summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJoel Sherrill <joel.sherrill@OARcorp.com>2000-08-01 15:23:59 +0000
committerJoel Sherrill <joel.sherrill@OARcorp.com>2000-08-01 15:23:59 +0000
commite6890ba1f56fc6614b9494331a9f45d65db31649 (patch)
tree250d49da47520a8921e58d148c1f0f258a39a266
parent161124420243063db5d5780afc583c82fa42f4c4 (diff)
downloadrtems-e6890ba1f56fc6614b9494331a9f45d65db31649.tar.bz2
Patch from Eric Norum <eric@cls.usask.ca> to avoid lockup under
the correct circumstances of DMA buffer size, serial line interrupts, and ethernet interrupts the termios osend routine would lock up waiting for the raw output buffer semaphore.
-rw-r--r--c/src/exec/libcsupport/src/termios.c18
-rw-r--r--c/src/lib/libc/termios.c18
-rw-r--r--cpukit/libcsupport/src/termios.c18
3 files changed, 27 insertions, 27 deletions
diff --git a/c/src/exec/libcsupport/src/termios.c b/c/src/exec/libcsupport/src/termios.c
index dea2608fa6..f70ed23c6a 100644
--- a/c/src/exec/libcsupport/src/termios.c
+++ b/c/src/exec/libcsupport/src/termios.c
@@ -126,7 +126,7 @@ struct rtems_termios_tty {
volatile unsigned int rawOutBufHead;
volatile unsigned int rawOutBufTail;
rtems_id rawOutBufSemaphore;
- enum {rob_idle, rob_busy, rob_wait } rawOutBufState;
+ volatile enum {rob_idle, rob_busy, rob_wait } rawOutBufState;
/*
* Callbacks to device-specific routines
@@ -219,7 +219,7 @@ rtems_termios_open (
sc = rtems_semaphore_create (
rtems_build_name ('T', 'R', 'x', c),
0,
- RTEMS_COUNTING_SEMAPHORE | RTEMS_PRIORITY,
+ RTEMS_SIMPLE_BINARY_SEMAPHORE | RTEMS_FIFO,
RTEMS_NO_PRIORITY,
&tty->rawOutBufSemaphore);
if (sc != RTEMS_SUCCESSFUL)
@@ -531,7 +531,7 @@ osend (const char *buf, int len, struct rtems_termios_tty *tty)
if (tty->rawOutBufState == rob_idle) {
/* check, whether XOFF has been received */
if (!(tty->flow_ctrl & FL_ORCVXOF)) {
- (*tty->device.write)(tty->minor,
+ (*tty->device.write)(tty->minor,
(char *)&tty->rawOutBuf[tty->rawOutBufTail],1);
}
else {
@@ -1101,8 +1101,10 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
else {
if (tty->rawOutBufState == rob_wait)
rtems_semaphore_release (tty->rawOutBufSemaphore);
- if ( tty->rawOutBufHead == tty->rawOutBufTail )
+ if ( tty->rawOutBufHead == tty->rawOutBufTail ) {
+ tty->rawOutBufState = rob_idle;
return 0;
+ }
newTail = (tty->rawOutBufTail + len) % RAW_OUTPUT_BUFFER_SIZE;
if (newTail == tty->rawOutBufHead) {
/*
@@ -1117,6 +1119,7 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
/* Buffer not empty, but output stops due to XOFF */
/* set flag, that output has been stopped */
tty->flow_ctrl |= FL_OSTOP;
+ tty->rawOutBufState = rob_busy;
nToSend = 0;
}
else {
@@ -1130,15 +1133,12 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
/* when flow control XON or XOF, don't send blocks of data */
/* to allow fast reaction on incoming flow ctrl and low latency*/
/* for outgoing flow control */
- if (tty->flow_ctrl & (FL_MDXON | FL_MDXOF)) {
+ if (tty->flow_ctrl & (FL_MDXON | FL_MDXOF))
nToSend = 1;
- }
- (*tty->device.write)(tty->minor, (char *)&tty->rawOutBuf[newTail], nToSend);
tty->rawOutBufState = rob_busy;
+ (*tty->device.write)(tty->minor, (char *)&tty->rawOutBuf[newTail], nToSend);
}
tty->rawOutBufTail = newTail;
}
return nToSend;
}
-
-
diff --git a/c/src/lib/libc/termios.c b/c/src/lib/libc/termios.c
index dea2608fa6..f70ed23c6a 100644
--- a/c/src/lib/libc/termios.c
+++ b/c/src/lib/libc/termios.c
@@ -126,7 +126,7 @@ struct rtems_termios_tty {
volatile unsigned int rawOutBufHead;
volatile unsigned int rawOutBufTail;
rtems_id rawOutBufSemaphore;
- enum {rob_idle, rob_busy, rob_wait } rawOutBufState;
+ volatile enum {rob_idle, rob_busy, rob_wait } rawOutBufState;
/*
* Callbacks to device-specific routines
@@ -219,7 +219,7 @@ rtems_termios_open (
sc = rtems_semaphore_create (
rtems_build_name ('T', 'R', 'x', c),
0,
- RTEMS_COUNTING_SEMAPHORE | RTEMS_PRIORITY,
+ RTEMS_SIMPLE_BINARY_SEMAPHORE | RTEMS_FIFO,
RTEMS_NO_PRIORITY,
&tty->rawOutBufSemaphore);
if (sc != RTEMS_SUCCESSFUL)
@@ -531,7 +531,7 @@ osend (const char *buf, int len, struct rtems_termios_tty *tty)
if (tty->rawOutBufState == rob_idle) {
/* check, whether XOFF has been received */
if (!(tty->flow_ctrl & FL_ORCVXOF)) {
- (*tty->device.write)(tty->minor,
+ (*tty->device.write)(tty->minor,
(char *)&tty->rawOutBuf[tty->rawOutBufTail],1);
}
else {
@@ -1101,8 +1101,10 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
else {
if (tty->rawOutBufState == rob_wait)
rtems_semaphore_release (tty->rawOutBufSemaphore);
- if ( tty->rawOutBufHead == tty->rawOutBufTail )
+ if ( tty->rawOutBufHead == tty->rawOutBufTail ) {
+ tty->rawOutBufState = rob_idle;
return 0;
+ }
newTail = (tty->rawOutBufTail + len) % RAW_OUTPUT_BUFFER_SIZE;
if (newTail == tty->rawOutBufHead) {
/*
@@ -1117,6 +1119,7 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
/* Buffer not empty, but output stops due to XOFF */
/* set flag, that output has been stopped */
tty->flow_ctrl |= FL_OSTOP;
+ tty->rawOutBufState = rob_busy;
nToSend = 0;
}
else {
@@ -1130,15 +1133,12 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
/* when flow control XON or XOF, don't send blocks of data */
/* to allow fast reaction on incoming flow ctrl and low latency*/
/* for outgoing flow control */
- if (tty->flow_ctrl & (FL_MDXON | FL_MDXOF)) {
+ if (tty->flow_ctrl & (FL_MDXON | FL_MDXOF))
nToSend = 1;
- }
- (*tty->device.write)(tty->minor, (char *)&tty->rawOutBuf[newTail], nToSend);
tty->rawOutBufState = rob_busy;
+ (*tty->device.write)(tty->minor, (char *)&tty->rawOutBuf[newTail], nToSend);
}
tty->rawOutBufTail = newTail;
}
return nToSend;
}
-
-
diff --git a/cpukit/libcsupport/src/termios.c b/cpukit/libcsupport/src/termios.c
index dea2608fa6..f70ed23c6a 100644
--- a/cpukit/libcsupport/src/termios.c
+++ b/cpukit/libcsupport/src/termios.c
@@ -126,7 +126,7 @@ struct rtems_termios_tty {
volatile unsigned int rawOutBufHead;
volatile unsigned int rawOutBufTail;
rtems_id rawOutBufSemaphore;
- enum {rob_idle, rob_busy, rob_wait } rawOutBufState;
+ volatile enum {rob_idle, rob_busy, rob_wait } rawOutBufState;
/*
* Callbacks to device-specific routines
@@ -219,7 +219,7 @@ rtems_termios_open (
sc = rtems_semaphore_create (
rtems_build_name ('T', 'R', 'x', c),
0,
- RTEMS_COUNTING_SEMAPHORE | RTEMS_PRIORITY,
+ RTEMS_SIMPLE_BINARY_SEMAPHORE | RTEMS_FIFO,
RTEMS_NO_PRIORITY,
&tty->rawOutBufSemaphore);
if (sc != RTEMS_SUCCESSFUL)
@@ -531,7 +531,7 @@ osend (const char *buf, int len, struct rtems_termios_tty *tty)
if (tty->rawOutBufState == rob_idle) {
/* check, whether XOFF has been received */
if (!(tty->flow_ctrl & FL_ORCVXOF)) {
- (*tty->device.write)(tty->minor,
+ (*tty->device.write)(tty->minor,
(char *)&tty->rawOutBuf[tty->rawOutBufTail],1);
}
else {
@@ -1101,8 +1101,10 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
else {
if (tty->rawOutBufState == rob_wait)
rtems_semaphore_release (tty->rawOutBufSemaphore);
- if ( tty->rawOutBufHead == tty->rawOutBufTail )
+ if ( tty->rawOutBufHead == tty->rawOutBufTail ) {
+ tty->rawOutBufState = rob_idle;
return 0;
+ }
newTail = (tty->rawOutBufTail + len) % RAW_OUTPUT_BUFFER_SIZE;
if (newTail == tty->rawOutBufHead) {
/*
@@ -1117,6 +1119,7 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
/* Buffer not empty, but output stops due to XOFF */
/* set flag, that output has been stopped */
tty->flow_ctrl |= FL_OSTOP;
+ tty->rawOutBufState = rob_busy;
nToSend = 0;
}
else {
@@ -1130,15 +1133,12 @@ rtems_termios_dequeue_characters (void *ttyp, int len)
/* when flow control XON or XOF, don't send blocks of data */
/* to allow fast reaction on incoming flow ctrl and low latency*/
/* for outgoing flow control */
- if (tty->flow_ctrl & (FL_MDXON | FL_MDXOF)) {
+ if (tty->flow_ctrl & (FL_MDXON | FL_MDXOF))
nToSend = 1;
- }
- (*tty->device.write)(tty->minor, (char *)&tty->rawOutBuf[newTail], nToSend);
tty->rawOutBufState = rob_busy;
+ (*tty->device.write)(tty->minor, (char *)&tty->rawOutBuf[newTail], nToSend);
}
tty->rawOutBufTail = newTail;
}
return nToSend;
}
-
-