Re: [PATCH 2/2] dmabuf/tracing: Add dma-buf trace events

On Mon, Aug 3, 2020 at 9:12 AM Matthew Wilcox [off-list ref] wrote:

On Mon, Aug 03, 2020 at 09:00:00AM -0700, Suren Baghdasaryan wrote:

quoted

On Mon, Aug 3, 2020 at 8:41 AM Matthew Wilcox [off-list ref] wrote:

quoted

On Mon, Aug 03, 2020 at 02:47:19PM +0000, Kalesh Singh wrote:

quoted

+static void dma_buf_fd_install(int fd, struct file *filp)
+{
+     trace_dma_buf_fd_ref_inc(current, filp);
+}

You're adding a new file_operation in order to just add a new tracepoint?
NACK.

Hi Matthew,
The plan is to attach a BPF to this tracepoint in order to track
dma-buf users. If you feel this is an overkill, what would you suggest
as an alternative?

I'm sure BPF can attach to fd_install and filter on file->f_ops belonging
to dma_buf, for example.

Sounds like a workable solution. Will explore that direction. Thanks Matthew!