On Thu, Jul 20, 2023 at 11:24:20AM -0700, Yosry Ahmed wrote:
> On Thu, Jul 20, 2023 at 11:13 AM Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote:
> >
> > On Thu, Jul 20, 2023 at 07:08:24AM +0000, Yosry Ahmed wrote:
> > > Add a sysctl to enable/disable memory recharging for offline memcgs. Add
> > > a config option to control whether or not it is enabled by default.
> > >
> > > Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> > > ---
> > > include/linux/memcontrol.h | 2 ++
> > > kernel/sysctl.c | 11 +++++++++++
> > > mm/Kconfig | 12 ++++++++++++
> > > mm/memcontrol.c | 9 ++++++++-
> > > 4 files changed, 33 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> > > index 59b653d4a76e..ae9f09ee90cb 100644
> > > --- a/include/linux/memcontrol.h
> > > +++ b/include/linux/memcontrol.h
> > > @@ -60,6 +60,8 @@ struct mem_cgroup_reclaim_cookie {
> > >
> > > #ifdef CONFIG_MEMCG
> > >
> > > +extern int sysctl_recharge_offline_memcgs;
> > > +
> > > #define MEM_CGROUP_ID_SHIFT 16
> > > #define MEM_CGROUP_ID_MAX USHRT_MAX
> > >
> > > diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> > > index 354a2d294f52..1735d1d95652 100644
> > > --- a/kernel/sysctl.c
> > > +++ b/kernel/sysctl.c
> > > @@ -2249,6 +2249,17 @@ static struct ctl_table vm_table[] = {
> > > .extra2 = (void *)&mmap_rnd_compat_bits_max,
> > > },
> > > #endif
> > > +#ifdef CONFIG_MEMCG
> > > + {
> > > + .procname = "recharge_offline_memcgs",
> > > + .data = &sysctl_recharge_offline_memcgs,
> > > + .maxlen = sizeof(sysctl_recharge_offline_memcgs),
> > > + .mode = 0644,
> > > + .proc_handler = proc_dointvec_minmax,
> > > + .extra1 = SYSCTL_ZERO,
> > > + .extra2 = SYSCTL_ONE,
> > > + },
> > > +#endif /* CONFIG_MEMCG */
> > > { }
> > > };
> >
> > Please don't add any more sysctls to kernel/sysctl.c, git log that file
> > for a series of cleanups which show how to use your own and why we have
> > been doing that cleanup.
>
> Thanks for pointing this out, I definitely missed it. Will do that in
> the next version. I guess this will also reduce the reviewer churn if
> I won't be touching kernel/sysctl.c?
Right, it means I don't have to care anymore about random sysctl knobs.
Let people knob it all up.
Luis
