The patch titled Subject: memcg/hugetlb: remove memcg hugetlb try-commit-cancel protocol has been added to the -mm mm-unstable branch. Its filename is memcg-hugetlb-remove-memcg-hugetlb-try-commit-cancel-protocol.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/memcg-hugetlb-remove-memcg-hugetlb-try-commit-cancel-protocol.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Joshua Hahn <joshua.hahnjy@xxxxxxxxx> Subject: memcg/hugetlb: remove memcg hugetlb try-commit-cancel protocol Date: Wed, 11 Dec 2024 12:39:51 -0800 This patch fully removes the mem_cgroup_{try, commit, cancel}_charge functions, as well as their hugetlb variants. Link: https://lkml.kernel.org/r/20241211203951.764733-4-joshua.hahnjy@xxxxxxxxx Signed-off-by: Joshua Hahn <joshua.hahnjy@xxxxxxxxx> Acked-by: Shakeel Butt <shakeel.butt@xxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Muchun Song <muchun.song@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/memcontrol.h | 22 ----------- mm/memcontrol.c | 65 +---------------------------------- 2 files changed, 3 insertions(+), 84 deletions(-) --- a/include/linux/memcontrol.h~memcg-hugetlb-remove-memcg-hugetlb-try-commit-cancel-protocol +++ a/include/linux/memcontrol.h @@ -620,8 +620,6 @@ static inline bool mem_cgroup_below_min( page_counter_read(&memcg->memory); } -void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg); - int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp); /** @@ -646,9 +644,6 @@ static inline int mem_cgroup_charge(stru return __mem_cgroup_charge(folio, mm, gfp); } -int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, gfp_t gfp, - long nr_pages); - int mem_cgroup_charge_hugetlb(struct folio* folio, gfp_t gfp); int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm, @@ -679,7 +674,6 @@ static inline void mem_cgroup_uncharge_f __mem_cgroup_uncharge_folios(folios); } -void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages); void mem_cgroup_replace_folio(struct folio *old, struct folio *new); void mem_cgroup_migrate(struct folio *old, struct folio *new); @@ -1154,23 +1148,12 @@ static inline bool mem_cgroup_below_min( return false; } -static inline void mem_cgroup_commit_charge(struct folio *folio, - struct mem_cgroup *memcg) -{ -} - static inline int mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp) { return 0; } -static inline int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, - gfp_t gfp, long nr_pages) -{ - return 0; -} - static inline int mem_cgroup_charge_hugetlb(struct folio* folio, gfp_t gfp) { return 0; @@ -1194,11 +1177,6 @@ static inline void mem_cgroup_uncharge_f { } -static inline void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, - unsigned int nr_pages) -{ -} - static inline void mem_cgroup_replace_folio(struct folio *old, struct folio *new) { --- a/mm/memcontrol.c~memcg-hugetlb-remove-memcg-hugetlb-try-commit-cancel-protocol +++ a/mm/memcontrol.c @@ -2383,21 +2383,6 @@ done_restock: return 0; } -/** - * mem_cgroup_cancel_charge() - cancel an uncommitted try_charge() call. - * @memcg: memcg previously charged. - * @nr_pages: number of pages previously charged. - */ -void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) -{ - 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); -} - static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) { VM_BUG_ON_FOLIO(folio_memcg_charged(folio), folio); @@ -2411,18 +2396,6 @@ static void commit_charge(struct folio * folio->memcg_data = (unsigned long)memcg; } -/** - * mem_cgroup_commit_charge - commit a previously successful try_charge(). - * @folio: folio to commit the charge to. - * @memcg: memcg previously charged. - */ -void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg) -{ - css_get(&memcg->css); - commit_charge(folio, memcg); - memcg1_commit_charge(folio, memcg); -} - static inline void __mod_objcg_mlstate(struct obj_cgroup *objcg, struct pglist_data *pgdat, enum node_stat_item idx, int nr) @@ -4510,7 +4483,9 @@ static int charge_memcg(struct folio *fo if (ret) goto out; - mem_cgroup_commit_charge(folio, memcg); + css_get(&memcg->css); + commit_charge(folio, memcg); + memcg1_commit_charge(folio, memcg); out: return ret; } @@ -4528,40 +4503,6 @@ int __mem_cgroup_charge(struct folio *fo } /** - * mem_cgroup_hugetlb_try_charge - try to charge the memcg for a hugetlb folio - * @memcg: memcg to charge. - * @gfp: reclaim mode. - * @nr_pages: number of pages to charge. - * - * This function is called when allocating a huge page folio to determine if - * the memcg has the capacity for it. It does not commit the charge yet, - * as the hugetlb folio itself has not been obtained from the hugetlb pool. - * - * Once we have obtained the hugetlb folio, we can call - * mem_cgroup_commit_charge() to commit the charge. If we fail to obtain the - * folio, we should instead call mem_cgroup_cancel_charge() to undo the effect - * of try_charge(). - * - * Returns 0 on success. Otherwise, an error code is returned. - */ -int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, gfp_t gfp, - long nr_pages) -{ - /* - * If hugetlb memcg charging is not enabled, do not fail hugetlb allocation, - * but do not attempt to commit charge later (or cancel on error) either. - */ - if (mem_cgroup_disabled() || !memcg || - !cgroup_subsys_on_dfl(memory_cgrp_subsys) || !memcg_accounts_hugetlb()) - return -EOPNOTSUPP; - - if (try_charge(memcg, gfp, nr_pages)) - return -ENOMEM; - - return 0; -} - -/** * mem_cgroup_charge_hugetlb - charge the memcg for a hugetlb folio * @folio: folio being charged * @gfp: reclaim mode _ Patches currently in -mm which might be from joshua.hahnjy@xxxxxxxxx are memcg-hugetlb-introduce-memcg_accounts_hugetlb.patch memcg-hugetlb-introduce-mem_cgroup_charge_hugetlb.patch memcg-hugetlb-remove-memcg-hugetlb-try-commit-cancel-protocol.patch