Merge branches 'dma-debug/fixes' and 'dma-debug/driver-filter' into dma-debug/2.6.31
commit
bdc2911cde
|
@ -704,12 +704,24 @@ this directory the following files can currently be found:
|
||||||
The current number of free dma_debug_entries
|
The current number of free dma_debug_entries
|
||||||
in the allocator.
|
in the allocator.
|
||||||
|
|
||||||
|
dma-api/driver-filter
|
||||||
|
You can write a name of a driver into this file
|
||||||
|
to limit the debug output to requests from that
|
||||||
|
particular driver. Write an empty string to
|
||||||
|
that file to disable the filter and see
|
||||||
|
all errors again.
|
||||||
|
|
||||||
If you have this code compiled into your kernel it will be enabled by default.
|
If you have this code compiled into your kernel it will be enabled by default.
|
||||||
If you want to boot without the bookkeeping anyway you can provide
|
If you want to boot without the bookkeeping anyway you can provide
|
||||||
'dma_debug=off' as a boot parameter. This will disable DMA-API debugging.
|
'dma_debug=off' as a boot parameter. This will disable DMA-API debugging.
|
||||||
Notice that you can not enable it again at runtime. You have to reboot to do
|
Notice that you can not enable it again at runtime. You have to reboot to do
|
||||||
so.
|
so.
|
||||||
|
|
||||||
|
If you want to see debug messages only for a special device driver you can
|
||||||
|
specify the dma_debug_driver=<drivername> parameter. This will enable the
|
||||||
|
driver filter at boot time. The debug code will only print errors for that
|
||||||
|
driver afterwards. This filter can be disabled or changed later using debugfs.
|
||||||
|
|
||||||
When the code disables itself at runtime this is most likely because it ran
|
When the code disables itself at runtime this is most likely because it ran
|
||||||
out of dma_debug_entries. These entries are preallocated at boot. The number
|
out of dma_debug_entries. These entries are preallocated at boot. The number
|
||||||
of preallocated entries is defined per architecture. If it is too low for you
|
of preallocated entries is defined per architecture. If it is too low for you
|
||||||
|
|
|
@ -646,6 +646,13 @@ and is between 256 and 4096 characters. It is defined in the file
|
||||||
DMA-API debugging code disables itself because the
|
DMA-API debugging code disables itself because the
|
||||||
architectural default is too low.
|
architectural default is too low.
|
||||||
|
|
||||||
|
dma_debug_driver=<driver_name>
|
||||||
|
With this option the DMA-API debugging driver
|
||||||
|
filter feature can be enabled at boot time. Just
|
||||||
|
pass the driver to filter for as the parameter.
|
||||||
|
The filter can be disabled or changed to another
|
||||||
|
driver later using sysfs.
|
||||||
|
|
||||||
dscc4.setup= [NET]
|
dscc4.setup= [NET]
|
||||||
|
|
||||||
dtc3181e= [HW,SCSI]
|
dtc3181e= [HW,SCSI]
|
||||||
|
|
167
lib/dma-debug.c
167
lib/dma-debug.c
|
@ -23,9 +23,11 @@
|
||||||
#include <linux/dma-debug.h>
|
#include <linux/dma-debug.h>
|
||||||
#include <linux/spinlock.h>
|
#include <linux/spinlock.h>
|
||||||
#include <linux/debugfs.h>
|
#include <linux/debugfs.h>
|
||||||
|
#include <linux/uaccess.h>
|
||||||
#include <linux/device.h>
|
#include <linux/device.h>
|
||||||
#include <linux/types.h>
|
#include <linux/types.h>
|
||||||
#include <linux/sched.h>
|
#include <linux/sched.h>
|
||||||
|
#include <linux/ctype.h>
|
||||||
#include <linux/list.h>
|
#include <linux/list.h>
|
||||||
#include <linux/slab.h>
|
#include <linux/slab.h>
|
||||||
|
|
||||||
|
@ -98,6 +100,16 @@ static struct dentry *show_all_errors_dent __read_mostly;
|
||||||
static struct dentry *show_num_errors_dent __read_mostly;
|
static struct dentry *show_num_errors_dent __read_mostly;
|
||||||
static struct dentry *num_free_entries_dent __read_mostly;
|
static struct dentry *num_free_entries_dent __read_mostly;
|
||||||
static struct dentry *min_free_entries_dent __read_mostly;
|
static struct dentry *min_free_entries_dent __read_mostly;
|
||||||
|
static struct dentry *filter_dent __read_mostly;
|
||||||
|
|
||||||
|
/* per-driver filter related state */
|
||||||
|
|
||||||
|
#define NAME_MAX_LEN 64
|
||||||
|
|
||||||
|
static char current_driver_name[NAME_MAX_LEN] __read_mostly;
|
||||||
|
static struct device_driver *current_driver __read_mostly;
|
||||||
|
|
||||||
|
static DEFINE_RWLOCK(driver_name_lock);
|
||||||
|
|
||||||
static const char *type2name[4] = { "single", "page",
|
static const char *type2name[4] = { "single", "page",
|
||||||
"scather-gather", "coherent" };
|
"scather-gather", "coherent" };
|
||||||
|
@ -133,9 +145,48 @@ static inline void dump_entry_trace(struct dma_debug_entry *entry)
|
||||||
#endif
|
#endif
|
||||||
}
|
}
|
||||||
|
|
||||||
|
static bool driver_filter(struct device *dev)
|
||||||
|
{
|
||||||
|
/* driver filter off */
|
||||||
|
if (likely(!current_driver_name[0]))
|
||||||
|
return true;
|
||||||
|
|
||||||
|
/* driver filter on and initialized */
|
||||||
|
if (current_driver && dev->driver == current_driver)
|
||||||
|
return true;
|
||||||
|
|
||||||
|
/* driver filter on but not yet initialized */
|
||||||
|
if (!current_driver && current_driver_name[0]) {
|
||||||
|
struct device_driver *drv = get_driver(dev->driver);
|
||||||
|
unsigned long flags;
|
||||||
|
bool ret = false;
|
||||||
|
|
||||||
|
if (!drv)
|
||||||
|
return false;
|
||||||
|
|
||||||
|
/* lock to protect against change of current_driver_name */
|
||||||
|
read_lock_irqsave(&driver_name_lock, flags);
|
||||||
|
|
||||||
|
if (drv->name &&
|
||||||
|
strncmp(current_driver_name, drv->name,
|
||||||
|
NAME_MAX_LEN-1) == 0) {
|
||||||
|
current_driver = drv;
|
||||||
|
ret = true;
|
||||||
|
}
|
||||||
|
|
||||||
|
read_unlock_irqrestore(&driver_name_lock, flags);
|
||||||
|
put_driver(drv);
|
||||||
|
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
#define err_printk(dev, entry, format, arg...) do { \
|
#define err_printk(dev, entry, format, arg...) do { \
|
||||||
error_count += 1; \
|
error_count += 1; \
|
||||||
if (show_all_errors || show_num_errors > 0) { \
|
if (driver_filter(dev) && \
|
||||||
|
(show_all_errors || show_num_errors > 0)) { \
|
||||||
WARN(1, "%s %s: " format, \
|
WARN(1, "%s %s: " format, \
|
||||||
dev_driver_string(dev), \
|
dev_driver_string(dev), \
|
||||||
dev_name(dev) , ## arg); \
|
dev_name(dev) , ## arg); \
|
||||||
|
@ -412,6 +463,97 @@ out_err:
|
||||||
return -ENOMEM;
|
return -ENOMEM;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
static ssize_t filter_read(struct file *file, char __user *user_buf,
|
||||||
|
size_t count, loff_t *ppos)
|
||||||
|
{
|
||||||
|
unsigned long flags;
|
||||||
|
char buf[NAME_MAX_LEN + 1];
|
||||||
|
int len;
|
||||||
|
|
||||||
|
if (!current_driver_name[0])
|
||||||
|
return 0;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* We can't copy to userspace directly because current_driver_name can
|
||||||
|
* only be read under the driver_name_lock with irqs disabled. So
|
||||||
|
* create a temporary copy first.
|
||||||
|
*/
|
||||||
|
read_lock_irqsave(&driver_name_lock, flags);
|
||||||
|
len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name);
|
||||||
|
read_unlock_irqrestore(&driver_name_lock, flags);
|
||||||
|
|
||||||
|
return simple_read_from_buffer(user_buf, count, ppos, buf, len);
|
||||||
|
}
|
||||||
|
|
||||||
|
static ssize_t filter_write(struct file *file, const char __user *userbuf,
|
||||||
|
size_t count, loff_t *ppos)
|
||||||
|
{
|
||||||
|
unsigned long flags;
|
||||||
|
char buf[NAME_MAX_LEN];
|
||||||
|
size_t len = NAME_MAX_LEN - 1;
|
||||||
|
int i;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* We can't copy from userspace directly. Access to
|
||||||
|
* current_driver_name is protected with a write_lock with irqs
|
||||||
|
* disabled. Since copy_from_user can fault and may sleep we
|
||||||
|
* need to copy to temporary buffer first
|
||||||
|
*/
|
||||||
|
len = min(count, len);
|
||||||
|
if (copy_from_user(buf, userbuf, len))
|
||||||
|
return -EFAULT;
|
||||||
|
|
||||||
|
buf[len] = 0;
|
||||||
|
|
||||||
|
write_lock_irqsave(&driver_name_lock, flags);
|
||||||
|
|
||||||
|
/* Now handle the string we got from userspace very carefully.
|
||||||
|
* The rules are:
|
||||||
|
* - only use the first token we got
|
||||||
|
* - token delimiter is everything looking like a space
|
||||||
|
* character (' ', '\n', '\t' ...)
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
if (!isalnum(buf[0])) {
|
||||||
|
/*
|
||||||
|
If the first character userspace gave us is not
|
||||||
|
* alphanumerical then assume the filter should be
|
||||||
|
* switched off.
|
||||||
|
*/
|
||||||
|
if (current_driver_name[0])
|
||||||
|
printk(KERN_INFO "DMA-API: switching off dma-debug "
|
||||||
|
"driver filter\n");
|
||||||
|
current_driver_name[0] = 0;
|
||||||
|
current_driver = NULL;
|
||||||
|
goto out_unlock;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Now parse out the first token and use it as the name for the
|
||||||
|
* driver to filter for.
|
||||||
|
*/
|
||||||
|
for (i = 0; i < NAME_MAX_LEN; ++i) {
|
||||||
|
current_driver_name[i] = buf[i];
|
||||||
|
if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0)
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
current_driver_name[i] = 0;
|
||||||
|
current_driver = NULL;
|
||||||
|
|
||||||
|
printk(KERN_INFO "DMA-API: enable driver filter for driver [%s]\n",
|
||||||
|
current_driver_name);
|
||||||
|
|
||||||
|
out_unlock:
|
||||||
|
write_unlock_irqrestore(&driver_name_lock, flags);
|
||||||
|
|
||||||
|
return count;
|
||||||
|
}
|
||||||
|
|
||||||
|
const struct file_operations filter_fops = {
|
||||||
|
.read = filter_read,
|
||||||
|
.write = filter_write,
|
||||||
|
};
|
||||||
|
|
||||||
static int dma_debug_fs_init(void)
|
static int dma_debug_fs_init(void)
|
||||||
{
|
{
|
||||||
dma_debug_dent = debugfs_create_dir("dma-api", NULL);
|
dma_debug_dent = debugfs_create_dir("dma-api", NULL);
|
||||||
|
@ -455,6 +597,11 @@ static int dma_debug_fs_init(void)
|
||||||
if (!min_free_entries_dent)
|
if (!min_free_entries_dent)
|
||||||
goto out_err;
|
goto out_err;
|
||||||
|
|
||||||
|
filter_dent = debugfs_create_file("driver_filter", 0644,
|
||||||
|
dma_debug_dent, NULL, &filter_fops);
|
||||||
|
if (!filter_dent)
|
||||||
|
goto out_err;
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
|
|
||||||
out_err:
|
out_err:
|
||||||
|
@ -1044,3 +1191,21 @@ void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
|
||||||
}
|
}
|
||||||
EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
|
EXPORT_SYMBOL(debug_dma_sync_sg_for_device);
|
||||||
|
|
||||||
|
static int __init dma_debug_driver_setup(char *str)
|
||||||
|
{
|
||||||
|
int i;
|
||||||
|
|
||||||
|
for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) {
|
||||||
|
current_driver_name[i] = *str;
|
||||||
|
if (*str == 0)
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (current_driver_name[0])
|
||||||
|
printk(KERN_INFO "DMA-API: enable driver filter for "
|
||||||
|
"driver [%s]\n", current_driver_name);
|
||||||
|
|
||||||
|
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
__setup("dma_debug_driver=", dma_debug_driver_setup);
|
||||||
|
|
Loading…
Reference in New Issue