On Thu, Jan 28, 2021 at 1:55 PM Randy Dunlap rdunlap@infradead.org wrote:
On 1/28/21 10:24 AM, Kalesh Singh wrote:
The dmabuf inode number allows userspace to uniquely identify the buffer and avoids a dependency on /proc/<pid>/fd/* when accounting per-process DMA buffer sizes.
Signed-off-by: Kalesh Singh kaleshsingh@google.com
drivers/dma-buf/dma-buf.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 9ad6397aaa97..d869099ede83 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -414,6 +414,7 @@ static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file) { struct dma_buf *dmabuf = file->private_data;
seq_printf(m, "dmabuf_inode_no:\t%lu\n", file_inode(file)->i_ino); seq_printf(m, "size:\t%zu\n", dmabuf->size); /* Don't count the temporary reference taken inside procfs seq_show */ seq_printf(m, "count:\t%ld\n", file_count(dmabuf->file) - 1);[resending; hopefully the first one didn't go anywhere]
Hi,
The subject is a little confusing. It seems to say that the dmabuf inode no is being added to /proc/<pid>/fdinfo, but looking at the code, it is being added to /proc/dmabuf (or /proc/<pid>/dmabuf).
Please clarify.
and is the /proc file format documented anywhere?
Hi Randy,
The patch adds the inode number in /proc/<pid>/fdinfo/* and /proc/<pid>/task/<tid>/fdinfo/* for FDs corresponding to dmabufs. fdinfo is documented in proc man pages, but it doesn't include the dmabuf specific fields, so this will need to be updated. I hope this clarifies.
Thanks, Kalesh
thanks.
-- ~Randy