Re: [RFC PATCH v1.9 13/14] livepatch: add /proc/<pid>/patch_status

[Josh Poimboeuf]

On Thu, Mar 31, 2016 at 11:33:46AM +0200, Jiri Slaby wrote:
> On 03/25/2016, 08:35 PM, Josh Poimboeuf wrote:
> > Expose the per-task klp_universe value so users can determine which
> > tasks are holding up completion of a patching operation.
> > 
> > Call it "patch_status" rather than "universe": it's at least more
> > descriptive for the average user.
> > 
> > Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> > ---
> >  fs/proc/base.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/fs/proc/base.c b/fs/proc/base.c
> > index b1755b2..f90998b 100644
> > --- a/fs/proc/base.c
> > +++ b/fs/proc/base.c
> > @@ -2801,6 +2801,15 @@ static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
> >  	return err;
> >  }
> >  
> > +#ifdef CONFIG_LIVEPATCH
> > +static int proc_pid_patch_status(struct seq_file *m, struct pid_namespace *ns,
> > +				 struct pid *pid, struct task_struct *task)
> > +{
> > +	seq_printf(m, "%d\n", task->klp_universe);
> > +	return 0;
> > +}
> > +#endif /* CONFIG_LIVEPATCH */
> > +
> >  /*
> >   * Thread groups
> >   */
> > @@ -2900,6 +2909,9 @@ static const struct pid_entry tgid_base_stuff[] = {
> >  	REG("timers",	  S_IRUGO, proc_timers_operations),
> >  #endif
> >  	REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
> > +#ifdef CONFIG_LIVEPATCH
> > +	ONE("patch_status",  S_IRUSR, proc_pid_patch_status),
> > +#endif
> 
> I think we want to know the state about all tasks, not only group
> leaders. This should go to tid_base_stuff.

Good catch, thanks!

-- 
Josh