dma-debug: add debugfs interface
Impact: add debugfs interface for configuring DMA-API debugging
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/lib/dma-debug.c b/lib/dma-debug.c
index 2ede463..20d6cdb 100644
--- a/lib/dma-debug.c
+++ b/lib/dma-debug.c
@@ -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 @@
/* 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 @@
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 @@
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;