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synclink: kill the big kernel lock
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We don't need it while waiting and we can lock the ioctls using the port
mutex. While at it eliminate use of the hangup mutex and switch to the port
mutex.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Alan Cox authored and Greg Kroah-Hartman committed Aug 10, 2010
1 parent 417b6e0 commit f602501
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Showing 3 changed files with 56 additions and 73 deletions.
19 changes: 10 additions & 9 deletions drivers/char/synclink.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -81,7 +81,6 @@
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
Expand Down Expand Up @@ -2436,7 +2435,9 @@ static int mgsl_get_stats(struct mgsl_struct * info, struct mgsl_icount __user *
if (!user_icount) {
memset(&info->icount, 0, sizeof(info->icount));
} else {
mutex_lock(&info->port.mutex);
COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
mutex_unlock(&info->port.mutex);
if (err)
return -EFAULT;
}
Expand All @@ -2461,7 +2462,9 @@ static int mgsl_get_params(struct mgsl_struct * info, MGSL_PARAMS __user *user_p
printk("%s(%d):mgsl_get_params(%s)\n",
__FILE__,__LINE__, info->device_name);

mutex_lock(&info->port.mutex);
COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
mutex_unlock(&info->port.mutex);
if (err) {
if ( debug_level >= DEBUG_LEVEL_INFO )
printk( "%s(%d):mgsl_get_params(%s) user buffer copy failed\n",
Expand Down Expand Up @@ -2501,11 +2504,13 @@ static int mgsl_set_params(struct mgsl_struct * info, MGSL_PARAMS __user *new_pa
return -EFAULT;
}

mutex_lock(&info->port.mutex);
spin_lock_irqsave(&info->irq_spinlock,flags);
memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
spin_unlock_irqrestore(&info->irq_spinlock,flags);

mgsl_change_params(info);
mutex_unlock(&info->port.mutex);

return 0;

Expand Down Expand Up @@ -2935,7 +2940,6 @@ static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct mgsl_struct * info = tty->driver_data;
int ret;

if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):mgsl_ioctl %s cmd=%08X\n", __FILE__,__LINE__,
Expand All @@ -2950,10 +2954,7 @@ static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
return -EIO;
}

lock_kernel();
ret = mgsl_ioctl_common(info, cmd, arg);
unlock_kernel();
return ret;
return mgsl_ioctl_common(info, cmd, arg);
}

static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg)
Expand Down Expand Up @@ -3109,12 +3110,14 @@ static void mgsl_close(struct tty_struct *tty, struct file * filp)

if (tty_port_close_start(&info->port, tty, filp) == 0)
goto cleanup;


mutex_lock(&info->port.mutex);
if (info->port.flags & ASYNC_INITIALIZED)
mgsl_wait_until_sent(tty, info->timeout);
mgsl_flush_buffer(tty);
tty_ldisc_flush(tty);
shutdown(info);
mutex_unlock(&info->port.mutex);

tty_port_close_end(&info->port, tty);
info->port.tty = NULL;
Expand Down Expand Up @@ -3162,7 +3165,6 @@ static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout)
* Note: use tight timings here to satisfy the NIST-PCTS.
*/

lock_kernel();
if ( info->params.data_rate ) {
char_time = info->timeout/(32 * 5);
if (!char_time)
Expand Down Expand Up @@ -3192,7 +3194,6 @@ static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout)
break;
}
}
unlock_kernel();

exit:
if (debug_level >= DEBUG_LEVEL_INFO)
Expand Down
78 changes: 34 additions & 44 deletions drivers/char/synclink_gt.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -40,8 +40,8 @@
#define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
#define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
#define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
//#define DBGTBUF(info) dump_tbufs(info)
//#define DBGRBUF(info) dump_rbufs(info)
/*#define DBGTBUF(info) dump_tbufs(info)*/
/*#define DBGRBUF(info) dump_rbufs(info)*/


#include <linux/module.h>
Expand All @@ -62,7 +62,6 @@
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
Expand Down Expand Up @@ -901,8 +900,6 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
* Note: use tight timings here to satisfy the NIST-PCTS.
*/

lock_kernel();

if (info->params.data_rate) {
char_time = info->timeout/(32 * 5);
if (!char_time)
Expand All @@ -920,8 +917,6 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
if (timeout && time_after(jiffies, orig_jiffies + timeout))
break;
}
unlock_kernel();

exit:
DBGINFO(("%s wait_until_sent exit\n", info->device_name));
}
Expand Down Expand Up @@ -1041,8 +1036,37 @@ static int ioctl(struct tty_struct *tty, struct file *file,
return -EIO;
}

lock_kernel();

switch (cmd) {
case MGSL_IOCWAITEVENT:
return wait_mgsl_event(info, argp);
case TIOCMIWAIT:
return modem_input_wait(info,(int)arg);
case TIOCGICOUNT:
spin_lock_irqsave(&info->lock,flags);
cnow = info->icount;
spin_unlock_irqrestore(&info->lock,flags);
p_cuser = argp;
if (put_user(cnow.cts, &p_cuser->cts) ||
put_user(cnow.dsr, &p_cuser->dsr) ||
put_user(cnow.rng, &p_cuser->rng) ||
put_user(cnow.dcd, &p_cuser->dcd) ||
put_user(cnow.rx, &p_cuser->rx) ||
put_user(cnow.tx, &p_cuser->tx) ||
put_user(cnow.frame, &p_cuser->frame) ||
put_user(cnow.overrun, &p_cuser->overrun) ||
put_user(cnow.parity, &p_cuser->parity) ||
put_user(cnow.brk, &p_cuser->brk) ||
put_user(cnow.buf_overrun, &p_cuser->buf_overrun))
return -EFAULT;
return 0;
case MGSL_IOCSGPIO:
return set_gpio(info, argp);
case MGSL_IOCGGPIO:
return get_gpio(info, argp);
case MGSL_IOCWAITGPIO:
return wait_gpio(info, argp);
}
mutex_lock(&info->port.mutex);
switch (cmd) {
case MGSL_IOCGPARAMS:
ret = get_params(info, argp);
Expand All @@ -1068,50 +1092,16 @@ static int ioctl(struct tty_struct *tty, struct file *file,
case MGSL_IOCGSTATS:
ret = get_stats(info, argp);
break;
case MGSL_IOCWAITEVENT:
ret = wait_mgsl_event(info, argp);
break;
case TIOCMIWAIT:
ret = modem_input_wait(info,(int)arg);
break;
case MGSL_IOCGIF:
ret = get_interface(info, argp);
break;
case MGSL_IOCSIF:
ret = set_interface(info,(int)arg);
break;
case MGSL_IOCSGPIO:
ret = set_gpio(info, argp);
break;
case MGSL_IOCGGPIO:
ret = get_gpio(info, argp);
break;
case MGSL_IOCWAITGPIO:
ret = wait_gpio(info, argp);
break;
case TIOCGICOUNT:
spin_lock_irqsave(&info->lock,flags);
cnow = info->icount;
spin_unlock_irqrestore(&info->lock,flags);
p_cuser = argp;
if (put_user(cnow.cts, &p_cuser->cts) ||
put_user(cnow.dsr, &p_cuser->dsr) ||
put_user(cnow.rng, &p_cuser->rng) ||
put_user(cnow.dcd, &p_cuser->dcd) ||
put_user(cnow.rx, &p_cuser->rx) ||
put_user(cnow.tx, &p_cuser->tx) ||
put_user(cnow.frame, &p_cuser->frame) ||
put_user(cnow.overrun, &p_cuser->overrun) ||
put_user(cnow.parity, &p_cuser->parity) ||
put_user(cnow.brk, &p_cuser->brk) ||
put_user(cnow.buf_overrun, &p_cuser->buf_overrun))
ret = -EFAULT;
ret = 0;
break;
default:
ret = -ENOIOCTLCMD;
}
unlock_kernel();
mutex_unlock(&info->port.mutex);
return ret;
}

Expand Down
32 changes: 12 additions & 20 deletions drivers/char/synclinkmp.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -52,7 +52,6 @@
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
Expand Down Expand Up @@ -1062,9 +1061,7 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
if (sanity_check(info, tty->name, "wait_until_sent"))
return;

lock_kernel();

if (!(info->port.flags & ASYNC_INITIALIZED))
if (!test_bit(ASYNCB_INITIALIZED, &info->port.flags))
goto exit;

orig_jiffies = jiffies;
Expand Down Expand Up @@ -1094,8 +1091,10 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
break;
}
} else {
//TODO: determine if there is something similar to USC16C32
// TXSTATUS_ALL_SENT status
/*
* TODO: determine if there is something similar to USC16C32
* TXSTATUS_ALL_SENT status
*/
while ( info->tx_active && info->tx_enabled) {
msleep_interruptible(jiffies_to_msecs(char_time));
if (signal_pending(current))
Expand All @@ -1106,7 +1105,6 @@ static void wait_until_sent(struct tty_struct *tty, int timeout)
}

exit:
unlock_kernel();
if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):%s wait_until_sent() exit\n",
__FILE__,__LINE__, info->device_name );
Expand All @@ -1122,15 +1120,13 @@ static int write_room(struct tty_struct *tty)
if (sanity_check(info, tty->name, "write_room"))
return 0;

lock_kernel();
if (info->params.mode == MGSL_MODE_HDLC) {
ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
} else {
ret = info->max_frame_size - info->tx_count - 1;
if (ret < 0)
ret = 0;
}
unlock_kernel();

if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):%s write_room()=%d\n",
Expand Down Expand Up @@ -1251,7 +1247,7 @@ static void tx_release(struct tty_struct *tty)
*
* Return Value: 0 if success, otherwise error code
*/
static int do_ioctl(struct tty_struct *tty, struct file *file,
static int ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
SLMP_INFO *info = tty->driver_data;
Expand Down Expand Up @@ -1341,16 +1337,6 @@ static int do_ioctl(struct tty_struct *tty, struct file *file,
return 0;
}

static int ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
int ret;
lock_kernel();
ret = do_ioctl(tty, file, cmd, arg);
unlock_kernel();
return ret;
}

/*
* /proc fs routines....
*/
Expand Down Expand Up @@ -2883,7 +2869,9 @@ static int get_stats(SLMP_INFO * info, struct mgsl_icount __user *user_icount)
if (!user_icount) {
memset(&info->icount, 0, sizeof(info->icount));
} else {
mutex_lock(&info->port.mutex);
COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
mutex_unlock(&info->port.mutex);
if (err)
return -EFAULT;
}
Expand All @@ -2898,7 +2886,9 @@ static int get_params(SLMP_INFO * info, MGSL_PARAMS __user *user_params)
printk("%s(%d):%s get_params()\n",
__FILE__,__LINE__, info->device_name);

mutex_lock(&info->port.mutex);
COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
mutex_unlock(&info->port.mutex);
if (err) {
if ( debug_level >= DEBUG_LEVEL_INFO )
printk( "%s(%d):%s get_params() user buffer copy failed\n",
Expand Down Expand Up @@ -2926,11 +2916,13 @@ static int set_params(SLMP_INFO * info, MGSL_PARAMS __user *new_params)
return -EFAULT;
}

mutex_lock(&info->port.mutex);
spin_lock_irqsave(&info->lock,flags);
memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
spin_unlock_irqrestore(&info->lock,flags);

change_params(info);
mutex_unlock(&info->port.mutex);

return 0;
}
Expand Down

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