michaelh/zephyr
1
0
Fork 0
Code Releases Activity

Bluetooth: host: don't fragment ISO if len <= MTU

Browse source 
MTU doesn't count against the ISO and ISO data headers.

Then a config with CONFIG_BT_ISO_TX_MTU ==
CONFIG_BT_CTLR_ISO_TX_BUFFER_SIZE should not fragment SDUs over HCI.

Also set the TS_Flag bit if a timestamp is present.

Fixes #56749

Signed-off-by: Jonathan Rico <jonathan.rico@nordicsemi.no>
This commit is contained in:
Jonathan Rico 2023-04-24 11:05:06 +02:00 • committed by Carles Cufí
commit e460847b60
3 changed files with 67 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

59
subsys/bluetooth/host/conn.c
View file

@ -52,6 +52,8 @@ struct tx_meta {
* continuations).
*/
bool is_cont;
/* Indicates whether the ISO PDU contains a timestamp */
bool iso_has_ts;
};
BUILD_ASSERT(sizeof(struct tx_meta) == CONFIG_BT_CONN_TX_USER_DATA_SIZE,
@ -410,6 +412,24 @@ static struct bt_conn_tx *conn_tx_alloc(void)
return k_fifo_get(&free_tx, K_FOREVER);
}
int bt_conn_send_iso_cb(struct bt_conn *conn, struct net_buf *buf,
bt_conn_tx_cb_t cb, bool has_ts)
{
int err = bt_conn_send_cb(conn, buf, cb, NULL);
if (err) {
return err;
}
/* Necessary for setting the TS_Flag bit when we pop the buffer from the
* send queue.
* Size check for the user_data is already done in `bt_conn_send_cb`.
*/
tx_data(buf)->iso_has_ts = has_ts;
return 0;
}
int bt_conn_send_cb(struct bt_conn *conn, struct net_buf *buf,
bt_conn_tx_cb_t cb, void *user_data)
{
@ -419,7 +439,9 @@ int bt_conn_send_cb(struct bt_conn *conn, struct net_buf *buf,
user_data);
if (buf->user_data_size < CONFIG_BT_CONN_TX_USER_DATA_SIZE) {
LOG_ERR("not enough room in user_data");
LOG_ERR("not enough room in user_data %d < %d",
buf->user_data_size,
CONFIG_BT_CONN_TX_USER_DATA_SIZE);
return -EINVAL;
}
@ -493,6 +515,7 @@ static int send_acl(struct bt_conn *conn, struct net_buf *buf, uint8_t flags)
static int send_iso(struct bt_conn *conn, struct net_buf *buf, uint8_t flags)
{
struct bt_hci_iso_hdr *hdr;
bool ts;
switch (flags) {
case FRAG_START:
@ -512,8 +535,12 @@ static int send_iso(struct bt_conn *conn, struct net_buf *buf, uint8_t flags)
}
hdr = net_buf_push(buf, sizeof(*hdr));
hdr->handle = sys_cpu_to_le16(bt_iso_handle_pack(conn->handle, flags,
0));
ts = tx_data(buf)->iso_has_ts &&
(flags == BT_ISO_START || flags == BT_ISO_SINGLE);
hdr->handle = sys_cpu_to_le16(bt_iso_handle_pack(conn->handle, flags, ts));
hdr->len = sys_cpu_to_le16(buf->len - sizeof(*hdr));
bt_buf_set_type(buf, BT_BUF_ISO_OUT);
@ -621,6 +648,21 @@ fail:
return err;
}
static size_t iso_hdr_len(struct net_buf *buf, struct bt_conn *conn)
{
#if defined(CONFIG_BT_ISO)
if (conn->type == BT_CONN_TYPE_ISO) {
if (tx_data(buf)->iso_has_ts) {
return BT_HCI_ISO_TS_DATA_HDR_SIZE;
} else {
return BT_HCI_ISO_DATA_HDR_SIZE;
}
}
#endif
return 0;
}
static int send_frag(struct bt_conn *conn,
struct net_buf *buf, struct net_buf *frag,
uint8_t flags)
@ -633,7 +675,9 @@ static int send_frag(struct bt_conn *conn,
/* Add the data to the buffer */
if (frag) {
uint16_t frag_len = MIN(conn_mtu(conn), net_buf_tailroom(frag));
size_t iso_hdr = flags == FRAG_START ? iso_hdr_len(buf, conn) : 0;
uint16_t frag_len = MIN(conn_mtu(conn) + iso_hdr,
net_buf_tailroom(frag));
net_buf_add_mem(frag, buf->data, frag_len);
net_buf_pull(buf, frag_len);
@ -681,6 +725,11 @@ static struct net_buf *create_frag(struct bt_conn *conn, struct net_buf *buf)
return frag;
}
static bool fits_single_ctlr_buf(struct net_buf *buf, struct bt_conn *conn)
{
return buf->len - iso_hdr_len(buf, conn) <= conn_mtu(conn);
}
static int send_buf(struct bt_conn *conn, struct net_buf *buf)
{
struct net_buf *frag;
@ -690,7 +739,7 @@ static int send_buf(struct bt_conn *conn, struct net_buf *buf)
LOG_DBG("conn %p buf %p len %u", conn, buf, buf->len);
/* Send directly if the packet fits the ACL MTU */
if (buf->len <= conn_mtu(conn) && !tx_data(buf)->is_cont) {
if (fits_single_ctlr_buf(buf, conn) && !tx_data(buf)->is_cont) {
LOG_DBG("send single");
return send_frag(conn, buf, NULL, FRAG_SINGLE);
}

9
subsys/bluetooth/host/conn_internal.h
View file

@ -254,6 +254,15 @@ void bt_conn_recv(struct bt_conn *conn, struct net_buf *buf, uint8_t flags);
int bt_conn_send_cb(struct bt_conn *conn, struct net_buf *buf,
bt_conn_tx_cb_t cb, void *user_data);
/* Thin wrapper over `bt_conn_send_cb`
*
* Used to set the TS_Flag bit in `buf`'s metadata.
*
* Return values & buf ownership same as parent.
*/
int bt_conn_send_iso_cb(struct bt_conn *conn, struct net_buf *buf,
bt_conn_tx_cb_t cb, bool has_ts);
static inline int bt_conn_send(struct bt_conn *conn, struct net_buf *buf)
{
return bt_conn_send_cb(conn, buf, NULL, NULL);

5
subsys/bluetooth/host/iso.c
View file

@ -803,7 +803,10 @@ int bt_iso_chan_send(struct bt_iso_chan *chan, struct net_buf *buf,
BT_ISO_DATA_VALID));
}
return bt_conn_send_cb(iso_conn, buf, bt_iso_send_cb, NULL);
return bt_conn_send_iso_cb(iso_conn,
buf,
bt_iso_send_cb,
ts != BT_ISO_TIMESTAMP_NONE);
}
#if defined(CONFIG_BT_ISO_CENTRAL) || defined(CONFIG_BT_ISO_BROADCASTER)