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@xxxxxxxxxx> > [minor fixes on init and warning fix] > Signed-off-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx> > --- > 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. > +{ > + 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. > + > +#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 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html