dma-debug: add debugfs interface

Impact: add debugfs interface for configuring DMA-API debugging

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This commit is contained in:
Joerg Roedel 2009-01-09 13:13:27 +01:00
parent 59d3daafa1
commit 788dcfa6f1

View file

@ -19,6 +19,7 @@
#include <linux/dma-debug.h>
#include <linux/spinlock.h>
#include <linux/debugfs.h>
#include <linux/types.h>
#include <linux/list.h>
#include <linux/slab.h>
@ -61,12 +62,29 @@ static DEFINE_SPINLOCK(free_entries_lock);
/* Global disable flag - will be set in case of an error */
static bool global_disable __read_mostly;
/* Global error count */
static u32 error_count;
/* Global error show enable*/
static u32 show_all_errors __read_mostly;
/* Number of errors to show */
static u32 show_num_errors = 1;
static u32 num_free_entries;
static u32 min_free_entries;
/* number of preallocated entries requested by kernel cmdline */
static u32 req_entries;
/* debugfs dentry's for the stuff above */
static struct dentry *dma_debug_dent __read_mostly;
static struct dentry *global_disable_dent __read_mostly;
static struct dentry *error_count_dent __read_mostly;
static struct dentry *show_all_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 *min_free_entries_dent __read_mostly;
/*
* Hash related functions
*
@ -241,6 +259,58 @@ out_err:
return -ENOMEM;
}
static int dma_debug_fs_init(void)
{
dma_debug_dent = debugfs_create_dir("dma-api", NULL);
if (!dma_debug_dent) {
printk(KERN_ERR "DMA-API: can not create debugfs directory\n");
return -ENOMEM;
}
global_disable_dent = debugfs_create_bool("disabled", 0444,
dma_debug_dent,
(u32 *)&global_disable);
if (!global_disable_dent)
goto out_err;
error_count_dent = debugfs_create_u32("error_count", 0444,
dma_debug_dent, &error_count);
if (!error_count_dent)
goto out_err;
show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
dma_debug_dent,
&show_all_errors);
if (!show_all_errors_dent)
goto out_err;
show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
dma_debug_dent,
&show_num_errors);
if (!show_num_errors_dent)
goto out_err;
num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
dma_debug_dent,
&num_free_entries);
if (!num_free_entries_dent)
goto out_err;
min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
dma_debug_dent,
&min_free_entries);
if (!min_free_entries_dent)
goto out_err;
return 0;
out_err:
debugfs_remove_recursive(dma_debug_dent);
return -ENOMEM;
}
/*
* Let the architectures decide how many entries should be preallocated.
*/
@ -256,6 +326,14 @@ void dma_debug_init(u32 num_entries)
dma_entry_hash[i].lock = SPIN_LOCK_UNLOCKED;
}
if (dma_debug_fs_init() != 0) {
printk(KERN_ERR "DMA-API: error creating debugfs entries "
"- disabling\n");
global_disable = true;
return;
}
if (req_entries)
num_entries = req_entries;