* [PATCH 1/4] Staging: comedi: Use mutex instead of semaphore
2015-10-01 16:05 [PATCH 0/4] Use mutex instead of semaphore Ksenija Stanojevic
@ 2015-10-01 16:06 ` Ksenija Stanojevic
2015-10-01 16:07 ` [PATCH 2/4] " Ksenija Stanojevic
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Ksenija Stanojevic @ 2015-10-01 16:06 UTC (permalink / raw)
To: outreachy-kernel; +Cc: Ksenija Stanojevic
Replace binary semaphore with mutex because mutex gives better
performance.
Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
---
drivers/staging/comedi/drivers/usbduxsigma.c | 70 ++++++++++++++--------------
1 file changed, 35 insertions(+), 35 deletions(-)
diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c b/drivers/staging/comedi/drivers/usbduxsigma.c
index d49147b..456e9f1 100644
--- a/drivers/staging/comedi/drivers/usbduxsigma.c
+++ b/drivers/staging/comedi/drivers/usbduxsigma.c
@@ -173,7 +173,7 @@ struct usbduxsigma_private {
unsigned int ai_interval;
/* commands */
u8 *dux_commands;
- struct semaphore sem;
+ struct mutex mut;
};
static void usbduxsigma_unlink_urbs(struct urb **urbs, int num_urbs)
@@ -199,10 +199,10 @@ static int usbduxsigma_ai_cancel(struct comedi_device *dev,
{
struct usbduxsigma_private *devpriv = dev->private;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* unlink only if it is really running */
usbduxsigma_ai_stop(dev, devpriv->ai_cmd_running);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 0;
}
@@ -325,10 +325,10 @@ static int usbduxsigma_ao_cancel(struct comedi_device *dev,
{
struct usbduxsigma_private *devpriv = dev->private;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* unlink only if it is really running */
usbduxsigma_ao_stop(dev, devpriv->ao_cmd_running);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 0;
}
@@ -609,19 +609,19 @@ static int usbduxsigma_ai_inttrig(struct comedi_device *dev,
if (trig_num != cmd->start_arg)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (!devpriv->ai_cmd_running) {
devpriv->ai_cmd_running = 1;
ret = usbduxsigma_submit_urbs(dev, devpriv->ai_urbs,
devpriv->n_ai_urbs, 1);
if (ret < 0) {
devpriv->ai_cmd_running = 0;
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
s->async->inttrig = NULL;
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 1;
}
@@ -638,7 +638,7 @@ static int usbduxsigma_ai_cmd(struct comedi_device *dev,
int ret;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->high_speed) {
/*
@@ -673,7 +673,7 @@ static int usbduxsigma_ai_cmd(struct comedi_device *dev,
ret = usbbuxsigma_send_cmd(dev, USBBUXSIGMA_AD_CMD);
if (ret < 0) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -686,7 +686,7 @@ static int usbduxsigma_ai_cmd(struct comedi_device *dev,
devpriv->n_ai_urbs, 1);
if (ret < 0) {
devpriv->ai_cmd_running = 0;
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
s->async->inttrig = NULL;
@@ -694,7 +694,7 @@ static int usbduxsigma_ai_cmd(struct comedi_device *dev,
s->async->inttrig = usbduxsigma_ai_inttrig;
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 0;
}
@@ -712,9 +712,9 @@ static int usbduxsigma_ai_insn_read(struct comedi_device *dev,
int ret;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ai_cmd_running) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return -EBUSY;
}
@@ -731,7 +731,7 @@ static int usbduxsigma_ai_insn_read(struct comedi_device *dev,
/* adc commands */
ret = usbbuxsigma_send_cmd(dev, USBDUXSIGMA_SINGLE_AD_CMD);
if (ret < 0) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -740,7 +740,7 @@ static int usbduxsigma_ai_insn_read(struct comedi_device *dev,
ret = usbduxsigma_receive_cmd(dev, USBDUXSIGMA_SINGLE_AD_CMD);
if (ret < 0) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -750,7 +750,7 @@ static int usbduxsigma_ai_insn_read(struct comedi_device *dev,
val &= 0x00ffffff; /* strip status byte */
data[i] = comedi_offset_munge(s, val);
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return insn->n;
}
@@ -763,9 +763,9 @@ static int usbduxsigma_ao_insn_read(struct comedi_device *dev,
struct usbduxsigma_private *devpriv = dev->private;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
ret = comedi_readback_insn_read(dev, s, insn, data);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -780,9 +780,9 @@ static int usbduxsigma_ao_insn_write(struct comedi_device *dev,
int ret;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ao_cmd_running) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return -EBUSY;
}
@@ -792,12 +792,12 @@ static int usbduxsigma_ao_insn_write(struct comedi_device *dev,
devpriv->dux_commands[3] = chan; /* channel number */
ret = usbbuxsigma_send_cmd(dev, USBDUXSIGMA_DA_CMD);
if (ret < 0) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
s->readback[chan] = data[i];
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return insn->n;
}
@@ -813,19 +813,19 @@ static int usbduxsigma_ao_inttrig(struct comedi_device *dev,
if (trig_num != cmd->start_arg)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (!devpriv->ao_cmd_running) {
devpriv->ao_cmd_running = 1;
ret = usbduxsigma_submit_urbs(dev, devpriv->ao_urbs,
devpriv->n_ao_urbs, 0);
if (ret < 0) {
devpriv->ao_cmd_running = 0;
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
s->async->inttrig = NULL;
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 1;
}
@@ -856,7 +856,7 @@ static int usbduxsigma_ao_cmdtest(struct comedi_device *dev,
err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
if (err) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 1;
}
@@ -905,7 +905,7 @@ static int usbduxsigma_ao_cmd(struct comedi_device *dev,
struct comedi_cmd *cmd = &s->async->cmd;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/*
* For now, only "scan" timing is supported. A future version may
@@ -924,7 +924,7 @@ static int usbduxsigma_ao_cmd(struct comedi_device *dev,
devpriv->n_ao_urbs, 0);
if (ret < 0) {
devpriv->ao_cmd_running = 0;
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
s->async->inttrig = NULL;
@@ -932,7 +932,7 @@ static int usbduxsigma_ao_cmd(struct comedi_device *dev,
s->async->inttrig = usbduxsigma_ao_inttrig;
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 0;
}
@@ -963,7 +963,7 @@ static int usbduxsigma_dio_insn_bits(struct comedi_device *dev,
struct usbduxsigma_private *devpriv = dev->private;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
comedi_dio_update_state(s, data);
@@ -990,7 +990,7 @@ static int usbduxsigma_dio_insn_bits(struct comedi_device *dev,
ret = insn->n;
done:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -1462,7 +1462,7 @@ static int usbduxsigma_auto_attach(struct comedi_device *dev,
if (!devpriv)
return -ENOMEM;
- sema_init(&devpriv->sem, 1);
+ mutex_init(&devpriv->mut);
usb_set_intfdata(intf, devpriv);
@@ -1576,7 +1576,7 @@ static void usbduxsigma_detach(struct comedi_device *dev)
if (!devpriv)
return;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* force unlink all urbs */
usbduxsigma_ai_stop(dev, 1);
@@ -1585,7 +1585,7 @@ static void usbduxsigma_detach(struct comedi_device *dev)
usbduxsigma_free_usb_buffers(dev);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
}
static struct comedi_driver usbduxsigma_driver = {
--
1.9.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 2/4] Staging: comedi: Use mutex instead of semaphore
2015-10-01 16:05 [PATCH 0/4] Use mutex instead of semaphore Ksenija Stanojevic
2015-10-01 16:06 ` [PATCH 1/4] Staging: comedi: " Ksenija Stanojevic
@ 2015-10-01 16:07 ` Ksenija Stanojevic
2015-10-01 16:07 ` [PATCH 3/4] " Ksenija Stanojevic
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Ksenija Stanojevic @ 2015-10-01 16:07 UTC (permalink / raw)
To: outreachy-kernel; +Cc: Ksenija Stanojevic
Replace binary semaphore with mutex because mutex gives better
performance.
Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
---
drivers/staging/comedi/drivers/usbdux.c | 64 ++++++++++++++++-----------------
1 file changed, 32 insertions(+), 32 deletions(-)
diff --git a/drivers/staging/comedi/drivers/usbdux.c b/drivers/staging/comedi/drivers/usbdux.c
index 39710f2..f4f05d2 100644
--- a/drivers/staging/comedi/drivers/usbdux.c
+++ b/drivers/staging/comedi/drivers/usbdux.c
@@ -210,7 +210,7 @@ struct usbdux_private {
unsigned int ai_interval;
/* commands */
u8 *dux_commands;
- struct semaphore sem;
+ struct mutex mut;
};
static void usbdux_unlink_urbs(struct urb **urbs, int num_urbs)
@@ -237,10 +237,10 @@ static int usbdux_ai_cancel(struct comedi_device *dev,
struct usbdux_private *devpriv = dev->private;
/* prevent other CPUs from submitting new commands just now */
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* unlink only if the urb really has been submitted */
usbdux_ai_stop(dev, devpriv->ai_cmd_running);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 0;
}
@@ -365,10 +365,10 @@ static int usbdux_ao_cancel(struct comedi_device *dev,
struct usbdux_private *devpriv = dev->private;
/* prevent other CPUs from submitting a command just now */
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* unlink only if it is really running */
usbdux_ao_stop(dev, devpriv->ao_cmd_running);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 0;
}
@@ -646,7 +646,7 @@ static int usbdux_ai_inttrig(struct comedi_device *dev,
if (trig_num != cmd->start_arg)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (!devpriv->ai_cmd_running) {
devpriv->ai_cmd_running = 1;
@@ -662,7 +662,7 @@ static int usbdux_ai_inttrig(struct comedi_device *dev,
}
ai_trig_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -675,7 +675,7 @@ static int usbdux_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
int i;
/* block other CPUs from starting an ai_cmd */
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ai_cmd_running)
goto ai_cmd_exit;
@@ -736,7 +736,7 @@ static int usbdux_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
}
ai_cmd_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -754,7 +754,7 @@ static int usbdux_ai_insn_read(struct comedi_device *dev,
int ret = -EBUSY;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ai_cmd_running)
goto ai_read_exit;
@@ -782,7 +782,7 @@ static int usbdux_ai_insn_read(struct comedi_device *dev,
}
ai_read_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret ? ret : insn->n;
}
@@ -795,9 +795,9 @@ static int usbdux_ao_insn_read(struct comedi_device *dev,
struct usbdux_private *devpriv = dev->private;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
ret = comedi_readback_insn_read(dev, s, insn, data);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -814,7 +814,7 @@ static int usbdux_ao_insn_write(struct comedi_device *dev,
int ret = -EBUSY;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ao_cmd_running)
goto ao_write_exit;
@@ -838,7 +838,7 @@ static int usbdux_ao_insn_write(struct comedi_device *dev,
}
ao_write_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret ? ret : insn->n;
}
@@ -854,7 +854,7 @@ static int usbdux_ao_inttrig(struct comedi_device *dev,
if (trig_num != cmd->start_arg)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (!devpriv->ao_cmd_running) {
devpriv->ao_cmd_running = 1;
@@ -870,7 +870,7 @@ static int usbdux_ao_inttrig(struct comedi_device *dev,
}
ao_trig_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -960,7 +960,7 @@ static int usbdux_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
struct comedi_cmd *cmd = &s->async->cmd;
int ret = -EBUSY;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ao_cmd_running)
goto ao_cmd_exit;
@@ -1002,7 +1002,7 @@ static int usbdux_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
}
ao_cmd_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -1033,7 +1033,7 @@ static int usbdux_dio_insn_bits(struct comedi_device *dev,
struct usbdux_private *devpriv = dev->private;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
comedi_dio_update_state(s, data);
@@ -1055,7 +1055,7 @@ static int usbdux_dio_insn_bits(struct comedi_device *dev,
data[1] = le16_to_cpu(devpriv->insn_buf[1]);
dio_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret ? ret : insn->n;
}
@@ -1070,7 +1070,7 @@ static int usbdux_counter_read(struct comedi_device *dev,
int ret = 0;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
for (i = 0; i < insn->n; i++) {
ret = send_dux_commands(dev, USBDUX_CMD_TIMER_RD);
@@ -1084,7 +1084,7 @@ static int usbdux_counter_read(struct comedi_device *dev,
}
counter_read_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret ? ret : insn->n;
}
@@ -1100,7 +1100,7 @@ static int usbdux_counter_write(struct comedi_device *dev,
int ret = 0;
int i;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
devpriv->dux_commands[1] = chan;
@@ -1112,7 +1112,7 @@ static int usbdux_counter_write(struct comedi_device *dev,
break;
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret ? ret : insn->n;
}
@@ -1148,11 +1148,11 @@ static int usbdux_pwm_cancel(struct comedi_device *dev,
struct usbdux_private *devpriv = dev->private;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* unlink only if it is really running */
usbdux_pwm_stop(dev, devpriv->pwm_cmd_running);
ret = send_dux_commands(dev, USBDUX_CMD_PWM_OFF);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -1257,7 +1257,7 @@ static int usbdux_pwm_start(struct comedi_device *dev,
struct usbdux_private *devpriv = dev->private;
int ret = 0;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->pwm_cmd_running)
goto pwm_start_exit;
@@ -1276,7 +1276,7 @@ static int usbdux_pwm_start(struct comedi_device *dev,
devpriv->pwm_cmd_running = 0;
pwm_start_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -1576,7 +1576,7 @@ static int usbdux_auto_attach(struct comedi_device *dev,
if (!devpriv)
return -ENOMEM;
- sema_init(&devpriv->sem, 1);
+ mutex_init(&devpriv->mut);
usb_set_intfdata(intf, devpriv);
@@ -1691,7 +1691,7 @@ static void usbdux_detach(struct comedi_device *dev)
if (!devpriv)
return;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
/* force unlink all urbs */
usbdux_pwm_stop(dev, 1);
@@ -1700,7 +1700,7 @@ static void usbdux_detach(struct comedi_device *dev)
usbdux_free_usb_buffers(dev);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
}
static struct comedi_driver usbdux_driver = {
--
1.9.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 3/4] Staging: comedi: Use mutex instead of semaphore
2015-10-01 16:05 [PATCH 0/4] Use mutex instead of semaphore Ksenija Stanojevic
2015-10-01 16:06 ` [PATCH 1/4] Staging: comedi: " Ksenija Stanojevic
2015-10-01 16:07 ` [PATCH 2/4] " Ksenija Stanojevic
@ 2015-10-01 16:07 ` Ksenija Stanojevic
2015-10-01 16:08 ` [PATCH 4/4] " Ksenija Stanojevic
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: Ksenija Stanojevic @ 2015-10-01 16:07 UTC (permalink / raw)
To: outreachy-kernel; +Cc: Ksenija Stanojevic
Replace binary semaphore with mutex because mutex gives better
performance.
Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
---
drivers/staging/comedi/drivers/usbduxfast.c | 36 ++++++++++++++---------------
1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/drivers/staging/comedi/drivers/usbduxfast.c b/drivers/staging/comedi/drivers/usbduxfast.c
index c6b2a65..10f94ec 100644
--- a/drivers/staging/comedi/drivers/usbduxfast.c
+++ b/drivers/staging/comedi/drivers/usbduxfast.c
@@ -160,7 +160,7 @@ struct usbduxfast_private {
s8 *inbuf;
short int ai_cmd_running; /* asynchronous command is running */
int ignore; /* counter which ignores the first buffers */
- struct semaphore sem;
+ struct mutex mut;
};
/*
@@ -221,9 +221,9 @@ static int usbduxfast_ai_cancel(struct comedi_device *dev,
struct usbduxfast_private *devpriv = dev->private;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
ret = usbduxfast_ai_stop(dev, 1);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -444,7 +444,7 @@ static int usbduxfast_ai_inttrig(struct comedi_device *dev,
if (trig_num != cmd->start_arg)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (!devpriv->ai_cmd_running) {
devpriv->ai_cmd_running = 1;
@@ -452,14 +452,14 @@ static int usbduxfast_ai_inttrig(struct comedi_device *dev,
if (ret < 0) {
dev_err(dev->class_dev, "urbSubmit: err=%d\n", ret);
devpriv->ai_cmd_running = 0;
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
s->async->inttrig = NULL;
} else {
dev_err(dev->class_dev, "ai is already running\n");
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return 1;
}
@@ -472,7 +472,7 @@ static int usbduxfast_ai_cmd(struct comedi_device *dev,
int j, ret;
long steps, steps_tmp;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ai_cmd_running) {
ret = -EBUSY;
goto cmd_exit;
@@ -751,7 +751,7 @@ static int usbduxfast_ai_cmd(struct comedi_device *dev,
}
cmd_exit:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -772,12 +772,12 @@ static int usbduxfast_ai_insn_read(struct comedi_device *dev,
int i, j, n, actual_length;
int ret;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
if (devpriv->ai_cmd_running) {
dev_err(dev->class_dev,
"ai_insn_read not possible, async cmd is running\n");
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return -EBUSY;
}
@@ -799,7 +799,7 @@ static int usbduxfast_ai_insn_read(struct comedi_device *dev,
ret = usbduxfast_send_cmd(dev, SENDADCOMMANDS);
if (ret < 0) {
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -809,7 +809,7 @@ static int usbduxfast_ai_insn_read(struct comedi_device *dev,
&actual_length, 10000);
if (ret < 0) {
dev_err(dev->class_dev, "insn timeout, no data\n");
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
}
@@ -820,13 +820,13 @@ static int usbduxfast_ai_insn_read(struct comedi_device *dev,
&actual_length, 10000);
if (ret < 0) {
dev_err(dev->class_dev, "insn data error: %d\n", ret);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
n = actual_length / sizeof(u16);
if ((n % 16) != 0) {
dev_err(dev->class_dev, "insn data packet corrupted\n");
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return -EINVAL;
}
for (j = chan; (j < n) && (i < insn->n); j = j + 16) {
@@ -835,7 +835,7 @@ static int usbduxfast_ai_insn_read(struct comedi_device *dev,
}
}
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return insn->n;
}
@@ -930,7 +930,7 @@ static int usbduxfast_auto_attach(struct comedi_device *dev,
if (!devpriv)
return -ENOMEM;
- sema_init(&devpriv->sem, 1);
+ mutex_init(&devpriv->mut);
usb_set_intfdata(intf, devpriv);
devpriv->duxbuf = kmalloc(SIZEOFDUXBUF, GFP_KERNEL);
@@ -989,7 +989,7 @@ static void usbduxfast_detach(struct comedi_device *dev)
if (!devpriv)
return;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
usb_set_intfdata(intf, NULL);
@@ -1003,7 +1003,7 @@ static void usbduxfast_detach(struct comedi_device *dev)
kfree(devpriv->duxbuf);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
}
static struct comedi_driver usbduxfast_driver = {
--
1.9.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 4/4] Staging: comedi: Use mutex instead of semaphore
2015-10-01 16:05 [PATCH 0/4] Use mutex instead of semaphore Ksenija Stanojevic
` (2 preceding siblings ...)
2015-10-01 16:07 ` [PATCH 3/4] " Ksenija Stanojevic
@ 2015-10-01 16:08 ` Ksenija Stanojevic
2015-10-01 20:28 ` [Outreachy kernel] [PATCH 0/4] " Arnd Bergmann
2015-10-02 5:17 ` Greg KH
5 siblings, 0 replies; 7+ messages in thread
From: Ksenija Stanojevic @ 2015-10-01 16:08 UTC (permalink / raw)
To: outreachy-kernel; +Cc: Ksenija Stanojevic
Replace binary semaphore with mutex because mutex gives better
performance.
Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
---
drivers/staging/comedi/drivers/ni_usb6501.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/staging/comedi/drivers/ni_usb6501.c b/drivers/staging/comedi/drivers/ni_usb6501.c
index 88de8da..95b537a 100644
--- a/drivers/staging/comedi/drivers/ni_usb6501.c
+++ b/drivers/staging/comedi/drivers/ni_usb6501.c
@@ -166,7 +166,7 @@ enum commands {
struct ni6501_private {
struct usb_endpoint_descriptor *ep_rx;
struct usb_endpoint_descriptor *ep_tx;
- struct semaphore sem;
+ struct mutex mut;
u8 *usb_rx_buf;
u8 *usb_tx_buf;
};
@@ -183,7 +183,7 @@ static int ni6501_port_command(struct comedi_device *dev, int command,
if (command != SET_PORT_DIR && !bitmap)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
switch (command) {
case READ_PORT:
@@ -248,7 +248,7 @@ static int ni6501_port_command(struct comedi_device *dev, int command,
ret = -EINVAL;
}
end:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -265,7 +265,7 @@ static int ni6501_counter_command(struct comedi_device *dev, int command,
if ((command == READ_COUNTER || command == WRITE_COUNTER) && !val)
return -EINVAL;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
switch (command) {
case START_COUNTER:
@@ -338,7 +338,7 @@ static int ni6501_counter_command(struct comedi_device *dev, int command,
ret = -EINVAL;
}
end:
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
return ret;
}
@@ -535,7 +535,7 @@ static int ni6501_auto_attach(struct comedi_device *dev,
if (ret)
return ret;
- sema_init(&devpriv->sem, 1);
+ mutex_init(&devpriv->mut);
usb_set_intfdata(intf, devpriv);
ret = comedi_alloc_subdevices(dev, 2);
@@ -573,14 +573,14 @@ static void ni6501_detach(struct comedi_device *dev)
if (!devpriv)
return;
- down(&devpriv->sem);
+ mutex_lock(&devpriv->mut);
usb_set_intfdata(intf, NULL);
kfree(devpriv->usb_rx_buf);
kfree(devpriv->usb_tx_buf);
- up(&devpriv->sem);
+ mutex_unlock(&devpriv->mut);
}
static struct comedi_driver ni6501_driver = {
--
1.9.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [Outreachy kernel] [PATCH 0/4] Use mutex instead of semaphore
2015-10-01 16:05 [PATCH 0/4] Use mutex instead of semaphore Ksenija Stanojevic
` (3 preceding siblings ...)
2015-10-01 16:08 ` [PATCH 4/4] " Ksenija Stanojevic
@ 2015-10-01 20:28 ` Arnd Bergmann
2015-10-02 5:17 ` Greg KH
5 siblings, 0 replies; 7+ messages in thread
From: Arnd Bergmann @ 2015-10-01 20:28 UTC (permalink / raw)
To: outreachy-kernel; +Cc: Ksenija Stanojevic
On Thursday 01 October 2015 18:05:57 Ksenija Stanojevic wrote:
> This patchset replaces binary semaphore with mutex in comedi drivers.
>
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
>
> Ksenija Stanojevic (4):
> Staging: comedi: Use mutex instead of semaphore
> Staging: comedi: Use mutex instead of semaphore
> Staging: comedi: Use mutex instead of semaphore
> Staging: comedi: Use mutex instead of semaphore
The changes all look good to me, but I think it would be nice to
expand the changelog a bit: in particular, how did you prove for
each file that it is safe to replace the semaphore with a mutex.
Arnd
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [Outreachy kernel] [PATCH 0/4] Use mutex instead of semaphore
2015-10-01 16:05 [PATCH 0/4] Use mutex instead of semaphore Ksenija Stanojevic
` (4 preceding siblings ...)
2015-10-01 20:28 ` [Outreachy kernel] [PATCH 0/4] " Arnd Bergmann
@ 2015-10-02 5:17 ` Greg KH
5 siblings, 0 replies; 7+ messages in thread
From: Greg KH @ 2015-10-02 5:17 UTC (permalink / raw)
To: Ksenija Stanojevic; +Cc: outreachy-kernel
On Thu, Oct 01, 2015 at 06:05:57PM +0200, Ksenija Stanojevic wrote:
> This patchset replaces binary semaphore with mutex in comedi drivers.
>
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
>
> Ksenija Stanojevic (4):
> Staging: comedi: Use mutex instead of semaphore
> Staging: comedi: Use mutex instead of semaphore
> Staging: comedi: Use mutex instead of semaphore
> Staging: comedi: Use mutex instead of semaphore
All 4 of these patches have the same subject, which is not good :(
Please use the driver name in the subject to make them unique, otherwise
it looks like something went wrong and you sent the same patch 4 times.
thanks,
greg k-h
^ permalink raw reply [flat|nested] 7+ messages in thread