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

[Suren Baghdasaryan]

On Mon, Aug 3, 2020 at 9:12 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> 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.

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