Re: [PATCH RESEND v9 2/3] fuse: add optional kernel-enforced timeout for requests

[Sergey Senozhatsky <senozhatsky@chromium.org>]

On (24/12/05 15:29), Joanne Koong wrote:
> On Wed, Dec 4, 2024 at 5:47 AM Sergey Senozhatsky
> <senozhatsky@chromium.org> wrote:
> >
> > On (24/11/14 11:13), Joanne Koong wrote:
> > >
> > > +static bool request_expired(struct fuse_conn *fc, struct fuse_req *req)
> > > +{
> > > +     return jiffies > req->create_time + fc->timeout.req_timeout;
> > > +}
> >
> > With jiffies we need to use time_after() and such, so we'd deal
> > with jiffies wrap-around.
> 
> Ohh I see, I guess this is because on 32-bit systems unsigned longs
> are 4 bytes?

Correct, IIRC on 32bit system jiffies wraparound every 47 or 49 days.
But I also recall that jiffies (at least in the past) were initialized
to -5 minutes so that they would wraparound during first 5 minutes
of uptime to reveal bugs.  I don't know if it's still the case though.