Hi Laurent!
Thanks for the review:
On 27 March 2013 05:38, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:
Hi Sumit,
Thanks for the patch.
On Monday 25 March 2013 16:50:46 Sumit Semwal wrote:
Add debugfs support to make it easier to print debug information about the dma-buf buffers.
Cc: Dave Airlie airlied@redhat.com [minor fixes on init and warning fix] Signed-off-by: Sumit Semwal sumit.semwal@linaro.org
changes since v1:
- fixes on init and warnings as reported and corrected by Dave Airlie.
- add locking while walking attachment list - reported by Daniel Vetter.
drivers/base/dma-buf.c | 162 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/dma-buf.h | 5 +- 2 files changed, 166 insertions(+), 1 deletion(-)
diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c index d89102a..7d867ed 100644 --- a/drivers/base/dma-buf.c +++ b/drivers/base/dma-buf.c @@ -27,9 +27,18 @@ #include <linux/dma-buf.h> #include <linux/anon_inodes.h> #include <linux/export.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h>
static inline int is_dma_buf_file(struct file *);
+struct dma_buf_list {
struct list_head head;struct mutex lock;+};
+static struct dma_buf_list db_list;
static int dma_buf_release(struct inode *inode, struct file *file) { struct dma_buf *dmabuf; @@ -42,6 +51,11 @@ static int dma_buf_release(struct inode *inode, struct file *file) BUG_ON(dmabuf->vmapping_counter);
dmabuf->ops->release(dmabuf);
mutex_lock(&db_list.lock);list_del(&dmabuf->list_node);mutex_unlock(&db_list.lock);kfree(dmabuf); return 0;} @@ -125,6 +139,10 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops, mutex_init(&dmabuf->lock); INIT_LIST_HEAD(&dmabuf->attachments);
mutex_lock(&db_list.lock);list_add(&dmabuf->list_node, &db_list.head);mutex_unlock(&db_list.lock);return dmabuf;} EXPORT_SYMBOL_GPL(dma_buf_export_named); @@ -551,3 +569,147 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr) mutex_unlock(&dmabuf->lock); } EXPORT_SYMBOL_GPL(dma_buf_vunmap);
+static int dma_buf_init_debugfs(void); +static void dma_buf_uninit_debugfs(void);
+static int __init dma_buf_init(void) +{
mutex_init(&db_list.lock);INIT_LIST_HEAD(&db_list.head);dma_buf_init_debugfs();return 0;+}
+subsys_initcall(dma_buf_init);
+static void __exit dma_buf_deinit(void)
This function is never called.
You're right; it's missing an __exitcall() - I will add it!
+{
dma_buf_uninit_debugfs();+}
If you moved those two functions at the end of the file you could get rid of the forward declarations above.
Sure - will do that.
+#ifdef CONFIG_DEBUG_FS +static int dma_buf_describe(struct seq_file *s) +{
int ret;struct dma_buf *buf_obj;struct dma_buf_attachment *attach_obj;int count = 0, attach_count;size_t size = 0;ret = mutex_lock_interruptible(&db_list.lock);if (ret)return ret;seq_printf(s, "\nDma-buf Objects:\n");seq_printf(s, "\texp_name\tsize\tflags\tmode\tcount\n");list_for_each_entry(buf_obj, &db_list.head, list_node) {ret = mutex_lock_interruptible(&buf_obj->lock);if (ret) {seq_printf(s,"\tERROR locking buffer object: skipping\n");goto skip_buffer;}seq_printf(s, "\t");seq_printf(s, "\t%s\t%08zu\t%08x\t%08x\t%08d\n",buf_obj->exp_name, buf_obj->size,buf_obj->file->f_flags, buf_obj->file->f_mode,buf_obj->file->f_count.counter);seq_printf(s, "\t\tAttached Devices:\n");attach_count = 0;list_for_each_entry(attach_obj, &buf_obj->attachments, node) {seq_printf(s, "\t\t");seq_printf(s, "%s\n", attach_obj->dev->init_name);attach_count++;}seq_printf(s, "\n\t\tTotal %d devices attached\n",attach_count);count++;size += buf_obj->size;+skip_buffer:
mutex_unlock(&buf_obj->lock);}seq_printf(s, "\nTotal %d objects, %zu bytes\n", count, size);mutex_unlock(&db_list.lock);return 0;+}
+static int dma_buf_show(struct seq_file *s, void *unused) +{
void (*func)(struct seq_file *) = s->private;func(s);return 0;+}
+static int dma_buf_debug_open(struct inode *inode, struct file *file) +{
return single_open(file, dma_buf_show, inode->i_private);+}
+static const struct file_operations dma_buf_debug_fops = {
.open = dma_buf_debug_open,.read = seq_read,.llseek = seq_lseek,.release = single_release,+};
+static struct dentry *dma_buf_debugfs_dir;
+static int dma_buf_init_debugfs(void) +{
int err = 0;dma_buf_debugfs_dir = debugfs_create_dir("dma_buf", NULL);if (IS_ERR(dma_buf_debugfs_dir)) {err = PTR_ERR(dma_buf_debugfs_dir);dma_buf_debugfs_dir = NULL;return err;}err = dma_buf_debugfs_create_file("bufinfo", dma_buf_describe);if (err)pr_debug("dma_buf: debugfs: failed to create node bufinfo\n");return err;+}
+static void dma_buf_uninit_debugfs(void) +{
if (dma_buf_debugfs_dir)debugfs_remove_recursive(dma_buf_debugfs_dir);+}
+int dma_buf_debugfs_create_file(const char *name,
int (*write)(struct seq_file *))+{
struct dentry *d;d = debugfs_create_file(name, S_IRUGO, dma_buf_debugfs_dir,write, &dma_buf_debug_fops);if (IS_ERR(d))return PTR_ERR(d);return 0;+} +#else +static inline int dma_buf_init_debugfs(void) +{
return 0;+} +static inline void dma_buf_uninit_debugfs(void) +{ +} +#endif diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 6f55c04..dfac5ed 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -113,6 +113,7 @@ struct dma_buf_ops {
- @attachments: list of dma_buf_attachment that denotes all devices
attached. * @ops: dma_buf_ops associated with this buffer object.
- @exp_name: name of the exporter; useful for debugging.
*/
- @list_node: node for dma_buf accounting and debugging.
- @priv: exporter specific private data for this buffer object.
struct dma_buf { @@ -125,6 +126,7 @@ struct dma_buf { unsigned vmapping_counter; void *vmap_ptr; const char *exp_name;
struct list_head list_node; void *priv;};
@@ -192,5 +194,6 @@ int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, unsigned long); void *dma_buf_vmap(struct dma_buf *); void dma_buf_vunmap(struct dma_buf *, void *vaddr);
+int dma_buf_debugfs_create_file(const char *name,
int (*write)(struct seq_file *));This function is only called internally from the same file, could it be declared as static ?
#endif /* __DMA_BUF_H__ */
-- Regards,
Laurent Pinchart
-- Thanks and regards, Sumit Semwal