sergiotarxz/nuttx
sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Networking: Fix another deadlock condition. tcp_write_buffer_alloc() calls sem_wait() with network locked. That worked if CONFIG_NET_NOINTS was not defined because interrupts are automatically restored when the wait happens. But with CONFIG_NET_NOINTS=y, the wait blocks with the network locked -- bad style and also can lead to a deadlock condition

Browse Source
This commit is contained in:
Gregory Nutt 2015-01-28 11:56:11 -06:00
parent 0f3f033880
commit 371a9fd84c
4 changed files with 57 additions and 48 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
net/socket/send.c
View File

@ -152,8 +152,13 @@ ssize_t psock_send(FAR struct socket *psock, FAR const void *buf, size_t len,
default:
{
ret = ERROR;
/* EDESTADDRREQ. Signifies that the socket is not connection-mode
* and no peer address is set.
*/
ret = -EDESTADDRREQ;
}
break;
}
return ret;

2
net/tcp/tcp.h
View File

@ -1000,7 +1000,7 @@ void tcp_wrbuffer_initialize(void);
* None
*
* Assumptions:
* Called from user logic with interrupts enabled.
* Called from user logic with the network locked.
*
****************************************************************************/

91
net/tcp/tcp_send_buffered.c
View File

@ -918,6 +918,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
size_t len)
{
FAR struct tcp_conn_s *conn;
FAR struct tcp_wrbuffer_s *wrb;
net_lock_t save;
ssize_t result = 0;
int err;
@ -940,6 +941,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
/* Make sure that the IP address mapping is in the ARP table */
conn = (FAR struct tcp_conn_s *)psock->s_conn;
#ifdef CONFIG_NET_ARP_SEND
ret = arp_send(conn->u.ipv4.raddr);
if (ret < 0)
@ -958,10 +960,23 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_SEND);
save = net_lock();
if (len > 0)
{
/* Allocate a write buffer. Careful, the network will be momentarily
* unlocked here.
*/
save = net_lock();
wrb = tcp_wrbuffer_alloc();
if (!wrb)
{
/* A buffer allocation error occurred */
ndbg("ERROR: Failed to allocate write buffer\n");
err = ENOMEM;
goto errout_with_lock;
}
/* Allocate resources to receive a callback */
if (!psock->s_sndcb)
@ -976,61 +991,43 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
/* A buffer allocation error occurred */
ndbg("ERROR: Failed to allocate callback\n");
result = -ENOMEM;
err = ENOMEM;
goto errout_with_wrb;
}
else
{
FAR struct tcp_wrbuffer_s *wrb;
/* Set up the callback in the connection */
/* Set up the callback in the connection */
psock->s_sndcb->flags = (TCP_ACKDATA | TCP_REXMIT | TCP_POLL |
TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT);
psock->s_sndcb->priv = (void*)psock;
psock->s_sndcb->event = psock_send_interrupt;
psock->s_sndcb->flags = (TCP_ACKDATA | TCP_REXMIT | TCP_POLL |
TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT);
psock->s_sndcb->priv = (void*)psock;
psock->s_sndcb->event = psock_send_interrupt;
/* Allocate an write buffer */
/* Initialize the write buffer */
wrb = tcp_wrbuffer_alloc();
if (wrb)
{
/* Initialize the write buffer */
WRB_SEQNO(wrb) = (unsigned)-1;
WRB_NRTX(wrb) = 0;
WRB_COPYIN(wrb, (FAR uint8_t *)buf, len);
WRB_SEQNO(wrb) = (unsigned)-1;
WRB_NRTX(wrb) = 0;
WRB_COPYIN(wrb, (FAR uint8_t *)buf, len);
/* Dump I/O buffer chain */
/* Dump I/O buffer chain */
WRB_DUMP("I/O buffer chain", wrb, WRB_PKTLEN(wrb), 0);
WRB_DUMP("I/O buffer chain", wrb, WRB_PKTLEN(wrb), 0);
/* psock_send_interrupt() will send data in FIFO order from the
* conn->write_q
*/
/* psock_send_interrupt() will send data in FIFO order from the
* conn->write_q
*/
sq_addlast(&wrb->wb_node, &conn->write_q);
nvdbg("Queued WRB=%p pktlen=%u write_q(%p,%p)\n",
wrb, WRB_PKTLEN(wrb),
conn->write_q.head, conn->write_q.tail);
sq_addlast(&wrb->wb_node, &conn->write_q);
nvdbg("Queued WRB=%p pktlen=%u write_q(%p,%p)\n",
wrb, WRB_PKTLEN(wrb),
conn->write_q.head, conn->write_q.tail);
/* Notify the device driver of the availability of TX data */
/* Notify the device driver of the availability of TX data */
send_txnotify(psock, conn);
result = len;
}
/* A buffer allocation error occurred */
else
{
ndbg("ERROR: Failed to allocate write buffer\n");
result = -ENOMEM;
}
}
send_txnotify(psock, conn);
net_unlock(save);
result = len;
}
net_unlock(save);
/* Set the socket state to idle */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE);
@ -1059,6 +1056,12 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
return result;
errout_with_wrb:
tcp_wrbuffer_release(wrb);
errout_with_lock:
net_unlock(save);
errout:
set_errno(err);
return ERROR;

5
net/tcp/tcp_wrbuffer.c
View File

@ -54,6 +54,7 @@
#include <assert.h>
#include <debug.h>
#include <nuttx/net/net.h>
#include <nuttx/net/iob.h>
#include "tcp/tcp.h"
@ -132,7 +133,7 @@ void tcp_wrbuffer_initialize(void)
* None
*
* Assumptions:
* Called from user logic with interrupts enabled.
* Called from user logic with the network locked.
*
****************************************************************************/
@ -148,7 +149,7 @@ FAR struct tcp_wrbuffer_s *tcp_wrbuffer_alloc(void)
* buffer
*/
DEBUGVERIFY(sem_wait(&g_wrbuffer.sem));
DEBUGVERIFY(net_lockedwait(&g_wrbuffer.sem));
/* Now, we are guaranteed to have a write buffer structure reserved
* for us in the free list.