Re: bug fix for registers debugfs file implementation [RFC]

[Mark Brown]

On Mon, Apr 24, 2017 at 10:02:31AM +0100, Charles Keepax wrote:
> On Sat, Apr 22, 2017 at 01:28:15PM -0700, Variksla wrote:
> > > On Apr 21, 2017, at 10:27 AM, Mark Brown <broonie@xxxxxxxxxx> wrote:

> > > If I remember correctly this is done the way it is because seq_file has
> > > to iterate through the entire file to get to the point being read by the
> > > application.  This is a *very* big overhead for some applications (like
> > > monitoring some registers to see what they're doing) on bigger devices,

> > Wondering why would the user space application be monitoring the registers?

> We do have tooling that accesses and occasionally monitors
> registers using the debugfs files. It is often used by hardware
> types while testing/debugging issues. And as Mark points out

Even without an actual program explicitly written for it interactive
monitoring of the register map can be done by a person as well which is
just as much of an application (and the major point of the file).

Attachment: signature.asc
Description: PGP signature