_scoreboard_hole_t *
+scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
+{
+ if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
+ return pool_elt_at_index (sb->holes, hole->prev);
+ return 0;
+}
+
+always_inline sack_scoreboard_hole_t *
scoreboard_first_hole (sack_scoreboard_t * sb)
{
if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
@@ -643,15 +714,19 @@ scoreboard_last_hole (sack_scoreboard_t * sb)
always_inline void
scoreboard_clear (sack_scoreboard_t * sb)
{
- sack_scoreboard_hole_t *hole = scoreboard_first_hole (sb);
+ sack_scoreboard_hole_t *hole;
while ((hole = scoreboard_first_hole (sb)))
{
scoreboard_remove_hole (sb, hole);
}
sb->sacked_bytes = 0;
sb->last_sacked_bytes = 0;
+ sb->last_bytes_delivered = 0;
sb->snd_una_adv = 0;
- sb->max_byte_sacked = 0;
+ sb->high_sacked = 0;
+ sb->high_rxt = 0;
+ sb->lost_bytes = 0;
+ sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
}
always_inline u32
@@ -671,6 +746,7 @@ scoreboard_init (sack_scoreboard_t * sb)
{
sb->head = TCP_INVALID_SACK_HOLE_INDEX;
sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
+ sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
}
void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
diff --git a/src/vnet/tcp/tcp_debug.h b/src/vnet/tcp/tcp_debug.h
index b4497a3b..3a16cf63 100755
--- a/src/vnet/tcp/tcp_debug.h
+++ b/src/vnet/tcp/tcp_debug.h
@@ -393,7 +393,7 @@ typedef enum _tcp_dbg_evt
DECLARE_ETD(_tc, _e, 4); \
ed->data[0] = _seq - _tc->irs; \
ed->data[1] = _end - _tc->irs; \
- ed->data[2] = _tc->opt.tsval; \
+ ed->data[2] = _tc->rcv_opts.tsval; \
ed->data[3] = _tc->tsval_recent; \
}
@@ -427,27 +427,27 @@ typedef enum _tcp_dbg_evt
{ \
ELOG_TYPE_DECLARE (_e) = \
{ \
- .format = "rtx: snd_nxt %u offset %u snd %u rtx %u", \
+ .format = "rxt: snd_nxt %u offset %u snd %u rxt %u", \
.format_args = "i4i4i4i4", \
}; \
DECLARE_ETD(_tc, _e, 4); \
ed->data[0] = _tc->snd_nxt - _tc->iss; \
ed->data[1] = offset; \
ed->data[2] = n_bytes; \
- ed->data[3] = _tc->rtx_bytes; \
+ ed->data[3] = _tc->snd_rxt_bytes; \
}
#define TCP_EVT_CC_EVT_HANDLER(_tc, _sub_evt, ...) \
{ \
ELOG_TYPE_DECLARE (_e) = \
{ \
- .format = "cc: %s wnd %u snd_cong %u rtx_bytes %u", \
+ .format = "cc: %s wnd %u snd_cong %u rxt_bytes %u", \
.format_args = "t4i4i4i4", \
.n_enum_strings = 5, \
.enum_strings = { \
- "fast-rtx", \
- "rtx-timeout", \
- "first-rtx", \
+ "fast-rxt", \
+ "rxt-timeout", \
+ "first-rxt", \
"recovered", \
"congestion", \
}, \
@@ -456,7 +456,7 @@ typedef enum _tcp_dbg_evt
ed->data[0] = _sub_evt; \
ed->data[1] = tcp_available_snd_space (_tc); \
ed->data[2] = _tc->snd_congestion - _tc->iss; \
- ed->data[3] = _tc->rtx_bytes; \
+ ed->data[3] = _tc->snd_rxt_bytes; \
}
#define TCP_EVT_CC_PACK_HANDLER(_tc, ...) \
diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c
index 35bc9094..ff2229b3 100644
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -231,8 +231,8 @@ tcp_options_parse (tcp_header_t * th, tcp_options_t * to)
always_inline int
tcp_segment_check_paws (tcp_connection_t * tc)
{
- return tcp_opts_tstamp (&tc->opt) && tc->tsval_recent
- && timestamp_lt (tc->opt.tsval, tc->tsval_recent);
+ return tcp_opts_tstamp (&tc->rcv_opts) && tc->tsval_recent
+ && timestamp_lt (tc->rcv_opts.tsval, tc->tsval_recent);
}
/**
@@ -248,10 +248,10 @@ tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
* then the TSval from the segment is copied to TS.Recent;
* otherwise, the TSval is ignored.
*/
- if (tcp_opts_tstamp (&tc->opt) && tc->tsval_recent
+ if (tcp_opts_tstamp (&tc->rcv_opts) && tc->tsval_recent
&& seq_leq (seq, tc->rcv_las) && seq_leq (tc->rcv_las, seq_end))
{
- tc->tsval_recent = tc->opt.tsval;
+ tc->tsval_recent = tc->rcv_opts.tsval;
tc->tsval_recent_age = tcp_time_now ();
}
}
@@ -272,14 +272,21 @@ tcp_segment_validate (vlib_main_t * vm, tcp_connection_t * tc0,
if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
return -1;
- if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->opt)))
+ if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->rcv_opts)))
{
return -1;
}
if (tcp_segment_check_paws (tc0))
{
- clib_warning ("paws failed");
+ if (CLIB_DEBUG > 2)
+ {
+ clib_warning ("paws failed\n%U", format_tcp_connection, tc0, 2);
+ clib_warning ("seq %u seq_end %u ack %u",
+ vnet_buffer (b0)->tcp.seq_number - tc0->irs,
+ vnet_buffer (b0)->tcp.seq_end - tc0->irs,
+ vnet_buffer (b0)->tcp.ack_number - tc0->iss);
+ }
TCP_EVT_DBG (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
vnet_buffer (b0)->tcp.seq_end);
@@ -348,7 +355,6 @@ tcp_segment_validate (vlib_main_t * vm, tcp_connection_t * tc0,
/* If segment in window, save timestamp */
tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
vnet_buffer (b0)->tcp.seq_end);
-
return 0;
}
@@ -391,6 +397,12 @@ tcp_estimate_rtt (tcp_connection_t * tc, u32 mrtt)
}
}
+void
+tcp_update_rto (tcp_connection_t * tc)
+{
+ tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
+}
+
/** Update RTT estimate and RTO timer
*
* Measure RTT: We have two sources of RTT measurements: TSOPT and ACK
@@ -405,7 +417,7 @@ tcp_update_rtt (tcp_connection_t * tc, u32 ack)
u32 mrtt = 0;
u8 rtx_acked;
- /* Determine if only rtx bytes are acked. TODO fast retransmit */
+ /* Determine if only rtx bytes are acked. TODO XXX fast retransmit */
rtx_acked = tc->rto_boff && (tc->bytes_acked <= tc->snd_mss);
/* Karn's rule, part 1. Don't use retransmitted segments to estimate
@@ -418,9 +430,10 @@ tcp_update_rtt (tcp_connection_t * tc, u32 ack)
* snd_una, i.e., the left side of the send window:
* seq_lt (tc->snd_una, ack). Note: last condition could be dropped, we don't
* try to update rtt for dupacks */
- else if (tcp_opts_tstamp (&tc->opt) && tc->opt.tsecr && tc->bytes_acked)
+ else if (tcp_opts_tstamp (&tc->rcv_opts) && tc->rcv_opts.tsecr
+ && tc->bytes_acked)
{
- mrtt = tcp_time_now () - tc->opt.tsecr;
+ mrtt = tcp_time_now () - tc->rcv_opts.tsecr;
}
/* Allow measuring of a new RTT */
@@ -436,7 +449,7 @@ tcp_update_rtt (tcp_connection_t * tc, u32 ack)
return 0;
tcp_estimate_rtt (tc, mrtt);
- tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
+ tcp_update_rto (tc);
return 0;
}
@@ -447,25 +460,46 @@ tcp_update_rtt (tcp_connection_t * tc, u32 ack)
static void
tcp_dequeue_acked (tcp_connection_t * tc, u32 ack)
{
- /* Dequeue the newly ACKed bytes */
- stream_session_dequeue_drop (&tc->connection, tc->bytes_acked);
+ /* Dequeue the newly ACKed add SACKed bytes */
+ stream_session_dequeue_drop (&tc->connection,
+ tc->bytes_acked + tc->sack_sb.snd_una_adv);
+
+ tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
/* Update rtt and rto */
tcp_update_rtt (tc, ack);
+
+ /* If everything has been acked, stop retransmit timer
+ * otherwise update. */
+ tcp_retransmit_timer_update (tc);
}
/**
- * Check if dupack as per RFC5681 Sec. 2
- *
- * This works only if called before updating snd_wnd.
- * */
-always_inline u8
-tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 new_snd_wnd)
+ * Check if duplicate ack as per RFC5681 Sec. 2
+ */
+static u8
+tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 prev_snd_wnd,
+ u32 prev_snd_una)
{
- return ((vnet_buffer (b)->tcp.ack_number == tc->snd_una)
+ return ((vnet_buffer (b)->tcp.ack_number == prev_snd_una)
&& seq_gt (tc->snd_una_max, tc->snd_una)
&& (vnet_buffer (b)->tcp.seq_end == vnet_buffer (b)->tcp.seq_number)
- && (new_snd_wnd == tc->snd_wnd));
+ && (prev_snd_wnd == tc->snd_wnd));
+}
+
+/**
+ * Checks if ack is a congestion control event.
+ */
+static u8
+tcp_ack_is_cc_event (tcp_connection_t * tc, vlib_buffer_t * b,
+ u32 prev_snd_wnd, u32 prev_snd_una, u8 * is_dack)
+{
+ /* Check if ack is duplicate. Per RFC 6675, ACKs that SACK new data are
+ * defined to be 'duplicate' */
+ *is_dack = tc->sack_sb.last_sacked_bytes
+ || tcp_ack_is_dupack (tc, b, prev_snd_wnd, prev_snd_una);
+
+ return (*is_dack || tcp_in_cong_recovery (tc));
}
void
@@ -478,6 +512,10 @@ scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
next = pool_elt_at_index (sb->holes, hole->next);
next->prev = hole->prev;
}
+ else
+ {
+ sb->tail = hole->prev;
+ }
if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
{
@@ -489,6 +527,9 @@ scoreboard_remove_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
sb->head = hole->next;
}
+ if (scoreboard_hole_index (sb, hole) == sb->cur_rxt_hole)
+ sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
+
pool_put (sb->holes, hole);
}
@@ -528,25 +569,130 @@ scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
}
void
+scoreboard_update_lost (tcp_connection_t * tc, sack_scoreboard_t * sb)
+{
+ sack_scoreboard_hole_t *hole, *prev;
+ u32 bytes = 0, blks = 0;
+
+ sb->lost_bytes = 0;
+ hole = scoreboard_last_hole (sb);
+ if (!hole)
+ return;
+
+ if (seq_gt (sb->high_sacked, hole->end))
+ {
+ bytes = sb->high_sacked - hole->end;
+ blks = 1;
+ }
+
+ while ((prev = scoreboard_prev_hole (sb, hole))
+ && (bytes < (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss
+ && blks < TCP_DUPACK_THRESHOLD))
+ {
+ bytes += hole->start - prev->end;
+ blks++;
+ hole = prev;
+ }
+
+ hole = prev;
+ while (hole)
+ {
+ sb->lost_bytes += scoreboard_hole_bytes (hole);
+ hole->is_lost = 1;
+ hole = scoreboard_prev_hole (sb, hole);
+ }
+}
+
+/**
+ * Figure out the next hole to retransmit
+ *
+ * Follows logic proposed in RFC6675 Sec. 4, NextSeg()
+ */
+sack_scoreboard_hole_t *
+scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
+ sack_scoreboard_hole_t * start,
+ u8 have_sent_1_smss,
+ u8 * can_rescue, u8 * snd_limited)
+{
+ sack_scoreboard_hole_t *hole = 0;
+
+ hole = start ? start : scoreboard_first_hole (sb);
+ while (hole && seq_leq (hole->end, sb->high_rxt) && hole->is_lost)
+ hole = scoreboard_next_hole (sb, hole);
+
+ /* Nothing, return */
+ if (!hole)
+ {
+ sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
+ return 0;
+ }
+
+ /* Rule (1): if higher than rxt, less than high_sacked and lost */
+ if (hole->is_lost && seq_lt (hole->start, sb->high_sacked))
+ {
+ sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
+ }
+ else
+ {
+ /* Rule (2): output takes care of transmitting new data */
+ if (!have_sent_1_smss)
+ {
+ hole = 0;
+ sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
+ }
+ /* Rule (3): if hole not lost */
+ else if (seq_lt (hole->start, sb->high_sacked))
+ {
+ *snd_limited = 1;
+ sb->cur_rxt_hole = scoreboard_hole_index (sb, hole);
+ }
+ /* Rule (4): if hole beyond high_sacked */
+ else
+ {
+ ASSERT (seq_geq (hole->start, sb->high_sacked));
+ *snd_limited = 1;
+ *can_rescue = 1;
+ /* HighRxt MUST NOT be updated */
+ return 0;
+ }
+ }
+
+ if (hole && seq_lt (sb->high_rxt, hole->start))
+ sb->high_rxt = hole->start;
+
+ return hole;
+}
+
+void
+scoreboard_init_high_rxt (sack_scoreboard_t * sb)
+{
+ sack_scoreboard_hole_t *hole;
+ hole = scoreboard_first_hole (sb);
+ sb->high_rxt = hole->start;
+ sb->cur_rxt_hole = sb->head;
+}
+
+void
tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
{
sack_scoreboard_t *sb = &tc->sack_sb;
sack_block_t *blk, tmp;
sack_scoreboard_hole_t *hole, *next_hole, *last_hole, *new_hole;
- u32 blk_index = 0, old_sacked_bytes, delivered_bytes, hole_index;
+ u32 blk_index = 0, old_sacked_bytes, hole_index;
int i, j;
sb->last_sacked_bytes = 0;
sb->snd_una_adv = 0;
old_sacked_bytes = sb->sacked_bytes;
- delivered_bytes = 0;
+ sb->last_bytes_delivered = 0;
- if (!tcp_opts_sack (&tc->opt) && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
+ if (!tcp_opts_sack (&tc->rcv_opts)
+ && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
return;
/* Remove invalid blocks */
- blk = tc->opt.sacks;
- while (blk < vec_end (tc->opt.sacks))
+ blk = tc->rcv_opts.sacks;
+ while (blk < vec_end (tc->rcv_opts.sacks))
{
if (seq_lt (blk->start, blk->end)
&& seq_gt (blk->start, tc->snd_una)
@@ -555,7 +701,7 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
blk++;
continue;
}
- vec_del1 (tc->opt.sacks, blk - tc->opt.sacks);
+ vec_del1 (tc->rcv_opts.sacks, blk - tc->rcv_opts.sacks);
}
/* Add block for cumulative ack */
@@ -563,20 +709,20 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
{
tmp.start = tc->snd_una;
tmp.end = ack;
- vec_add1 (tc->opt.sacks, tmp);
+ vec_add1 (tc->rcv_opts.sacks, tmp);
}
- if (vec_len (tc->opt.sacks) == 0)
+ if (vec_len (tc->rcv_opts.sacks) == 0)
return;
/* Make sure blocks are ordered */
- for (i = 0; i < vec_len (tc->opt.sacks); i++)
- for (j = i + 1; j < vec_len (tc->opt.sacks); j++)
- if (seq_lt (tc->opt.sacks[j].start, tc->opt.sacks[i].start))
+ for (i = 0; i < vec_len (tc->rcv_opts.sacks); i++)
+ for (j = i + 1; j < vec_len (tc->rcv_opts.sacks); j++)
+ if (seq_lt (tc->rcv_opts.sacks[j].start, tc->rcv_opts.sacks[i].start))
{
- tmp = tc->opt.sacks[i];
- tc->opt.sacks[i] = tc->opt.sacks[j];
- tc->opt.sacks[j] = tmp;
+ tmp = tc->rcv_opts.sacks[i];
+ tc->rcv_opts.sacks[i] = tc->rcv_opts.sacks[j];
+ tc->rcv_opts.sacks[j] = tmp;
}
if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
@@ -585,25 +731,25 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
tc->snd_una, tc->snd_una_max);
sb->tail = scoreboard_hole_index (sb, last_hole);
- tmp = tc->opt.sacks[vec_len (tc->opt.sacks) - 1];
- sb->max_byte_sacked = tmp.end;
+ tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
+ sb->high_sacked = tmp.end;
}
else
{
/* If we have holes but snd_una_max is beyond the last hole, update
* last hole end */
- tmp = tc->opt.sacks[vec_len (tc->opt.sacks) - 1];
+ tmp = tc->rcv_opts.sacks[vec_len (tc->rcv_opts.sacks) - 1];
last_hole = scoreboard_last_hole (sb);
- if (seq_gt (tc->snd_una_max, sb->max_byte_sacked)
+ if (seq_gt (tc->snd_una_max, sb->high_sacked)
&& seq_gt (tc->snd_una_max, last_hole->end))
last_hole->end = tc->snd_una_max;
}
/* Walk the holes with the SACK blocks */
hole = pool_elt_at_index (sb->holes, sb->head);
- while (hole && blk_index < vec_len (tc->opt.sacks))
+ while (hole && blk_index < vec_len (tc->rcv_opts.sacks))
{
- blk = &tc->opt.sacks[blk_index];
+ blk = &tc->rcv_opts.sacks[blk_index];
if (seq_leq (blk->start, hole->start))
{
@@ -617,9 +763,9 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
{
/* Bytes lost because snd_wnd left edge advances */
if (next_hole && seq_leq (next_hole->start, ack))
- delivered_bytes += next_hole->start - hole->end;
+ sb->last_bytes_delivered += next_hole->start - hole->end;
else
- delivered_bytes += ack - hole->end;
+ sb->last_bytes_delivered += ack - hole->end;
}
else
{
@@ -633,8 +779,8 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
last_hole = scoreboard_last_hole (sb);
/* keep track of max byte sacked for when the last hole
* is acked */
- if (seq_gt (hole->end, sb->max_byte_sacked))
- sb->max_byte_sacked = hole->end;
+ if (seq_gt (hole->end, sb->high_sacked))
+ sb->high_sacked = hole->end;
}
/* snd_una needs to be advanced */
@@ -645,12 +791,12 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
sb->snd_una_adv = next_hole->start - ack;
/* all these can be delivered */
- delivered_bytes += sb->snd_una_adv;
+ sb->last_bytes_delivered += sb->snd_una_adv;
}
else if (!next_hole)
{
- sb->snd_una_adv = sb->max_byte_sacked - ack;
- delivered_bytes += sb->snd_una_adv;
+ sb->snd_una_adv = sb->high_sacked - ack;
+ sb->last_bytes_delivered += sb->snd_una_adv;
}
}
@@ -691,28 +837,33 @@ tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
}
blk_index++;
- hole = scoreboard_next_hole (sb, hole);
}
- else
+ else if (seq_leq (blk->start, hole->end))
{
sb->sacked_bytes += hole->end - blk->start;
hole->end = blk->start;
- hole = scoreboard_next_hole (sb, hole);
}
+
+ hole = scoreboard_next_hole (sb, hole);
}
}
sb->last_sacked_bytes = sb->sacked_bytes - old_sacked_bytes;
- sb->sacked_bytes -= delivered_bytes;
+ sb->sacked_bytes -= sb->last_bytes_delivered;
+ scoreboard_update_lost (tc, sb);
}
-/** Update snd_wnd
+/**
+ * Try to update snd_wnd based on feedback received from peer.
*
- * If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
- * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
+ * If successful, and new window is 'effectively' 0, activate persist
+ * timer.
+ */
static void
tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
{
+ /* If (SND.WL1 < SEG.SEQ or (SND.WL1 = SEG.SEQ and SND.WL2 =< SEG.ACK)), set
+ * SND.WND <- SEG.WND, set SND.WL1 <- SEG.SEQ, and set SND.WL2 <- SEG.ACK */
if (seq_lt (tc->snd_wl1, seq)
|| (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
{
@@ -721,138 +872,269 @@ tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
tc->snd_wl2 = ack;
TCP_EVT_DBG (TCP_EVT_SND_WND, tc);
- /* Set probe timer if we just got 0 wnd */
if (tc->snd_wnd < tc->snd_mss)
{
- if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
+ /* Set persist timer if not set and we just got 0 wnd */
+ if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST)
+ && !tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT))
tcp_persist_timer_set (tc);
}
else
- tcp_persist_timer_reset (tc);
+ {
+ tcp_persist_timer_reset (tc);
+ if (!tcp_in_recovery (tc) && tc->rto_boff > 0)
+ {
+ tc->rto_boff = 0;
+ tcp_update_rto (tc);
+ }
+ }
}
}
void
-tcp_cc_congestion (tcp_connection_t * tc)
+tcp_cc_init_congestion (tcp_connection_t * tc)
{
- tc->snd_congestion = tc->snd_nxt;
+ tcp_fastrecovery_on (tc);
+ tc->snd_congestion = tc->snd_una_max;
tc->cc_algo->congestion (tc);
TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 4);
}
-void
-tcp_cc_recover (tcp_connection_t * tc)
+static void
+tcp_cc_recovery_exit (tcp_connection_t * tc)
{
- /* TODO: check if time to recover was small. It might be that RTO popped
- * too soon.
- */
+ /* Deflate rto */
+ tcp_update_rto (tc);
+ tc->rto_boff = 0;
+ tc->snd_rxt_ts = 0;
+ tcp_recovery_off (tc);
+}
+void
+tcp_cc_fastrecovery_exit (tcp_connection_t * tc)
+{
tc->cc_algo->recovered (tc);
+ tc->snd_rxt_bytes = 0;
+ tc->rcv_dupacks = 0;
+ tcp_fastrecovery_off (tc);
+ tcp_fastrecovery_1_smss_off (tc);
+}
- tc->rtx_bytes = 0;
+static void
+tcp_cc_congestion_undo (tcp_connection_t * tc)
+{
+ tc->cwnd = tc->prev_cwnd;
+ tc->ssthresh = tc->prev_ssthresh;
+ tc->snd_nxt = tc->snd_una_max;
tc->rcv_dupacks = 0;
- tc->snd_nxt = tc->snd_una;
+ if (tcp_in_recovery (tc))
+ tcp_cc_recovery_exit (tc);
+ ASSERT (tc->rto_boff == 0);
+ /* TODO extend for fastrecovery */
+}
- tc->cc_algo->rcv_ack (tc);
- tc->tsecr_last_ack = tc->opt.tsecr;
+static u8
+tcp_cc_is_spurious_retransmit (tcp_connection_t * tc)
+{
+ return (tc->snd_rxt_ts
+ && tcp_opts_tstamp (&tc->rcv_opts)
+ && timestamp_lt (tc->rcv_opts.tsecr, tc->snd_rxt_ts));
+}
- tcp_cong_recovery_off (tc);
+int
+tcp_cc_recover (tcp_connection_t * tc)
+{
+ ASSERT (tcp_in_cong_recovery (tc));
+ if (tcp_cc_is_spurious_retransmit (tc))
+ {
+ tcp_cc_congestion_undo (tc);
+ return 1;
+ }
+
+ if (tcp_in_recovery (tc))
+ tcp_cc_recovery_exit (tc);
+ else if (tcp_in_fastrecovery (tc))
+ tcp_cc_fastrecovery_exit (tc);
+
+ ASSERT (tc->rto_boff == 0);
+ ASSERT (!tcp_in_cong_recovery (tc));
TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 3);
+ return 0;
}
static void
-tcp_cc_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b)
+tcp_cc_update (tcp_connection_t * tc, vlib_buffer_t * b)
+{
+ ASSERT (!tcp_in_cong_recovery (tc));
+
+ /* Congestion avoidance */
+ tc->cc_algo->rcv_ack (tc);
+ tc->tsecr_last_ack = tc->rcv_opts.tsecr;
+
+ /* If a cumulative ack, make sure dupacks is 0 */
+ tc->rcv_dupacks = 0;
+
+ /* When dupacks hits the threshold we only enter fast retransmit if
+ * cumulative ack covers more than snd_congestion. Should snd_una
+ * wrap this test may fail under otherwise valid circumstances.
+ * Therefore, proactively update snd_congestion when wrap detected. */
+ if (PREDICT_FALSE
+ (seq_leq (tc->snd_congestion, tc->snd_una - tc->bytes_acked)
+ && seq_gt (tc->snd_congestion, tc->snd_una)))
+ tc->snd_congestion = tc->snd_una - 1;
+}
+
+static u8
+tcp_should_fastrecover_sack (tcp_connection_t * tc)
{
- u8 partial_ack;
- u32 bytes_advanced;
+ return (TCP_DUPACK_THRESHOLD - 1) * tc->snd_mss < tc->sack_sb.sacked_bytes;
+}
- if (tcp_in_fastrecovery (tc))
+static u8
+tcp_should_fastrecover (tcp_connection_t * tc)
+{
+ return (tc->rcv_dupacks == TCP_DUPACK_THRESHOLD
+ || tcp_should_fastrecover_sack (tc));
+}
+
+static void
+tcp_cc_handle_event (tcp_connection_t * tc, u32 is_dack)
+{
+ /*
+ * Duplicate ACK. Check if we should enter fast recovery, or if already in
+ * it account for the bytes that left the network.
+ */
+ if (is_dack)
{
- partial_ack = seq_lt (tc->snd_una, tc->snd_congestion);
- if (!partial_ack)
+ ASSERT (tc->snd_una != tc->snd_una_max
+ || tc->sack_sb.last_sacked_bytes);
+ tc->rcv_dupacks++;
+
+ if (tc->rcv_dupacks > TCP_DUPACK_THRESHOLD && !tc->bytes_acked)
{
- /* Clear retransmitted bytes. */
- tcp_cc_recover (tc);
+ ASSERT (tcp_in_fastrecovery (tc));
+ /* Pure duplicate ack. If some data got acked, it's handled lower */
+ tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
+ return;
}
- else
+ else if (tcp_should_fastrecover (tc))
{
- TCP_EVT_DBG (TCP_EVT_CC_PACK, tc);
+ /* Things are already bad */
+ if (tcp_in_cong_recovery (tc))
+ {
+ tc->rcv_dupacks = 0;
+ goto partial_ack_test;
+ }
- /* Clear retransmitted bytes. XXX should we clear all? */
- tc->rtx_bytes = 0;
+ /* If of of the two conditions lower hold, reset dupacks
+ * 1) Cumulative ack does not cover more than congestion threshold
+ * 2) RFC6582 heuristic to avoid multiple fast retransmits
+ */
+ if (seq_leq (tc->snd_una, tc->snd_congestion)
+ || tc->rcv_opts.tsecr != tc->tsecr_last_ack)
+ {
+ tc->rcv_dupacks = 0;
+ return;
+ }
+
+ tcp_cc_init_congestion (tc);
+ tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
- tc->cc_algo->rcv_cong_ack (tc, TCP_CC_PARTIALACK);
+ /* The first segment MUST be retransmitted */
+ tcp_retransmit_first_unacked (tc);
- /* In case snd_nxt is still in the past and output tries to
- * shove some new bytes */
- tc->snd_nxt = tc->snd_una_max;
+ /* Post retransmit update cwnd to ssthresh and account for the
+ * three segments that have left the network and should've been
+ * buffered at the receiver XXX */
+ tc->cwnd = tc->ssthresh + tc->rcv_dupacks * tc->snd_mss;
- /* XXX need proper RFC6675 support */
- if (tc->sack_sb.last_sacked_bytes && !tcp_in_recovery (tc))
+ /* If cwnd allows, send more data */
+ if (tcp_opts_sack_permitted (&tc->rcv_opts)
+ && scoreboard_first_hole (&tc->sack_sb))
{
- tcp_fast_retransmit (tc);
+ scoreboard_init_high_rxt (&tc->sack_sb);
+ tcp_fast_retransmit_sack (tc);
}
else
{
- /* Retransmit first unacked segment */
- tcp_retransmit_first_unacked (tc);
+ tcp_fast_retransmit_no_sack (tc);
}
+
+ return;
}
- }
- else
- {
- tc->cc_algo->rcv_ack (tc);
- tc->tsecr_last_ack = tc->opt.tsecr;
- tc->rcv_dupacks = 0;
- if (tcp_in_recovery (tc))
+ else if (!tc->bytes_acked
+ || (tc->bytes_acked && !tcp_in_cong_recovery (tc)))
{
- bytes_advanced = tc->bytes_acked + tc->sack_sb.snd_una_adv;
- tc->rtx_bytes -= clib_min (bytes_advanced, tc->rtx_bytes);
- tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
- if (seq_geq (tc->snd_una, tc->snd_congestion))
- {
- tc->rtx_bytes = 0;
- tcp_recovery_off (tc);
- }
+ tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
+ return;
}
+ else
+ goto partial_ack;
}
-}
-static void
-tcp_cc_rcv_dupack (tcp_connection_t * tc, u32 ack)
-{
-// ASSERT (seq_geq(tc->snd_una, ack));
+partial_ack_test:
+
+ if (!tc->bytes_acked)
+ return;
+
+partial_ack:
+ /*
+ * Legitimate ACK. 1) See if we can exit recovery
+ */
+ /* XXX limit this only to first partial ack? */
+ tcp_retransmit_timer_update (tc);
- tc->rcv_dupacks++;
- if (tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
+ if (seq_geq (tc->snd_una, tc->snd_congestion))
{
- /* RFC6582 NewReno heuristic to avoid multiple fast retransmits */
- if (tc->opt.tsecr != tc->tsecr_last_ack)
- {
- tc->rcv_dupacks = 0;
- return;
- }
+ /* If spurious return, we've already updated everything */
+ if (tcp_cc_recover (tc))
+ return;
+
+ tc->snd_nxt = tc->snd_una_max;
- tcp_fastrecovery_on (tc);
+ /* Treat as congestion avoidance ack */
+ tc->cc_algo->rcv_ack (tc);
+ tc->tsecr_last_ack = tc->rcv_opts.tsecr;
+ return;
+ }
+
+ /*
+ * Legitimate ACK. 2) If PARTIAL ACK try to retransmit
+ */
+ TCP_EVT_DBG (TCP_EVT_CC_PACK, tc);
+
+ /* RFC6675: If the incoming ACK is a cumulative acknowledgment,
+ * reset dupacks to 0 */
+ tc->rcv_dupacks = 0;
- /* Handle congestion and dupack */
- tcp_cc_congestion (tc);
- tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
+ tcp_retransmit_first_unacked (tc);
- tcp_fast_retransmit (tc);
+ /* Post RTO timeout don't try anything fancy */
+ if (tcp_in_recovery (tc))
+ return;
- /* Post retransmit update cwnd to ssthresh and account for the
- * three segments that have left the network and should've been
- * buffered at the receiver */
- tc->cwnd = tc->ssthresh + TCP_DUPACK_THRESHOLD * tc->snd_mss;
+ /* Remove retransmitted bytes that have been delivered */
+ if (tc->sack_sb.last_bytes_delivered
+ && seq_gt (tc->sack_sb.high_rxt, tc->snd_una))
+ {
+ /* If we have sacks and we haven't gotten an ack beyond high_rxt,
+ * remove sacked bytes delivered */
+ tc->snd_rxt_bytes -= tc->sack_sb.last_bytes_delivered;
}
- else if (tc->rcv_dupacks > TCP_DUPACK_THRESHOLD)
+ else
{
- ASSERT (tcp_in_fastrecovery (tc));
-
- tc->cc_algo->rcv_cong_ack (tc, TCP_CC_DUPACK);
+ /* Either all retransmitted holes have been acked, or we're
+ * "in the blind" and retransmitting segment by segment */
+ tc->snd_rxt_bytes = 0;
}
+
+ tc->cc_algo->rcv_cong_ack (tc, TCP_CC_PARTIALACK);
+
+ /*
+ * Since this was a partial ack, try to retransmit some more data
+ */
+ tcp_fast_retransmit (tc);
}
void
@@ -862,14 +1144,18 @@ tcp_cc_init (tcp_connection_t * tc)
tc->cc_algo->init (tc);
}
+/**
+ * Process incoming ACK
+ */
static int
tcp_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b,
tcp_header_t * th, u32 * next, u32 * error)
{
- u32 new_snd_wnd;
+ u32 prev_snd_wnd, prev_snd_una;
+ u8 is_dack;
/* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
- if (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt))
+ if (PREDICT_FALSE (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt)))
{
/* If we have outstanding data and this is within the window, accept it,
* probably retransmit has timed out. Otherwise ACK segment and then
@@ -892,7 +1178,7 @@ tcp_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b,
}
/* If old ACK, probably it's an old dupack */
- if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
+ if (PREDICT_FALSE (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una)))
{
*error = TCP_ERROR_ACK_OLD;
TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 1,
@@ -900,54 +1186,50 @@ tcp_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b,
if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
{
TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc);
- tcp_cc_rcv_dupack (tc, vnet_buffer (b)->tcp.ack_number);
+ tcp_cc_handle_event (tc, 1);
}
/* Don't drop yet */
return 0;
}
- if (tcp_opts_sack_permitted (&tc->opt))
- tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
-
- new_snd_wnd = clib_net_to_host_u16 (th->window) << tc->snd_wscale;
-
- if (tcp_ack_is_dupack (tc, b, new_snd_wnd))
- {
- TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc, 1);
- tcp_cc_rcv_dupack (tc, vnet_buffer (b)->tcp.ack_number);
- *error = TCP_ERROR_ACK_DUP;
- return -1;
- }
-
/*
- * Valid ACK
+ * Looks okay, process feedback
*/
- tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
- tc->snd_una = vnet_buffer (b)->tcp.ack_number + tc->sack_sb.snd_una_adv;
+ TCP_EVT_DBG (TCP_EVT_ACK_RCVD, tc);
+
+ if (tcp_opts_sack_permitted (&tc->rcv_opts))
+ tcp_rcv_sacks (tc, vnet_buffer (b)->tcp.ack_number);
- /* Dequeue ACKed data and update RTT */
- tcp_dequeue_acked (tc, vnet_buffer (b)->tcp.ack_number);
+ prev_snd_wnd = tc->snd_wnd;
+ prev_snd_una = tc->snd_una;
tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
- vnet_buffer (b)->tcp.ack_number, new_snd_wnd);
+ vnet_buffer (b)->tcp.ack_number,
+ clib_net_to_host_u16 (th->window) << tc->snd_wscale);
+ tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
+ tc->snd_una = vnet_buffer (b)->tcp.ack_number + tc->sack_sb.snd_una_adv;
+ tcp_validate_txf_size (tc, tc->bytes_acked);
- /* If some of our sent bytes have been acked, update cc and retransmit
- * timer. */
if (tc->bytes_acked)
- {
- TCP_EVT_DBG (TCP_EVT_ACK_RCVD, tc);
+ tcp_dequeue_acked (tc, vnet_buffer (b)->tcp.ack_number);
- /* Updates congestion control (slow start/congestion avoidance) */
- tcp_cc_rcv_ack (tc, b);
+ /*
+ * Check if we have congestion event
+ */
- /* If everything has been acked, stop retransmit timer
- * otherwise update. */
- if (tc->snd_una == tc->snd_una_max)
- tcp_retransmit_timer_reset (tc);
- else
- tcp_retransmit_timer_update (tc);
+ if (tcp_ack_is_cc_event (tc, b, prev_snd_wnd, prev_snd_una, &is_dack))
+ {
+ tcp_cc_handle_event (tc, is_dack);
+ *error = TCP_ERROR_ACK_DUP;
+ TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc, 1);
+ return vnet_buffer (b)->tcp.data_len ? 0 : -1;
}
+ /*
+ * Update congestion control (slow start/congestion avoidance)
+ */
+ tcp_cc_update (tc, b);
+
return 0;
}
@@ -1059,7 +1341,7 @@ tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
}
/* Update SACK list if need be */
- if (tcp_opts_sack_permitted (&tc->opt))
+ if (tcp_opts_sack_permitted (&tc->rcv_opts))
{
/* Remove SACK blocks that have been delivered */
tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
@@ -1097,7 +1379,7 @@ tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, data_len);
/* Update SACK list if in use */
- if (tcp_opts_sack_permitted (&tc->opt))
+ if (tcp_opts_sack_permitted (&tc->rcv_opts))
{
ooo_segment_t *newest;
u32 start, end;
@@ -1294,7 +1576,6 @@ tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
u32 n_left_to_next;
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
-
while (n_left_from > 0 && n_left_to_next > 0)
{
u32 bi0;
@@ -1321,7 +1602,6 @@ tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
}
th0 = tcp_buffer_hdr (b0);
-
is_fin = (th0->flags & TCP_FLAG_FIN) != 0;
/* SYNs, FINs and data consume sequence numbers */
@@ -1387,7 +1667,6 @@ tcp46_established_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
errors = session_manager_flush_enqueue_events (my_thread_index);
tcp_established_inc_counter (vm, is_ip4, TCP_ERROR_EVENT_FIFO_FULL, errors);
-
return from_frame->n_vectors;
}
@@ -1582,17 +1861,17 @@ tcp46_syn_sent_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
new_tc0->irs = seq0;
/* Parse options */
- if (tcp_options_parse (tcp0, &new_tc0->opt))
+ if (tcp_options_parse (tcp0, &new_tc0->rcv_opts))
goto drop;
- if (tcp_opts_tstamp (&new_tc0->opt))
+ if (tcp_opts_tstamp (&new_tc0->rcv_opts))
{
- new_tc0->tsval_recent = new_tc0->opt.tsval;
+ new_tc0->tsval_recent = new_tc0->rcv_opts.tsval;
new_tc0->tsval_recent_age = tcp_time_now ();
}
- if (tcp_opts_wscale (&new_tc0->opt))
- new_tc0->snd_wscale = new_tc0->opt.wscale;
+ if (tcp_opts_wscale (&new_tc0->rcv_opts))
+ new_tc0->snd_wscale = new_tc0->rcv_opts.wscale;
/* No scaling */
new_tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window);
@@ -1845,7 +2124,7 @@ tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
/* Initialize session variables */
tc0->snd_una = vnet_buffer (b0)->tcp.ack_number;
tc0->snd_wnd = clib_net_to_host_u16 (tcp0->window)
- << tc0->opt.wscale;
+ << tc0->rcv_opts.wscale;
tc0->snd_wl1 = vnet_buffer (b0)->tcp.seq_number;
tc0->snd_wl2 = vnet_buffer (b0)->tcp.ack_number;
@@ -1903,13 +2182,21 @@ tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
break;
case TCP_STATE_LAST_ACK:
- /* The only thing that can arrive in this state is an
+ /* The only thing that [should] arrive in this state is an
* acknowledgment of our FIN. If our FIN is now acknowledged,
* delete the TCB, enter the CLOSED state, and return. */
if (!tcp_rcv_ack_is_acceptable (tc0, b0))
goto drop;
+ /* Apparently our FIN was lost */
+ if (tcp_fin (tcp0))
+ {
+ /* Don't "make" fin since that increments snd_nxt */
+ tcp_send_fin (tc0);
+ goto drop;
+ }
+
tc0->state = TCP_STATE_CLOSED;
/* Don't delete the connection/session yet. Instead, wait a
@@ -1929,8 +2216,15 @@ tcp46_rcv_process_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
* retransmission of the remote FIN. Acknowledge it, and restart
* the 2 MSL timeout. */
- /* TODO */
+ if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
+ goto drop;
+
+ tcp_make_ack (tc0, b0);
+ tcp_timer_reset (tc0, TCP_TIMER_WAITCLOSE);
+ tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
+
goto drop;
+
break;
default:
ASSERT (0);
@@ -2194,7 +2488,7 @@ tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
goto drop;
}
- if (tcp_options_parse (th0, &child0->opt))
+ if (tcp_options_parse (th0, &child0->rcv_opts))
{
goto drop;
}
@@ -2205,14 +2499,14 @@ tcp46_listen_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
/* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
* segments are used to initialize PAWS. */
- if (tcp_opts_tstamp (&child0->opt))
+ if (tcp_opts_tstamp (&child0->rcv_opts))
{
- child0->tsval_recent = child0->opt.tsval;
+ child0->tsval_recent = child0->rcv_opts.tsval;
child0->tsval_recent_age = tcp_time_now ();
}
- if (tcp_opts_wscale (&child0->opt))
- child0->snd_wscale = child0->opt.wscale;
+ if (tcp_opts_wscale (&child0->rcv_opts))
+ child0->snd_wscale = child0->rcv_opts.wscale;
/* No scaling */
child0->snd_wnd = clib_net_to_host_u16 (th0->window);
@@ -2477,7 +2771,6 @@ tcp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
vlib_add_trace (vm, node, b0, sizeof (*t0));
tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
}
-
vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
n_left_to_next, bi0, next0);
}
@@ -2600,7 +2893,13 @@ do { \
_(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
TCP_ERROR_NONE);
_(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(LAST_ACK, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(LAST_ACK, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
+ TCP_ERROR_NONE);
_(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(TIME_WAIT, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(TIME_WAIT, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
+ TCP_ERROR_NONE);
_(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
_(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
#undef _
diff --git a/src/vnet/tcp/tcp_newreno.c b/src/vnet/tcp/tcp_newreno.c
index 3525f4e5..c66250e4 100644
--- a/src/vnet/tcp/tcp_newreno.c
+++ b/src/vnet/tcp/tcp_newreno.c
@@ -51,9 +51,23 @@ newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type)
}
else if (ack_type == TCP_CC_PARTIALACK)
{
- tc->cwnd -= tc->bytes_acked;
- if (tc->bytes_acked > tc->snd_mss)
- tc->bytes_acked += tc->snd_mss;
+ /* RFC 6582 Sec. 3.2 */
+ if (!tcp_opts_sack_permitted (&tc->rcv_opts))
+ {
+ /* Deflate the congestion window by the amount of new data
+ * acknowledged by the Cumulative Acknowledgment field.
+ * If the partial ACK acknowledges at least one SMSS of new data,
+ * then add back SMSS bytes to the congestion window. This
+ * artificially inflates the congestion window in order to reflect
+ * the additional segment that has left the network. This "partial
+ * window deflation" attempts to ensure that, when fast recovery
+ * eventually ends, approximately ssthresh amount of data will be
+ * outstanding in the network.*/
+ tc->cwnd = (tc->cwnd > tc->bytes_acked) ?
+ tc->cwnd - tc->bytes_acked : 0;
+ if (tc->bytes_acked > tc->snd_mss)
+ tc->cwnd += tc->snd_mss;
+ }
}
}
diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c
index 49fd6bef..47c94e6d 100644
--- a/src/vnet/tcp/tcp_output.c
+++ b/src/vnet/tcp/tcp_output.c
@@ -136,10 +136,10 @@ tcp_update_rcv_wnd (tcp_connection_t * tc)
* Figure out how much space we have available
*/
available_space = stream_session_max_rx_enqueue (&tc->connection);
- max_fifo = stream_session_fifo_size (&tc->connection);
+ max_fifo = stream_session_rx_fifo_size (&tc->connection);
- ASSERT (tc->opt.mss < max_fifo);
- if (available_space < tc->opt.mss && available_space < max_fifo >> 3)
+ ASSERT (tc->rcv_opts.mss < max_fifo);
+ if (available_space < tc->rcv_opts.mss && available_space < max_fifo >> 3)
available_space = 0;
/*
@@ -276,8 +276,11 @@ tcp_make_syn_options (tcp_options_t * opts, u8 wnd_scale)
opts->tsecr = 0;
len += TCP_OPTION_LEN_TIMESTAMP;
- opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
- len += TCP_OPTION_LEN_SACK_PERMITTED;
+ if (TCP_USE_SACKS)
+ {
+ opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
+ len += TCP_OPTION_LEN_SACK_PERMITTED;
+ }
/* Align to needed boundary */
len += (TCP_OPTS_ALIGN - len % TCP_OPTS_ALIGN) % TCP_OPTS_ALIGN;
@@ -293,14 +296,14 @@ tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
opts->mss = tc->mss;
len += TCP_OPTION_LEN_MSS;
- if (tcp_opts_wscale (&tc->opt))
+ if (tcp_opts_wscale (&tc->rcv_opts))
{
opts->flags |= TCP_OPTS_FLAG_WSCALE;
opts->wscale = tc->rcv_wscale;
len += TCP_OPTION_LEN_WINDOW_SCALE;
}
- if (tcp_opts_tstamp (&tc->opt))
+ if (tcp_opts_tstamp (&tc->rcv_opts))
{
opts->flags |= TCP_OPTS_FLAG_TSTAMP;
opts->tsval = tcp_time_now ();
@@ -308,7 +311,7 @@ tcp_make_synack_options (tcp_connection_t * tc, tcp_options_t * opts)
len += TCP_OPTION_LEN_TIMESTAMP;
}
- if (tcp_opts_sack_permitted (&tc->opt))
+ if (tcp_opts_sack_permitted (&tc->rcv_opts))
{
opts->flags |= TCP_OPTS_FLAG_SACK_PERMITTED;
len += TCP_OPTION_LEN_SACK_PERMITTED;
@@ -326,14 +329,14 @@ tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
opts->flags = 0;
- if (tcp_opts_tstamp (&tc->opt))
+ if (tcp_opts_tstamp (&tc->rcv_opts))
{
opts->flags |= TCP_OPTS_FLAG_TSTAMP;
opts->tsval = tcp_time_now ();
opts->tsecr = tc->tsval_recent;
len += TCP_OPTION_LEN_TIMESTAMP;
}
- if (tcp_opts_sack_permitted (&tc->opt))
+ if (tcp_opts_sack_permitted (&tc->rcv_opts))
{
if (vec_len (tc->snd_sacks))
{
@@ -395,7 +398,7 @@ tcp_update_snd_mss (tcp_connection_t * tc)
tcp_make_options (tc, &tc->snd_opts, TCP_STATE_ESTABLISHED);
/* XXX check if MTU has been updated */
- tc->snd_mss = clib_min (tc->mss, tc->opt.mss) - tc->snd_opts_len;
+ tc->snd_mss = clib_min (tc->mss, tc->rcv_opts.mss) - tc->snd_opts_len;
ASSERT (tc->snd_mss > 0);
}
@@ -406,21 +409,21 @@ tcp_init_mss (tcp_connection_t * tc)
tcp_update_rcv_mss (tc);
/* TODO cache mss and consider PMTU discovery */
- tc->snd_mss = clib_min (tc->opt.mss, tc->mss);
+ tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss);
if (tc->snd_mss < 45)
{
clib_warning ("snd mss is 0");
/* Assume that at least the min default mss works */
tc->snd_mss = default_min_mss;
- tc->opt.mss = default_min_mss;
+ tc->rcv_opts.mss = default_min_mss;
}
/* We should have enough space for 40 bytes of options */
ASSERT (tc->snd_mss > 45);
/* If we use timestamp option, account for it */
- if (tcp_opts_tstamp (&tc->opt))
+ if (tcp_opts_tstamp (&tc->rcv_opts))
tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP;
}
@@ -879,6 +882,7 @@ tcp_send_fin (tcp_connection_t * tc)
tcp_make_fin (tc, b);
tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
tc->flags |= TCP_CONN_FINSNT;
+ tcp_retransmit_timer_force_update (tc);
TCP_EVT_DBG (TCP_EVT_FIN_SENT, tc);
}
@@ -919,10 +923,7 @@ tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b,
if (compute_opts)
tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
- /* Write pre-computed options */
tcp_hdr_opts_len = tc->snd_opts_len + sizeof (tcp_header_t);
-
- /* Get rcv window to advertise */
advertise_wnd = tcp_window_to_advertise (tc, next_state);
flags = tcp_make_state_flags (next_state);
@@ -930,26 +931,25 @@ tcp_push_hdr_i (tcp_connection_t * tc, vlib_buffer_t * b,
th = vlib_buffer_push_tcp (b, tc->c_lcl_port, tc->c_rmt_port, tc->snd_nxt,
tc->rcv_nxt, tcp_hdr_opts_len, flags,
advertise_wnd);
-
opts_write_len = tcp_options_write ((u8 *) (th + 1), &tc->snd_opts);
ASSERT (opts_write_len == tc->snd_opts_len);
-
- /* Tag the buffer with the connection index */
vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
+ /*
+ * Update connection variables
+ */
+
tc->snd_nxt += data_len;
tc->rcv_las = tc->rcv_nxt;
/* TODO this is updated in output as well ... */
- if (tc->snd_nxt > tc->snd_una_max)
- tc->snd_una_max = tc->snd_nxt;
-
- if (tc->rtt_ts == 0)
+ if (seq_gt (tc->snd_nxt, tc->snd_una_max))
{
- tc->rtt_ts = tcp_time_now ();
- tc->rtt_seq = tc->snd_nxt;
+ tc->snd_una_max = tc->snd_nxt;
+ tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
}
+
TCP_EVT_DBG (TCP_EVT_PKTIZE, tc);
}
@@ -987,13 +987,14 @@ tcp_timer_delack_handler (u32 index)
*
* @return the number of bytes in the segment or 0 if there's nothing to
* retransmit
- * */
+ */
u32
tcp_prepare_retransmit_segment (tcp_connection_t * tc, vlib_buffer_t * b,
u32 offset, u32 max_bytes)
{
vlib_main_t *vm = vlib_get_main ();
- u32 n_bytes = 0;
+ int n_bytes = 0;
+ u32 start;
tcp_reuse_buffer (vm, b);
@@ -1001,15 +1002,16 @@ tcp_prepare_retransmit_segment (tcp_connection_t * tc, vlib_buffer_t * b,
ASSERT (max_bytes != 0);
max_bytes = clib_min (tc->snd_mss, max_bytes);
+ start = tc->snd_una + offset;
/* Start is beyond snd_congestion */
- if (seq_geq (tc->snd_una + offset, tc->snd_congestion))
+ if (seq_geq (start, tc->snd_congestion))
goto done;
/* Don't overshoot snd_congestion */
- if (seq_gt (tc->snd_nxt + max_bytes, tc->snd_congestion))
+ if (seq_gt (start + max_bytes, tc->snd_congestion))
{
- max_bytes = tc->snd_congestion - tc->snd_nxt;
+ max_bytes = tc->snd_congestion - start;
if (max_bytes == 0)
goto done;
}
@@ -1021,15 +1023,12 @@ tcp_prepare_retransmit_segment (tcp_connection_t * tc, vlib_buffer_t * b,
n_bytes = stream_session_peek_bytes (&tc->connection,
vlib_buffer_get_current (b), offset,
max_bytes);
- ASSERT (n_bytes != 0);
+ ASSERT (n_bytes > 0);
b->current_length = n_bytes;
tcp_push_hdr_i (tc, b, tc->state, 0);
- /* Don't count multiple retransmits of the same segment */
- if (tc->rto_boff > 1)
- goto done;
-
- tc->rtx_bytes += n_bytes;
+ if (tcp_in_fastrecovery (tc))
+ tc->snd_rxt_bytes += n_bytes;
done:
TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes);
@@ -1042,18 +1041,15 @@ done:
static void
tcp_rtx_timeout_cc (tcp_connection_t * tc)
{
+ tc->prev_ssthresh = tc->ssthresh;
+ tc->prev_cwnd = tc->cwnd;
+
/* Cleanly recover cc (also clears up fast retransmit) */
if (tcp_in_fastrecovery (tc))
- {
- tcp_cc_recover (tc);
- }
- else
- {
- tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss);
- }
+ tcp_cc_fastrecovery_exit (tc);
/* Start again from the beginning */
-
+ tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss);
tc->cwnd = tcp_loss_wnd (tc);
tc->snd_congestion = tc->snd_una_max;
tcp_recovery_on (tc);
@@ -1081,18 +1077,31 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
/* Make sure timer handle is set to invalid */
tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
+ if (!tcp_in_recovery (tc) && tc->rto_boff > 0
+ && tc->state >= TCP_STATE_ESTABLISHED)
+ {
+ tc->rto_boff = 0;
+ tcp_update_rto (tc);
+ }
+
/* Increment RTO backoff (also equal to number of retries) */
tc->rto_boff += 1;
/* Go back to first un-acked byte */
tc->snd_nxt = tc->snd_una;
- /* Get buffer */
tcp_get_free_buffer_index (tm, &bi);
b = vlib_get_buffer (vm, bi);
if (tc->state >= TCP_STATE_ESTABLISHED)
{
+ /* Lost FIN, retransmit and return */
+ if (tc->flags & TCP_CONN_FINSNT)
+ {
+ tcp_send_fin (tc);
+ return;
+ }
+
/* First retransmit timeout */
if (tc->rto_boff == 1)
tcp_rtx_timeout_cc (tc);
@@ -1102,24 +1111,30 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 1);
- /* Send one segment. No fancy recovery for now! */
+ /* Send one segment */
n_bytes = tcp_prepare_retransmit_segment (tc, b, 0, tc->snd_mss);
+ /* TODO be less aggressive about this */
scoreboard_clear (&tc->sack_sb);
if (n_bytes == 0)
{
clib_warning ("could not retransmit anything");
+ clib_warning ("%U", format_tcp_connection, tc, 2);
+
/* Try again eventually */
tcp_retransmit_timer_set (tc);
+ ASSERT (0 || (tc->rto_boff > 1
+ && tc->snd_una == tc->snd_congestion));
return;
}
+
+ /* For first retransmit, record timestamp (Eifel detection RFC3522) */
+ if (tc->rto_boff == 1)
+ tc->snd_rxt_ts = tcp_time_now ();
}
- else
+ /* Retransmit for SYN/SYNACK */
+ else if (tc->state == TCP_STATE_SYN_RCVD || tc->state == TCP_STATE_SYN_SENT)
{
- /* Retransmit for SYN/SYNACK */
- ASSERT (tc->state == TCP_STATE_SYN_RCVD
- || tc->state == TCP_STATE_SYN_SENT);
-
/* Try without increasing RTO a number of times. If this fails,
* start growing RTO exponentially */
if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
@@ -1132,6 +1147,12 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
/* Account for the SYN */
tc->snd_nxt += 1;
}
+ else
+ {
+ ASSERT (tc->state == TCP_STATE_CLOSED);
+ clib_warning ("connection closed ...");
+ return;
+ }
if (!is_syn)
{
@@ -1180,7 +1201,8 @@ tcp_timer_persist_handler (u32 index)
u32 thread_index = vlib_get_thread_index ();
tcp_connection_t *tc;
vlib_buffer_t *b;
- u32 bi, n_bytes;
+ u32 bi, old_snd_nxt;
+ int n_bytes = 0;
tc = tcp_connection_get_if_valid (index, thread_index);
@@ -1202,13 +1224,15 @@ tcp_timer_persist_handler (u32 index)
/* Try to force the first unsent segment */
tcp_get_free_buffer_index (tm, &bi);
b = vlib_get_buffer (vm, bi);
+
+ tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
tc->snd_opts_len = tcp_make_options (tc, &tc->snd_opts, tc->state);
n_bytes = stream_session_peek_bytes (&tc->connection,
vlib_buffer_get_current (b),
tc->snd_una_max - tc->snd_una,
tc->snd_mss);
/* Nothing to send */
- if (n_bytes == 0)
+ if (n_bytes <= 0)
{
clib_warning ("persist found nothing to send");
tcp_return_buffer (tm);
@@ -1216,7 +1240,13 @@ tcp_timer_persist_handler (u32 index)
}
b->current_length = n_bytes;
+ ASSERT (tc->snd_nxt == tc->snd_una_max || tc->rto_boff > 1
+ || tcp_timer_is_active (tc, TCP_TIMER_RETRANSMIT));
+
+ /* Allow updating of snd_una_max but don't update snd_nxt */
+ old_snd_nxt = tc->snd_nxt;
tcp_push_hdr_i (tc, b, tc->state, 0);
+ tc->snd_nxt = old_snd_nxt;
tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
/* Re-enable persist timer */
@@ -1232,8 +1262,9 @@ tcp_retransmit_first_unacked (tcp_connection_t * tc)
tcp_main_t *tm = vnet_get_tcp_main ();
vlib_main_t *vm = vlib_get_main ();
vlib_buffer_t *b;
- u32 bi, n_bytes;
+ u32 bi, n_bytes, old_snd_nxt;
+ old_snd_nxt = tc->snd_nxt;
tc->snd_nxt = tc->snd_una;
/* Get buffer */
@@ -1244,75 +1275,117 @@ tcp_retransmit_first_unacked (tcp_connection_t * tc)
n_bytes = tcp_prepare_retransmit_segment (tc, b, 0, tc->snd_mss);
if (n_bytes == 0)
- goto done;
+ {
+ tcp_return_buffer (tm);
+ goto done;
+ }
tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
done:
- tc->snd_nxt = tc->snd_una_max;
+ tc->snd_nxt = old_snd_nxt;
}
-sack_scoreboard_hole_t *
-scoreboard_first_rtx_hole (sack_scoreboard_t * sb)
+/**
+ * Do fast retransmit with SACKs
+ */
+void
+tcp_fast_retransmit_sack (tcp_connection_t * tc)
{
- sack_scoreboard_hole_t *hole = 0;
-
-// hole = scoreboard_first_hole (&tc->sack_sb);
-// if (hole)
-// {
-//
-// offset = hole->start - tc->snd_una;
-// hole_size = hole->end - hole->start;
-//
-// ASSERT(hole_size);
-//
-// if (hole_size < max_bytes)
-// max_bytes = hole_size;
-// }
- return hole;
+ tcp_main_t *tm = vnet_get_tcp_main ();
+ vlib_main_t *vm = vlib_get_main ();
+ u32 n_written = 0, offset = 0, max_bytes;
+ vlib_buffer_t *b;
+ sack_scoreboard_hole_t *hole;
+ sack_scoreboard_t *sb;
+ u32 bi, old_snd_nxt;
+ int snd_space;
+ u8 snd_limited = 0, can_rescue = 0;
+
+ ASSERT (tcp_in_fastrecovery (tc));
+ TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
+
+ old_snd_nxt = tc->snd_nxt;
+ sb = &tc->sack_sb;
+ snd_space = tcp_available_snd_space (tc);
+
+ hole = scoreboard_get_hole (sb, sb->cur_rxt_hole);
+ while (hole && snd_space > 0)
+ {
+ tcp_get_free_buffer_index (tm, &bi);
+ b = vlib_get_buffer (vm, bi);
+
+ hole = scoreboard_next_rxt_hole (sb, hole,
+ tcp_fastrecovery_sent_1_smss (tc),
+ &can_rescue, &snd_limited);
+ if (!hole)
+ {
+ if (!can_rescue || !(seq_lt (sb->rescue_rxt, tc->snd_una)
+ || seq_gt (sb->rescue_rxt,
+ tc->snd_congestion)))
+ break;
+
+ /* If rescue rxt undefined or less than snd_una then one segment of
+ * up to SMSS octets that MUST include the highest outstanding
+ * unSACKed sequence number SHOULD be returned, and RescueRxt set to
+ * RecoveryPoint. HighRxt MUST NOT be updated.
+ */
+ max_bytes = clib_min (tc->snd_mss, snd_space);
+ offset = tc->snd_congestion - tc->snd_una - max_bytes;
+ sb->rescue_rxt = tc->snd_congestion;
+ tc->snd_nxt = tc->snd_una + offset;
+ tcp_prepare_retransmit_segment (tc, b, offset, max_bytes);
+ tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
+ break;
+ }
+
+ max_bytes = snd_limited ? tc->snd_mss : hole->end - sb->high_rxt;
+ offset = sb->high_rxt - tc->snd_una;
+ tc->snd_nxt = tc->snd_una + offset;
+ n_written = tcp_prepare_retransmit_segment (tc, b, offset, max_bytes);
+
+ /* Nothing left to retransmit */
+ if (n_written == 0)
+ {
+ tcp_return_buffer (tm);
+ break;
+ }
+
+ sb->high_rxt += n_written;
+ tcp_enqueue_to_output (vm, b, bi, tc->c_is_ip4);
+ snd_space -= n_written;
+ }
+
+ /* If window allows, send 1 SMSS of new data */
+ tc->snd_nxt = old_snd_nxt;
}
/**
- * Do fast retransmit.
+ * Fast retransmit without SACK info
*/
void
-tcp_fast_retransmit (tcp_connection_t * tc)
+tcp_fast_retransmit_no_sack (tcp_connection_t * tc)
{
tcp_main_t *tm = vnet_get_tcp_main ();
vlib_main_t *vm = vlib_get_main ();
- u32 bi;
+ u32 n_written = 0, offset = 0, bi, old_snd_nxt;
int snd_space;
- u32 n_written = 0, offset = 0;
vlib_buffer_t *b;
- u8 use_sacks = 0;
ASSERT (tcp_in_fastrecovery (tc));
+ TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
/* Start resending from first un-acked segment */
+ old_snd_nxt = tc->snd_nxt;
tc->snd_nxt = tc->snd_una;
-
snd_space = tcp_available_snd_space (tc);
- TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
-
- /* If we have SACKs use them */
- if (tcp_opts_sack_permitted (&tc->opt)
- && scoreboard_first_hole (&tc->sack_sb))
- use_sacks = 0;
while (snd_space > 0)
{
tcp_get_free_buffer_index (tm, &bi);
b = vlib_get_buffer (vm, bi);
- if (use_sacks)
- {
- scoreboard_first_rtx_hole (&tc->sack_sb);
- }
- else
- {
- offset += n_written;
- }
-
+ offset += n_written;
n_written = tcp_prepare_retransmit_segment (tc, b, offset, snd_space);
/* Nothing left to retransmit */
@@ -1326,9 +1399,21 @@ tcp_fast_retransmit (tcp_connection_t * tc)
snd_space -= n_written;
}
- /* If window allows, send 1 SMSS of new data */
- if (seq_lt (tc->snd_nxt, tc->snd_congestion))
- tc->snd_nxt = tc->snd_congestion;
+ /* Restore snd_nxt. If window allows, send 1 SMSS of new data */
+ tc->snd_nxt = old_snd_nxt;
+}
+
+/**
+ * Do fast retransmit
+ */
+void
+tcp_fast_retransmit (tcp_connection_t * tc)
+{
+ if (tcp_opts_sack_permitted (&tc->rcv_opts)
+ && scoreboard_first_hole (&tc->sack_sb))
+ tcp_fast_retransmit_sack (tc);
+ else
+ tcp_fast_retransmit_no_sack (tc);
}
always_inline u32
@@ -1544,6 +1629,12 @@ tcp_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
tc = (tcp_connection_t *) tconn;
tcp_push_hdr_i (tc, b, TCP_STATE_ESTABLISHED, 0);
+
+ if (tc->rtt_ts == 0)
+ {
+ tc->rtt_ts = tcp_time_now ();
+ tc->rtt_seq = tc->snd_nxt;
+ }
return 0;
}
diff --git a/src/vnet/tcp/tcp_test.c b/src/vnet/tcp/tcp_test.c
index 2af38484..3f8afa40 100644
--- a/src/vnet/tcp/tcp_test.c
+++ b/src/vnet/tcp/tcp_test.c
@@ -54,7 +54,7 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
tc->snd_una = 0;
tc->snd_una_max = 1000;
tc->snd_nxt = 1000;
- tc->opt.flags |= TCP_OPTS_FLAG_SACK;
+ tc->rcv_opts.flags |= TCP_OPTS_FLAG_SACK;
scoreboard_init (&tc->sack_sb);
for (i = 0; i < 1000 / 100; i++)
@@ -70,9 +70,9 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
for (i = 0; i < 1000 / 200; i++)
{
- vec_add1 (tc->opt.sacks, sacks[i * 2]);
+ vec_add1 (tc->rcv_opts.sacks, sacks[i * 2]);
}
- tc->opt.n_sack_blocks = vec_len (tc->opt.sacks);
+ tc->rcv_opts.n_sack_blocks = vec_len (tc->rcv_opts.sacks);
tcp_rcv_sacks (tc, 0);
if (verbose)
@@ -93,18 +93,17 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
TCP_TEST ((sb->snd_una_adv == 0), "snd_una_adv %u", sb->snd_una_adv);
TCP_TEST ((sb->last_sacked_bytes == 400),
"last sacked bytes %d", sb->last_sacked_bytes);
- TCP_TEST ((sb->max_byte_sacked == 900),
- "max byte sacked %u", sb->max_byte_sacked);
+ TCP_TEST ((sb->high_sacked == 900), "max byte sacked %u", sb->high_sacked);
/*
* Inject odd blocks
*/
- vec_reset_length (tc->opt.sacks);
+ vec_reset_length (tc->rcv_opts.sacks);
for (i = 0; i < 1000 / 200; i++)
{
- vec_add1 (tc->opt.sacks, sacks[i * 2 + 1]);
+ vec_add1 (tc->rcv_opts.sacks, sacks[i * 2 + 1]);
}
- tc->opt.n_sack_blocks = vec_len (tc->opt.sacks);
+ tc->rcv_opts.n_sack_blocks = vec_len (tc->rcv_opts.sacks);
tcp_rcv_sacks (tc, 0);
if (verbose)
@@ -118,8 +117,7 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
"first hole start %u end %u", hole->start, hole->end);
TCP_TEST ((sb->sacked_bytes == 900), "sacked bytes %d", sb->sacked_bytes);
TCP_TEST ((sb->snd_una_adv == 0), "snd_una_adv %u", sb->snd_una_adv);
- TCP_TEST ((sb->max_byte_sacked == 1000),
- "max sacked byte %u", sb->max_byte_sacked);
+ TCP_TEST ((sb->high_sacked == 1000), "max sacked byte %u", sb->high_sacked);
TCP_TEST ((sb->last_sacked_bytes == 500),
"last sacked bytes %d", sb->last_sacked_bytes);
@@ -135,8 +133,7 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
"scoreboard has %d elements", pool_elts (sb->holes));
TCP_TEST ((sb->snd_una_adv == 900),
"snd_una_adv after ack %u", sb->snd_una_adv);
- TCP_TEST ((sb->max_byte_sacked == 1000),
- "max sacked byte %u", sb->max_byte_sacked);
+ TCP_TEST ((sb->high_sacked == 1000), "max sacked byte %u", sb->high_sacked);
TCP_TEST ((sb->sacked_bytes == 0), "sacked bytes %d", sb->sacked_bytes);
TCP_TEST ((sb->last_sacked_bytes == 0),
"last sacked bytes %d", sb->last_sacked_bytes);
@@ -145,11 +142,11 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
* Add new block
*/
- vec_reset_length (tc->opt.sacks);
+ vec_reset_length (tc->rcv_opts.sacks);
block.start = 1200;
block.end = 1300;
- vec_add1 (tc->opt.sacks, block);
+ vec_add1 (tc->rcv_opts.sacks, block);
if (verbose)
vlib_cli_output (vm, "add [1200, 1300]:\n%U", format_tcp_scoreboard, sb);
@@ -171,8 +168,7 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
"first hole start %u end %u", hole->start, hole->end);
TCP_TEST ((sb->snd_una_adv == 0),
"snd_una_adv after ack %u", sb->snd_una_adv);
- TCP_TEST ((sb->max_byte_sacked == 1300),
- "max sacked byte %u", sb->max_byte_sacked);
+ TCP_TEST ((sb->high_sacked == 1300), "max sacked byte %u", sb->high_sacked);
hole = scoreboard_last_hole (sb);
TCP_TEST ((hole->start == 1300 && hole->end == 1500),
"last hole start %u end %u", hole->start, hole->end);
@@ -182,7 +178,7 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
* Ack first hole
*/
- vec_reset_length (tc->opt.sacks);
+ vec_reset_length (tc->rcv_opts.sacks);
tcp_rcv_sacks (tc, 1200);
if (verbose)
@@ -196,8 +192,16 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
"scoreboard has %d elements", pool_elts (sb->holes));
/*
- * Remove all
+ * Add some more blocks and then remove all
*/
+ vec_reset_length (tc->rcv_opts.sacks);
+ for (i = 0; i < 5; i++)
+ {
+ block.start = i * 100 + 1200;
+ block.end = (i + 1) * 100 + 1200;
+ vec_add1 (tc->rcv_opts.sacks, block);
+ }
+ tcp_rcv_sacks (tc, 1900);
scoreboard_clear (sb);
if (verbose)
@@ -205,6 +209,9 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
TCP_TEST ((pool_elts (sb->holes) == 0),
"number of holes %d", pool_elts (sb->holes));
+ TCP_TEST ((sb->head == TCP_INVALID_SACK_HOLE_INDEX), "head %u", sb->head);
+ TCP_TEST ((sb->tail == TCP_INVALID_SACK_HOLE_INDEX), "tail %u", sb->tail);
+
/*
* Re-inject odd blocks and ack them all
*/
@@ -214,9 +221,9 @@ tcp_test_sack_rx (vlib_main_t * vm, unformat_input_t * input)
tc->snd_nxt = 1000;
for (i = 0; i < 5; i++)
{
- vec_add1 (tc->opt.sacks, sacks[i * 2 + 1]);
+ vec_add1 (tc->rcv_opts.sacks, sacks[i * 2 + 1]);
}
- tc->opt.n_sack_blocks = vec_len (tc->opt.sacks);
+ tc->rcv_opts.n_sack_blocks = vec_len (tc->rcv_opts.sacks);
tcp_rcv_sacks (tc, 0);
if (verbose)
vlib_cli_output (vm, "sb added odd blocks and ack [0, 950]:\n%U",
@@ -740,6 +747,10 @@ tcp_test_fifo1 (vlib_main_t * vm, unformat_input_t * input)
TCP_TEST (0, "[%d] peeked %u expected %u", j, data_buf[j], data[j]);
}
+ /* Try to peek beyond the data */
+ rv = svm_fifo_peek (f, svm_fifo_max_dequeue (f), vec_len (data), data_buf);
+ TCP_TEST ((rv == 0), "peeked %u expected 0", rv);
+
vec_free (data_buf);
svm_fifo_free (f);
vec_free (test_data);
@@ -1239,7 +1250,7 @@ tcp_test_session (vlib_main_t * vm, unformat_input_t * input)
tc0->c_thread_index = 0;
tc0->c_lcl_ip4.as_u32 = local.as_u32;
tc0->c_rmt_ip4.as_u32 = remote.as_u32;
- tc0->opt.mss = 1450;
+ tc0->rcv_opts.mss = 1450;
tcp_connection_init_vars (tc0);
TCP_EVT_DBG (TCP_EVT_OPEN, tc0);