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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 7C557A0006 X-Stat-Signature: 3d686rp4iwn46cif5fnkamk3qz1ezfo5 X-HE-Tag: 1675414738-697787 X-HE-Meta: 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 L9YsKqWv ed51TqOTy2S0EFF1R4EXmG1wnjSJ4MXq+9VZVVAh1EZNAOm2KxzlyyoWeFOsPMAARySSUHvuV8+el65R8SKUi0kLAMIgEG5HVt0q6trXcu9k1ZOpHLprGjHLYcqlcTn9u01VjGa096DiYOyWaxdsDPBp+qDNkxmP0m11sl9R3bFtWBW/EUOLmFuF4VEC2B1fP1gX7SOU7gkYpJ5zEULEjhuLFeuWbtEGv7KHbfGSsIPS39zbFRcYxmtRLwEFdDCG+PL+ljtVdbcKGP8YgHBojgNNkww2g/B31olVzL9UA0eVu+G5FsIvCL1+cpiBQV0qS7xNxrev76fki2Rc= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu 02-02-23 10:24:08, Shakeel Butt wrote: > On Thu, Feb 2, 2023 at 12:27 AM Michal Hocko wrote: > > > > On Thu 02-02-23 12:32:57, zhaoyang.huang wrote: > > > From: Zhaoyang Huang > > > > > > Introducing memory.root_current for the memory charges on root_mem_cgroup. > > > > Charges are not currently accounted for the root memcg universally. See > > try_charge which is used for all user space and skmem charges. I am not > > 100% sure about objcg based accounting because there is no explicit > > check for the root memcg but this might be hidden somewhere as well. > > Yes in __get_obj_cgroup_from_memcg(). However the reason to use > try_charge_memcg() to bypass root check was to avoid the race with > reparenting. More details in c5c8b16b596e ("mm: memcontrol: fix > root_mem_cgroup charging"). Thanks for the pointer! > > That means that the patch as is doesn't really provide and usable value. > > The root exemption has been removed in the past but that has been > > reverted due to a regression. See ce00a967377b ("mm: memcontrol: revert > > use of root_mem_cgroup res_counter") for more. > > > > One advantage I can see is if someone is looking for usage for all top > containers (alive or zombie) but I wanted to know if that was the real > motivation behind the patch. Isn't that just a global stats that we already display via /proc files? -- Michal Hocko SUSE Labs