Re: [RFC] proc, coredump: add CoreDumping flag to /proc/pid/status

[Roman Gushchin]

On Thu, Sep 14, 2017 at 01:46:43AM +0300, Alexey Dobriyan wrote:
> On Wed, Sep 13, 2017 at 03:21:59PM -0700, Roman Gushchin wrote:
> > On Thu, Sep 14, 2017 at 01:15:26AM +0300, Alexey Dobriyan wrote:
> > > > To provide an ability to detect if a process is in the state of
> > > > being coreduped, we can expose a boolean CoreDumping flag
> > > > in /proc/pid/status.
> > > 
> > > Or add "State: C" ?
> > 
> > A program in such state can also sleep and run, so it's not
> > a state in terms of process states.
> 
> Well, maybe something will break from seeing unknown process state.
> 
> Regardless, symlink /proc/$PID/coredump pointing to either "0" or "1"
> is faster than open+read+parse+close.

Performance doesn't really matter in this case: nobody should check
this flag often. An expected usecase is described above: check the flag
once before killing the process by timeout.
So, it doesn't look deserving a separate entity in procfs.