From: Dean Anderson <linux-dev@sensoray.com>
To: hverkuil@xs4all.nl, linux-dev@sensoray.com, linux-media@vger.kernel.org
Subject: [PATCH] s2255drv: dynamic memory allocation efficiency fix
Date: Wed, 5 Feb 2014 10:43:51 -0800 [thread overview]
Message-ID: <1391625831-3503-1-git-send-email-linux-dev@sensoray.com> (raw)
Driver was allocating a kernel buffer each time it was sending a command.
It is better to allocate this buffer once at startup.
Signed-off-by: Dean Anderson <linux-dev@sensoray.com>
---
drivers/media/usb/s2255/s2255drv.c | 67 ++++++++++++++++++++----------------
1 file changed, 37 insertions(+), 30 deletions(-)
diff --git a/drivers/media/usb/s2255/s2255drv.c b/drivers/media/usb/s2255/s2255drv.c
index 517901b..4c483ad 100644
--- a/drivers/media/usb/s2255/s2255drv.c
+++ b/drivers/media/usb/s2255/s2255drv.c
@@ -260,6 +260,7 @@ struct s2255_dev {
atomic_t num_channels;
int frames;
struct mutex lock; /* channels[].vdev.lock */
+ struct mutex cmdlock; /* protects cmdbuf */
struct usb_device *udev;
struct usb_interface *interface;
u8 read_endpoint;
@@ -273,6 +274,8 @@ struct s2255_dev {
/* dsp firmware version (f2255usb.bin) */
int dsp_fw_ver;
u16 pid; /* product id */
+#define S2255_CMDBUF_SIZE 512
+ __le32 *cmdbuf;
};
static inline struct s2255_dev *to_s2255_dev(struct v4l2_device *v4l2_dev)
@@ -1121,11 +1124,12 @@ static int s2255_set_mode(struct s2255_vc *vc,
struct s2255_mode *mode)
{
int res;
- __le32 *buffer;
unsigned long chn_rev;
struct s2255_dev *dev = to_s2255_dev(vc->vdev.v4l2_dev);
int i;
+ __le32 *buffer = dev->cmdbuf;
+ mutex_lock(&dev->cmdlock);
chn_rev = G_chnmap[vc->idx];
dprintk(dev, 3, "%s channel: %d\n", __func__, vc->idx);
/* if JPEG, set the quality */
@@ -1139,11 +1143,6 @@ static int s2255_set_mode(struct s2255_vc *vc,
vc->mode = *mode;
vc->req_image_size = get_transfer_size(mode);
dprintk(dev, 1, "%s: reqsize %ld\n", __func__, vc->req_image_size);
- buffer = kzalloc(512, GFP_KERNEL);
- if (buffer == NULL) {
- dev_err(&dev->udev->dev, "out of mem\n");
- return -ENOMEM;
- }
/* set the mode */
buffer[0] = IN_DATA_TOKEN;
buffer[1] = (__le32) cpu_to_le32(chn_rev);
@@ -1154,7 +1153,6 @@ static int s2255_set_mode(struct s2255_vc *vc,
res = s2255_write_config(dev->udev, (unsigned char *)buffer, 512);
if (debug)
s2255_print_cfg(dev, mode);
- kfree(buffer);
/* wait at least 3 frames before continuing */
if (mode->restart) {
wait_event_timeout(vc->wait_setmode,
@@ -1168,22 +1166,20 @@ static int s2255_set_mode(struct s2255_vc *vc,
/* clear the restart flag */
vc->mode.restart = 0;
dprintk(dev, 1, "%s chn %d, result: %d\n", __func__, vc->idx, res);
+ mutex_unlock(&dev->cmdlock);
return res;
}
static int s2255_cmd_status(struct s2255_vc *vc, u32 *pstatus)
{
int res;
- __le32 *buffer;
u32 chn_rev;
struct s2255_dev *dev = to_s2255_dev(vc->vdev.v4l2_dev);
+ __le32 *buffer = dev->cmdbuf;
+
+ mutex_lock(&dev->cmdlock);
chn_rev = G_chnmap[vc->idx];
dprintk(dev, 4, "%s chan %d\n", __func__, vc->idx);
- buffer = kzalloc(512, GFP_KERNEL);
- if (buffer == NULL) {
- dev_err(&dev->udev->dev, "out of mem\n");
- return -ENOMEM;
- }
/* form the get vid status command */
buffer[0] = IN_DATA_TOKEN;
buffer[1] = (__le32) cpu_to_le32(chn_rev);
@@ -1191,7 +1187,6 @@ static int s2255_cmd_status(struct s2255_vc *vc, u32 *pstatus)
*pstatus = 0;
vc->vidstatus_ready = 0;
res = s2255_write_config(dev->udev, (unsigned char *)buffer, 512);
- kfree(buffer);
wait_event_timeout(vc->wait_vidstatus,
(vc->vidstatus_ready != 0),
msecs_to_jiffies(S2255_VIDSTATUS_TIMEOUT));
@@ -1201,6 +1196,7 @@ static int s2255_cmd_status(struct s2255_vc *vc, u32 *pstatus)
}
*pstatus = vc->vidstatus;
dprintk(dev, 4, "%s, vid status %d\n", __func__, *pstatus);
+ mutex_unlock(&dev->cmdlock);
return res;
}
@@ -1724,6 +1720,7 @@ static void s2255_destroy(struct s2255_dev *dev)
mutex_destroy(&dev->lock);
usb_put_dev(dev->udev);
v4l2_device_unregister(&dev->v4l2_dev);
+ kfree(dev->cmdbuf);
kfree(dev);
}
@@ -2350,18 +2347,14 @@ static int s2255_start_readpipe(struct s2255_dev *dev)
/* starts acquisition process */
static int s2255_start_acquire(struct s2255_vc *vc)
{
- unsigned char *buffer;
int res;
unsigned long chn_rev;
int j;
struct s2255_dev *dev = to_s2255_dev(vc->vdev.v4l2_dev);
- chn_rev = G_chnmap[vc->idx];
- buffer = kzalloc(512, GFP_KERNEL);
- if (buffer == NULL) {
- dev_err(&dev->udev->dev, "out of mem\n");
- return -ENOMEM;
- }
+ __le32 *buffer = dev->cmdbuf;
+ mutex_lock(&dev->cmdlock);
+ chn_rev = G_chnmap[vc->idx];
vc->last_frame = -1;
vc->bad_payload = 0;
vc->cur_frame = 0;
@@ -2371,24 +2364,26 @@ static int s2255_start_acquire(struct s2255_vc *vc)
}
/* send the start command */
- *(__le32 *) buffer = IN_DATA_TOKEN;
- *((__le32 *) buffer + 1) = (__le32) cpu_to_le32(chn_rev);
- *((__le32 *) buffer + 2) = CMD_START;
+ buffer[0] = IN_DATA_TOKEN;
+ buffer[1] = (__le32) cpu_to_le32(chn_rev);
+ buffer[2] = CMD_START;
res = s2255_write_config(dev->udev, (unsigned char *)buffer, 512);
if (res != 0)
dev_err(&dev->udev->dev, "CMD_START error\n");
dprintk(dev, 2, "start acquire exit[%d] %d\n", vc->idx, res);
- kfree(buffer);
+ mutex_unlock(&dev->cmdlock);
return 0;
}
static int s2255_stop_acquire(struct s2255_vc *vc)
{
- unsigned char *buffer;
int res;
unsigned long chn_rev;
struct s2255_dev *dev = to_s2255_dev(vc->vdev.v4l2_dev);
+ __le32 *buffer = dev->cmdbuf;
+
+ mutex_lock(&dev->cmdlock);
chn_rev = G_chnmap[vc->idx];
buffer = kzalloc(512, GFP_KERNEL);
if (buffer == NULL) {
@@ -2396,15 +2391,17 @@ static int s2255_stop_acquire(struct s2255_vc *vc)
return -ENOMEM;
}
/* send the stop command */
- *(__le32 *) buffer = IN_DATA_TOKEN;
- *((__le32 *) buffer + 1) = (__le32) cpu_to_le32(chn_rev);
- *((__le32 *) buffer + 2) = CMD_STOP;
+ buffer[0] = IN_DATA_TOKEN;
+ buffer[1] = (__le32) cpu_to_le32(chn_rev);
+ buffer[2] = CMD_STOP;
+
res = s2255_write_config(dev->udev, (unsigned char *)buffer, 512);
if (res != 0)
dev_err(&dev->udev->dev, "CMD_STOP error\n");
- kfree(buffer);
+
vc->b_acquire = 0;
dprintk(dev, 4, "%s: chn %d, res %d\n", __func__, vc->idx, res);
+ mutex_unlock(&dev->cmdlock);
return res;
}
@@ -2451,18 +2448,27 @@ static int s2255_probe(struct usb_interface *interface,
int retval = -ENOMEM;
__le32 *pdata;
int fw_size;
+
/* allocate memory for our device state and initialize it to zero */
dev = kzalloc(sizeof(struct s2255_dev), GFP_KERNEL);
if (dev == NULL) {
s2255_dev_err(&interface->dev, "out of memory\n");
return -ENOMEM;
}
+
+ dev->cmdbuf = kzalloc(S2255_CMDBUF_SIZE, GFP_KERNEL);
+ if (dev->cmdbuf == NULL) {
+ s2255_dev_err(&interface->dev, "out of memory\n");
+ return -ENOMEM;
+ }
+
atomic_set(&dev->num_channels, 0);
dev->pid = le16_to_cpu(id->idProduct);
dev->fw_data = kzalloc(sizeof(struct s2255_fw), GFP_KERNEL);
if (!dev->fw_data)
goto errorFWDATA1;
mutex_init(&dev->lock);
+ mutex_init(&dev->cmdlock);
/* grab usb_device and save it */
dev->udev = usb_get_dev(interface_to_usbdev(interface));
if (dev->udev == NULL) {
@@ -2568,6 +2574,7 @@ errorUDEV:
kfree(dev->fw_data);
mutex_destroy(&dev->lock);
errorFWDATA1:
+ kfree(dev->cmdbuf);
kfree(dev);
pr_warn("Sensoray 2255 driver load failed: 0x%x\n", retval);
return retval;
--
1.7.9.5
reply other threads:[~2014-02-05 19:31 UTC|newest]
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