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Diffstat (limited to 'usr/src/uts/sun4v/io/ds.c')
-rw-r--r--usr/src/uts/sun4v/io/ds.c114
1 files changed, 72 insertions, 42 deletions
diff --git a/usr/src/uts/sun4v/io/ds.c b/usr/src/uts/sun4v/io/ds.c
index 1b269ad276..2a8aea01dc 100644
--- a/usr/src/uts/sun4v/io/ds.c
+++ b/usr/src/uts/sun4v/io/ds.c
@@ -121,6 +121,15 @@ static boolean_t ds_enabled; /* enable/disable taskq processing */
#define DS_DISPATCH(fn, arg) taskq_dispatch(ds_taskq, fn, arg, TQ_SLEEP)
/*
+ * Retry count and delay for LDC reads and writes
+ */
+#define DS_DEFAULT_RETRIES 10000 /* number of times to retry */
+#define DS_DEFAULT_DELAY 1000 /* usecs to wait between retries */
+
+static int ds_retries = DS_DEFAULT_RETRIES;
+static clock_t ds_delay = DS_DEFAULT_DELAY;
+
+/*
* Supported versions of the DS message protocol
*
* The version array must be sorted in order from the highest
@@ -205,22 +214,24 @@ static ds_log_entry_t ds_log_entry_pool[DS_LOG_NPOOL];
#define DS_DBG_FLAG_LDC 0x1
#define DS_DBG_FLAG_LOG 0x2
+#define DS_DBG_FLAG_MSG 0x4
#define DS_DBG_FLAG_ALL 0xf
#define DS_DBG if (ds_debug) printf
#define DS_DBG_LDC if (ds_debug & DS_DBG_FLAG_LDC) printf
#define DS_DBG_LOG if (ds_debug & DS_DBG_FLAG_LOG) printf
-#define DS_DUMP_LDC_MSG(buf, len) ds_dump_ldc_msg(buf, len)
+#define DS_DBG_MSG if (ds_debug & DS_DBG_FLAG_MSG) printf
+#define DS_DUMP_MSG(buf, len) ds_dump_msg(buf, len)
uint_t ds_debug = 0;
-static void ds_dump_ldc_msg(void *buf, size_t len);
+static void ds_dump_msg(void *buf, size_t len);
#else /* DEBUG */
#define DS_DBG _NOTE(CONSTCOND) if (0) printf
#define DS_DBG_LDC DS_DBG
#define DS_DBG_LOG DS_DBG
-#define DS_DUMP_LDC_MSG(buf, len)
+#define DS_DUMP_MSG(buf, len)
#endif /* DEBUG */
@@ -236,7 +247,7 @@ static int ds_ldc_fini(ds_port_t *port);
/* event processing functions */
static uint_t ds_ldc_cb(uint64_t event, caddr_t arg);
static void ds_dispatch_event(void *arg);
-static int ds_recv_msg(ldc_handle_t ldc_hdl, caddr_t msgp, size_t *sizep);
+static int ds_recv_msg(ds_port_t *port, caddr_t msgp, size_t *sizep);
static void ds_handle_recv(void *arg);
/* message sending functions */
@@ -764,42 +775,64 @@ done:
* in the size parameter.
*/
static int
-ds_recv_msg(ldc_handle_t ldc_hdl, caddr_t msgp, size_t *sizep)
+ds_recv_msg(ds_port_t *port, caddr_t msgp, size_t *sizep)
{
int rv = 0;
- size_t msglen = *sizep;
- size_t amt_left = msglen;
- int loopcnt = 0;
+ size_t bytes_req = *sizep;
+ size_t bytes_left = bytes_req;
+ size_t nbytes;
+ int retry_count = 0;
*sizep = 0;
- while (msglen > 0) {
- if ((rv = ldc_read(ldc_hdl, msgp, &amt_left)) != 0) {
- if ((rv == EAGAIN) && (loopcnt++ < 1000)) {
- /*
- * Try again, but don't try for more than
- * one second. Something is wrong with
- * the channel.
- */
- delay(drv_usectohz(10000)); /* 1/1000 sec */
- } else {
- /* fail */
- return (rv);
- }
+ DS_DBG_LDC("ds@%lx: attempting to read %ld bytes\n", port->id,
+ bytes_req);
+
+ while (bytes_left > 0) {
+
+ nbytes = bytes_left;
+
+ if ((rv = ldc_read(port->ldc.hdl, msgp, &nbytes)) != 0) {
+ if (rv != EAGAIN)
+ break;
} else {
+ if (nbytes != 0) {
+ DS_DBG_LDC("ds@%lx: read %ld bytes, %d "
+ "retries\n", port->id, nbytes, retry_count);
+
+ *sizep += nbytes;
+ msgp += nbytes;
+ bytes_left -= nbytes;
+
+ /* reset counter on a successful read */
+ retry_count = 0;
+ continue;
+ }
+
/*
- * Check for a zero length read. This
- * indicates that there is no more data
- * to read from the channel.
+ * No data was read. Check if this is the
+ * first attempt. If so, just return since
+ * nothing has been read yet.
*/
- if (amt_left == 0)
+ if (bytes_left == bytes_req) {
+ DS_DBG_LDC("ds@%lx: read zero bytes, no data "
+ "available\n", port->id);
break;
+ }
+ }
- *sizep += amt_left;
- msgp += amt_left;
- msglen -= amt_left;
- amt_left = msglen;
+ /*
+ * A retry is necessary because the read returned
+ * EAGAIN, or a zero length read occurred after
+ * reading a partial message.
+ */
+ if (retry_count++ >= ds_retries) {
+ DS_DBG_LDC("ds@%lx: timed out waiting for "
+ "message\n", port->id);
+ break;
}
+
+ drv_usecwait(ds_delay);
}
return (rv);
@@ -845,7 +878,7 @@ ds_handle_recv(void *arg)
currp = hbuf;
/* read in the message header */
- if ((rv = ds_recv_msg(ldc_hdl, currp, &read_size)) != 0) {
+ if ((rv = ds_recv_msg(port, currp, &read_size)) != 0) {
cmn_err(CE_NOTE, "ds@%lx: ldc_read returned %d",
port->id, rv);
continue;
@@ -874,7 +907,7 @@ ds_handle_recv(void *arg)
currp = (char *)(msg) + DS_HDR_SZ;
/* read in the message body */
- if ((rv = ds_recv_msg(ldc_hdl, currp, &read_size)) != 0) {
+ if ((rv = ds_recv_msg(port, currp, &read_size)) != 0) {
cmn_err(CE_NOTE, "ds@%lx: ldc_read returned %d",
port->id, rv);
kmem_free(msg, msglen);
@@ -890,7 +923,7 @@ ds_handle_recv(void *arg)
continue;
}
- DS_DUMP_LDC_MSG(msg, msglen);
+ DS_DUMP_MSG(msg, msglen);
/*
* Send the message for processing, and store it
@@ -1555,7 +1588,8 @@ ds_send_msg(ds_port_t *port, caddr_t msg, size_t msglen)
size_t amt_left = msglen;
int loopcnt = 0;
- DS_DUMP_LDC_MSG(msg, msglen);
+ DS_DUMP_MSG(msg, msglen);
+
(void) ds_log_add_msg(DS_LOG_OUT(port->id), (uint8_t *)msg, msglen);
/*
@@ -1568,12 +1602,8 @@ ds_send_msg(ds_port_t *port, caddr_t msg, size_t msglen)
/* send the message */
do {
if ((rv = ldc_write(port->ldc.hdl, currp, &msglen)) != 0) {
- if ((rv == EWOULDBLOCK) && (loopcnt++ < 1000)) {
- /*
- * don't try for more than a sec. Something
- * is wrong with the channel.
- */
- delay(drv_usectohz(10000)); /* 1/1000 sec */
+ if ((rv == EWOULDBLOCK) && (loopcnt++ < ds_retries)) {
+ drv_usecwait(ds_delay);
} else {
cmn_err(CE_WARN,
"ds@%lx: send_msg: ldc_write failed (%d)",
@@ -1879,7 +1909,7 @@ ds_send_data_nack(ds_port_t *port, ds_svc_hdl_t bad_hdl)
* and '.' otherwise.
*/
static void
-ds_dump_ldc_msg(void *vbuf, size_t len)
+ds_dump_msg(void *vbuf, size_t len)
{
int i, j;
char *curr;
@@ -1888,7 +1918,7 @@ ds_dump_ldc_msg(void *vbuf, size_t len)
uint8_t *buf = vbuf;
/* abort if not debugging ldc */
- if (!(ds_debug & DS_DBG_FLAG_LDC)) {
+ if (!(ds_debug & DS_DBG_FLAG_MSG)) {
return;
}
@@ -1923,7 +1953,7 @@ ds_dump_ldc_msg(void *vbuf, size_t len)
while (curr != (line + ASCIIOFFSET))
*curr++ = ' ';
- DS_DBG_LDC("%s\n", line);
+ DS_DBG_MSG("%s\n", line);
}
}
#endif /* DEBUG */
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-11 22:51:42 +0000