On Friday, September 23, 2016 4:32 PM, Michal Hocko wrote
> On Fri 23-09-16 16:29:36, Hillf Danton wrote:
> [...]
> > > @@ -3659,6 +3661,15 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned
> > > int order,
> > > else
> > > no_progress_loops++;
> > >
> > > + /* Make sure we know about allocations which stall for too long */
> > > + if (!(gfp_mask & __GFP_NOWARN) && time_after(jiffies, alloc_start +
> > > stall_timeout)) {
> > > + pr_warn("%s: page alloction stalls for %ums: order:%u
> > > mode:%#x(%pGg)\n",
> > > + current->comm,
> > > jiffies_to_msecs(jiffies-alloc_start),
> >
> > Better if pid is also printed.
>
> I've tried to be consistent with warn_alloc_failed and that doesn't
> print pid either. Maybe both of them should. Dunno
>
With pid imho we can distinguish two tasks with same name in a simpler way.
> > > + order, gfp_mask, &gfp_mask);
> > > + stall_timeout += 10 * HZ;
> >
> > Alternatively alloc_start = jiffies;
>
> Then we would lose the cumulative time in the output which is imho
> helpful because you cannot tell whether the new warning is a new request
> or the old one still looping.
>
Fair.
thanks
Hillf
