isdn/gigaset: avoid copying AT commands twice

Change the Gigaset driver's internal write_cmd interface to accept a
cmdbuf structure instead of a string. This avoids copying formatted
AT commands a second time.

Impact: optimization
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tilman Schmidt 2010-07-05 14:18:43 +00:00 committed by David S. Miller
parent b3251d8045
commit e3628dd176
6 changed files with 85 additions and 134 deletions

View File

@ -1913,65 +1913,41 @@ static int start_cbsend(struct cardstate *cs)
* USB transmission is started if necessary.
* parameters:
* cs controller state structure
* buf command string to send
* len number of bytes to send (max. IF_WRITEBUF)
* wake_tasklet tasklet to run when transmission is completed
* (NULL if none)
* cb command buffer structure
* return value:
* number of bytes queued on success
* error code < 0 on error
*/
static int gigaset_write_cmd(struct cardstate *cs,
const unsigned char *buf, int len,
struct tasklet_struct *wake_tasklet)
static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb)
{
struct cmdbuf_t *cb;
unsigned long flags;
int rc;
gigaset_dbg_buffer(cs->mstate != MS_LOCKED ?
DEBUG_TRANSCMD : DEBUG_LOCKCMD,
"CMD Transmit", len, buf);
if (len <= 0) {
/* nothing to do */
rc = 0;
goto notqueued;
}
"CMD Transmit", cb->len, cb->buf);
/* translate "+++" escape sequence sent as a single separate command
* into "close AT channel" command for error recovery
* The next command will reopen the AT channel automatically.
*/
if (len == 3 && !memcmp(buf, "+++", 3)) {
if (cb->len == 3 && !memcmp(cb->buf, "+++", 3)) {
kfree(cb);
rc = req_submit(cs->bcs, HD_CLOSE_ATCHANNEL, 0, BAS_TIMEOUT);
goto notqueued;
if (cb->wake_tasklet)
tasklet_schedule(cb->wake_tasklet);
return rc < 0 ? rc : cb->len;
}
if (len > IF_WRITEBUF)
len = IF_WRITEBUF;
cb = kmalloc(sizeof(struct cmdbuf_t) + len, GFP_ATOMIC);
if (!cb) {
dev_err(cs->dev, "%s: out of memory\n", __func__);
rc = -ENOMEM;
goto notqueued;
}
memcpy(cb->buf, buf, len);
cb->len = len;
cb->offset = 0;
cb->next = NULL;
cb->wake_tasklet = wake_tasklet;
spin_lock_irqsave(&cs->cmdlock, flags);
cb->prev = cs->lastcmdbuf;
if (cs->lastcmdbuf)
cs->lastcmdbuf->next = cb;
else {
cs->cmdbuf = cb;
cs->curlen = len;
cs->curlen = cb->len;
}
cs->cmdbytes += len;
cs->cmdbytes += cb->len;
cs->lastcmdbuf = cb;
spin_unlock_irqrestore(&cs->cmdlock, flags);
@ -1988,12 +1964,7 @@ static int gigaset_write_cmd(struct cardstate *cs,
}
rc = start_cbsend(cs);
spin_unlock_irqrestore(&cs->lock, flags);
return rc < 0 ? rc : len;
notqueued: /* request handled without queuing */
if (wake_tasklet)
tasklet_schedule(wake_tasklet);
return rc;
return rc < 0 ? rc : cb->len;
}
/* gigaset_write_room

View File

@ -797,48 +797,27 @@ static void schedule_init(struct cardstate *cs, int state)
static void send_command(struct cardstate *cs, const char *cmd, int cid,
int dle, gfp_t kmallocflags)
{
size_t cmdlen, buflen;
char *cmdpos, *cmdbuf, *cmdtail;
struct cmdbuf_t *cb;
size_t buflen;
cmdlen = strlen(cmd);
buflen = 11 + cmdlen;
if (unlikely(buflen <= cmdlen)) {
dev_err(cs->dev, "integer overflow in buflen\n");
buflen = strlen(cmd) + 12; /* DLE ( A T 1 2 3 4 5 <cmd> DLE ) \0 */
cb = kmalloc(sizeof(struct cmdbuf_t) + buflen, kmallocflags);
if (!cb) {
dev_err(cs->dev, "%s: out of memory\n", __func__);
return;
}
cmdbuf = kmalloc(buflen, kmallocflags);
if (unlikely(!cmdbuf)) {
dev_err(cs->dev, "out of memory\n");
return;
}
cmdpos = cmdbuf + 9;
cmdtail = cmdpos + cmdlen;
memcpy(cmdpos, cmd, cmdlen);
if (cid > 0 && cid <= 65535) {
do {
*--cmdpos = '0' + cid % 10;
cid /= 10;
++cmdlen;
} while (cid);
}
cmdlen += 2;
*--cmdpos = 'T';
*--cmdpos = 'A';
if (dle) {
cmdlen += 4;
*--cmdpos = '(';
*--cmdpos = 0x10;
*cmdtail++ = 0x10;
*cmdtail++ = ')';
}
cs->ops->write_cmd(cs, cmdpos, cmdlen, NULL);
kfree(cmdbuf);
if (cid > 0 && cid <= 65535)
cb->len = snprintf(cb->buf, buflen,
dle ? "\020(AT%d%s\020)" : "AT%d%s",
cid, cmd);
else
cb->len = snprintf(cb->buf, buflen,
dle ? "\020(AT%s\020)" : "AT%s",
cmd);
cb->offset = 0;
cb->next = NULL;
cb->wake_tasklet = NULL;
cs->ops->write_cmd(cs, cb);
}
static struct at_state_t *at_state_from_cid(struct cardstate *cs, int cid)
@ -1240,8 +1219,22 @@ static void do_action(int action, struct cardstate *cs,
break;
case ACT_HUPMODEM:
/* send "+++" (hangup in unimodem mode) */
if (cs->connected)
cs->ops->write_cmd(cs, "+++", 3, NULL);
if (cs->connected) {
struct cmdbuf_t *cb;
cb = kmalloc(sizeof(struct cmdbuf_t) + 3, GFP_ATOMIC);
if (!cb) {
dev_err(cs->dev, "%s: out of memory\n",
__func__);
return;
}
memcpy(cb->buf, "+++", 3);
cb->len = 3;
cb->offset = 0;
cb->next = NULL;
cb->wake_tasklet = NULL;
cs->ops->write_cmd(cs, cb);
}
break;
case ACT_RING:
/* get fresh AT state structure for new CID */

View File

@ -574,9 +574,7 @@ struct bas_bc_state {
struct gigaset_ops {
/* Called from ev-layer.c/interface.c for sending AT commands to the
device */
int (*write_cmd)(struct cardstate *cs,
const unsigned char *buf, int len,
struct tasklet_struct *wake_tasklet);
int (*write_cmd)(struct cardstate *cs, struct cmdbuf_t *cb);
/* Called from interface.c for additional device control */
int (*write_room)(struct cardstate *cs);

View File

@ -339,7 +339,8 @@ static int if_tiocmset(struct tty_struct *tty, struct file *file,
static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
struct cardstate *cs;
int retval = -ENODEV;
struct cmdbuf_t *cb;
int retval;
cs = (struct cardstate *) tty->driver_data;
if (!cs) {
@ -355,18 +356,39 @@ static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
if (!cs->connected) {
gig_dbg(DEBUG_IF, "not connected");
retval = -ENODEV;
} else if (!cs->open_count)
goto done;
}
if (!cs->open_count) {
dev_warn(cs->dev, "%s: device not opened\n", __func__);
else if (cs->mstate != MS_LOCKED) {
retval = -ENODEV;
goto done;
}
if (cs->mstate != MS_LOCKED) {
dev_warn(cs->dev, "can't write to unlocked device\n");
retval = -EBUSY;
} else {
retval = cs->ops->write_cmd(cs, buf, count,
&cs->if_wake_tasklet);
goto done;
}
if (count <= 0) {
/* nothing to do */
retval = 0;
goto done;
}
mutex_unlock(&cs->mutex);
cb = kmalloc(sizeof(struct cmdbuf_t) + count, GFP_KERNEL);
if (!cb) {
dev_err(cs->dev, "%s: out of memory\n", __func__);
retval = -ENOMEM;
goto done;
}
memcpy(cb->buf, buf, count);
cb->len = count;
cb->offset = 0;
cb->next = NULL;
cb->wake_tasklet = &cs->if_wake_tasklet;
retval = cs->ops->write_cmd(cs, cb);
done:
mutex_unlock(&cs->mutex);
return retval;
}

View File

@ -241,30 +241,13 @@ static void flush_send_queue(struct cardstate *cs)
* return value:
* number of bytes queued, or error code < 0
*/
static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
int len, struct tasklet_struct *wake_tasklet)
static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb)
{
struct cmdbuf_t *cb;
unsigned long flags;
gigaset_dbg_buffer(cs->mstate != MS_LOCKED ?
DEBUG_TRANSCMD : DEBUG_LOCKCMD,
"CMD Transmit", len, buf);
if (len <= 0)
return 0;
cb = kmalloc(sizeof(struct cmdbuf_t) + len, GFP_ATOMIC);
if (!cb) {
dev_err(cs->dev, "%s: out of memory!\n", __func__);
return -ENOMEM;
}
memcpy(cb->buf, buf, len);
cb->len = len;
cb->offset = 0;
cb->next = NULL;
cb->wake_tasklet = wake_tasklet;
"CMD Transmit", cb->len, cb->buf);
spin_lock_irqsave(&cs->cmdlock, flags);
cb->prev = cs->lastcmdbuf;
@ -272,9 +255,9 @@ static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
cs->lastcmdbuf->next = cb;
else {
cs->cmdbuf = cb;
cs->curlen = len;
cs->curlen = cb->len;
}
cs->cmdbytes += len;
cs->cmdbytes += cb->len;
cs->lastcmdbuf = cb;
spin_unlock_irqrestore(&cs->cmdlock, flags);
@ -282,7 +265,7 @@ static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
if (cs->connected)
tasklet_schedule(&cs->write_tasklet);
spin_unlock_irqrestore(&cs->lock, flags);
return len;
return cb->len;
}
/*

View File

@ -494,29 +494,13 @@ static int send_cb(struct cardstate *cs, struct cmdbuf_t *cb)
}
/* Send command to device. */
static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
int len, struct tasklet_struct *wake_tasklet)
static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb)
{
struct cmdbuf_t *cb;
unsigned long flags;
gigaset_dbg_buffer(cs->mstate != MS_LOCKED ?
DEBUG_TRANSCMD : DEBUG_LOCKCMD,
"CMD Transmit", len, buf);
if (len <= 0)
return 0;
cb = kmalloc(sizeof(struct cmdbuf_t) + len, GFP_ATOMIC);
if (!cb) {
dev_err(cs->dev, "%s: out of memory\n", __func__);
return -ENOMEM;
}
memcpy(cb->buf, buf, len);
cb->len = len;
cb->offset = 0;
cb->next = NULL;
cb->wake_tasklet = wake_tasklet;
"CMD Transmit", cb->len, cb->buf);
spin_lock_irqsave(&cs->cmdlock, flags);
cb->prev = cs->lastcmdbuf;
@ -524,9 +508,9 @@ static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
cs->lastcmdbuf->next = cb;
else {
cs->cmdbuf = cb;
cs->curlen = len;
cs->curlen = cb->len;
}
cs->cmdbytes += len;
cs->cmdbytes += cb->len;
cs->lastcmdbuf = cb;
spin_unlock_irqrestore(&cs->cmdlock, flags);
@ -534,7 +518,7 @@ static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
if (cs->connected)
tasklet_schedule(&cs->write_tasklet);
spin_unlock_irqrestore(&cs->lock, flags);
return len;
return cb->len;
}
static int gigaset_write_room(struct cardstate *cs)