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

From: Matthew Wilcox
Date: Mon Aug 03 2020 - 12:12:43 EST


On Mon, Aug 03, 2020 at 09:00:00AM -0700, Suren Baghdasaryan wrote:
> On Mon, Aug 3, 2020 at 8:41 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
> >
> > On Mon, Aug 03, 2020 at 02:47:19PM +0000, Kalesh Singh wrote:
> > > +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.