Hi Michal, > -----Original Message----- > From: Michal Hocko <mhocko@xxxxxxxx> > Sent: Wednesday, August 21, 2024 8:11 AM > To: Sridhar, Kanchana P <kanchana.p.sridhar@xxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; > hannes@xxxxxxxxxxx; yosryahmed@xxxxxxxxxx; nphamcs@xxxxxxxxx; > ryan.roberts@xxxxxxx; Huang, Ying <ying.huang@xxxxxxxxx>; > 21cnbao@xxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx; Zou, Nanhai > <nanhai.zou@xxxxxxxxx>; Feghali, Wajdi K <wajdi.k.feghali@xxxxxxxxx>; > Gopal, Vinodh <vinodh.gopal@xxxxxxxxx> > Subject: Re: [PATCH v1] mm: Defines obj_cgroup_get() if CONFIG_MEMCG is > not defined. > > On Tue 20-08-24 12:50:05, Kanchana P Sridhar wrote: > > This resolves an issue with obj_cgroup_get() not being defined > > if CONFIG_MEMCG is not defined. > > Could you paste the compilation error and which tree this is based on? Sure, this link contains the compilation error reported by the kernel test robot: https://lore.kernel.org/oe-kbuild-all/202408202320.trSaY2o4-lkp@xxxxxxxxx/ Error: kernel test robot noticed the following build errors: [auto build test ERROR on 8c0b4f7b65fd1ca7af01267f491e815a40d77444] url: https://github.com/intel-lab-lkp/linux/commits/Kanchana-P-Sridhar/mm-zswap-zswap_is_folio_same_filled-takes-an-index-in-the-folio/20240819-101738 base: 8c0b4f7b65fd1ca7af01267f491e815a40d77444 patch link: https://lore.kernel.org/r/20240819021621.29125-3-kanchana.p.sridhar%40intel.com patch subject: [PATCH v4 2/4] mm: zswap: zswap_store() extended to handle mTHP folios. config: sparc-randconfig-002-20240820 (https://download.01.org/0day-ci/archive/20240820/202408202320.trSaY2o4-lkp@xxxxxxxxx/config) compiler: sparc-linux-gcc (GCC) 14.1.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240820/202408202320.trSaY2o4-lkp@xxxxxxxxx/reproduce) All errors (new ones prefixed by >>): mm/zswap.c: In function 'zswap_store_page': >> mm/zswap.c:1534:17: error: implicit declaration of function 'obj_cgroup_get'; did you mean 'obj_cgroup_put'? [-Wimplicit-function-declaration] 1534 | obj_cgroup_get(objcg); | ^~~~~~~~~~~~~~ | obj_cgroup_put My patch fixing the error is based on the mm-unstable branch in this git tree: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/ Please let me know if you need any other info. Thanks, Kanchana > > > This causes build errors if > > obj_cgroup_get() is called from code that is agnostic of CONFIG_MEMCG. > > > > The patch resolves this. > > > > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@xxxxxxxxx> > > --- > > include/linux/memcontrol.h | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > > index fe05fdb92779..f693d254ab2a 100644 > > --- a/include/linux/memcontrol.h > > +++ b/include/linux/memcontrol.h > > @@ -1281,6 +1281,10 @@ struct mem_cgroup > *mem_cgroup_from_css(struct cgroup_subsys_state *css) > > return NULL; > > } > > > > +static inline void obj_cgroup_get(struct obj_cgroup *objcg) > > +{ > > +} > > + > > static inline void obj_cgroup_put(struct obj_cgroup *objcg) > > { > > } > > > > base-commit: 7d0b0d4b77b368b2111fc8b4449e33dfb3c34087 > > -- > > 2.27.0 > > > > -- > Michal Hocko > SUSE Labs
