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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 00E27211BA X-Spam-Score: -4.51 X-Rspamd-Action: no action X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; RCPT_COUNT_SEVEN(0.00)[11]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; MIME_TRACE(0.00)[0:+]; FUZZY_BLOCKED(0.00)[rspamd.com]; RCVD_TLS_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,suse.cz:dkim,suse.cz:mid,suse.cz:email]; DKIM_TRACE(0.00)[suse.cz:+] X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Spam-Flag: NO X-Spam-Level: On 3/15/25 18:49, Shakeel Butt wrote: > refill_stock can not be called with root memcg, so there is no need to > check it. > > Signed-off-by: Shakeel Butt Acked-by: Vlastimil Babka It's not trivial to verify this so I'd add VM_WARN_ON_ONCE(mem_cgroup_is_root(memcg)); as Roman suggested in patch 4 reply. > --- > mm/memcontrol.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index b29433eb17fa..c09a32e93d39 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1883,6 +1883,7 @@ static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) > drain_stock(stock); > } > > +/* Should never be called with root_mem_cgroup. */ > static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) > { > unsigned long flags; > @@ -1892,8 +1893,6 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) > * In case of unlikely failure to lock percpu stock_lock > * uncharge memcg directly. > */ > - if (mem_cgroup_is_root(memcg)) > - return; > page_counter_uncharge(&memcg->memory, nr_pages); > if (do_memsw_account()) > page_counter_uncharge(&memcg->memsw, nr_pages);