The patch titled Subject: mm: memcg: put cgroup v1-related members of task_struct under config option has been added to the -mm mm-unstable branch. Its filename is mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option.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: Roman Gushchin <roman.gushchin@xxxxxxxxx> Subject: mm: memcg: put cgroup v1-related members of task_struct under config option Date: Mon, 24 Jun 2024 17:59:05 -0700 Guard cgroup v1-related members of task_struct under the CONFIG_MEMCG_V1 config option, so that users who adopted cgroup v2 don't have to waste the memory for fields which are never accessed. Link: https://lkml.kernel.org/r/20240625005906.106920-14-roman.gushchin@xxxxxxxxx Signed-off-by: Roman Gushchin <roman.gushchin@xxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Shakeel Butt <shakeel.butt@xxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Muchun Song <muchun.song@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/memcontrol.h | 6 +++--- init/Kconfig | 9 +++++++++ mm/Makefile | 3 ++- mm/memcontrol-v1.h | 21 ++++++++++++++++++++- mm/memcontrol.c | 10 +++++++--- 5 files changed, 41 insertions(+), 8 deletions(-) --- a/include/linux/memcontrol.h~mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option +++ a/include/linux/memcontrol.h @@ -1851,7 +1851,7 @@ static inline bool mem_cgroup_zswap_writ /* Cgroup v1-related declarations */ -#ifdef CONFIG_MEMCG +#ifdef CONFIG_MEMCG_V1 unsigned long memcg1_soft_limit_reclaim(pg_data_t *pgdat, int order, gfp_t gfp_mask, unsigned long *total_scanned); @@ -1883,7 +1883,7 @@ static inline void mem_cgroup_unlock_pag rcu_read_unlock(); } -#else /* CONFIG_MEMCG */ +#else /* CONFIG_MEMCG_V1 */ static inline unsigned long memcg1_soft_limit_reclaim(pg_data_t *pgdat, int order, gfp_t gfp_mask, @@ -1922,6 +1922,6 @@ static inline bool mem_cgroup_oom_synchr return false; } -#endif /* CONFIG_MEMCG */ +#endif /* CONFIG_MEMCG_V1 */ #endif /* _LINUX_MEMCONTROL_H */ --- a/init/Kconfig~mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option +++ a/init/Kconfig @@ -969,6 +969,15 @@ config MEMCG help Provides control over the memory footprint of tasks in a cgroup. +config MEMCG_V1 + bool "Legacy memory controller" + depends on MEMCG + default n + help + Legacy cgroup v1 memory controller. + + San N is unsure. + config MEMCG_KMEM bool depends on MEMCG --- a/mm/Makefile~mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option +++ a/mm/Makefile @@ -96,7 +96,8 @@ obj-$(CONFIG_NUMA) += memory-tiers.o obj-$(CONFIG_DEVICE_MIGRATION) += migrate_device.o obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += huge_memory.o khugepaged.o obj-$(CONFIG_PAGE_COUNTER) += page_counter.o -obj-$(CONFIG_MEMCG) += memcontrol.o memcontrol-v1.o vmpressure.o +obj-$(CONFIG_MEMCG_V1) += memcontrol-v1.o +obj-$(CONFIG_MEMCG) += memcontrol.o vmpressure.o ifdef CONFIG_SWAP obj-$(CONFIG_MEMCG) += swap_cgroup.o endif --- a/mm/memcontrol.c~mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option +++ a/mm/memcontrol.c @@ -4436,18 +4436,20 @@ struct cgroup_subsys memory_cgrp_subsys .css_free = mem_cgroup_css_free, .css_reset = mem_cgroup_css_reset, .css_rstat_flush = mem_cgroup_css_rstat_flush, - .can_attach = memcg1_can_attach, #if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM) .attach = mem_cgroup_attach, #endif - .cancel_attach = memcg1_cancel_attach, - .post_attach = memcg1_move_task, #ifdef CONFIG_MEMCG_KMEM .fork = mem_cgroup_fork, .exit = mem_cgroup_exit, #endif .dfl_cftypes = memory_files, +#ifdef CONFIG_MEMCG_V1 + .can_attach = memcg1_can_attach, + .cancel_attach = memcg1_cancel_attach, + .post_attach = memcg1_move_task, .legacy_cftypes = mem_cgroup_legacy_files, +#endif .early_init = 0, }; @@ -5618,7 +5620,9 @@ static int __init mem_cgroup_swap_init(v return 0; WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files)); +#ifdef CONFIG_MEMCG_V1 WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files)); +#endif #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files)); #endif --- a/mm/memcontrol-v1.h~mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option +++ a/mm/memcontrol-v1.h @@ -75,7 +75,7 @@ unsigned long memcg_page_state_local_out int memory_stat_show(struct seq_file *m, void *v); /* Cgroup v1-specific declarations */ - +#ifdef CONFIG_MEMCG_V1 void memcg1_remove_from_trees(struct mem_cgroup *memcg); static inline void memcg1_soft_limit_reset(struct mem_cgroup *memcg) @@ -110,4 +110,23 @@ void memcg1_stat_format(struct mem_cgrou extern struct cftype memsw_files[]; extern struct cftype mem_cgroup_legacy_files[]; +#else /* CONFIG_MEMCG_V1 */ + +static inline void memcg1_remove_from_trees(struct mem_cgroup *memcg) {} +static inline void memcg1_soft_limit_reset(struct mem_cgroup *memcg) {} +static inline bool memcg1_wait_acct_move(struct mem_cgroup *memcg) { return false; } +static inline void memcg1_css_offline(struct mem_cgroup *memcg) {} + +static inline bool memcg1_oom_prepare(struct mem_cgroup *memcg, bool *locked) { return true; } +static inline void memcg1_oom_finish(struct mem_cgroup *memcg, bool locked) {} +static inline void memcg1_oom_recover(struct mem_cgroup *memcg) {} + +static inline void memcg1_check_events(struct mem_cgroup *memcg, int nid) {} + +static inline void memcg1_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) {} + +extern struct cftype memsw_files[]; +extern struct cftype mem_cgroup_legacy_files[]; +#endif /* CONFIG_MEMCG_V1 */ + #endif /* __MM_MEMCONTROL_V1_H */ _ Patches currently in -mm which might be from roman.gushchin@xxxxxxxxx are mm-memcg-introduce-memcontrol-v1c.patch mm-memcg-move-soft-limit-reclaim-code-to-memcontrol-v1c.patch mm-memcg-rename-soft-limit-reclaim-related-functions.patch mm-memcg-move-charge-migration-code-to-memcontrol-v1c.patch mm-memcg-rename-charge-move-related-functions.patch mm-memcg-move-legacy-memcg-event-code-into-memcontrol-v1c.patch mm-memcg-rename-memcg_check_events.patch mm-memcg-move-cgroup-v1-oom-handling-code-into-memcontrol-v1c.patch mm-memcg-rename-memcg_oom_recover.patch mm-memcg-move-cgroup-v1-interface-files-to-memcontrol-v1c.patch mm-memcg-make-memcg1_update_tree-static.patch mm-memcg-group-cgroup-v1-memcg-related-declarations.patch mm-memcg-put-cgroup-v1-related-members-of-task_struct-under-config-option.patch maintainers-add-mm-memcontrol-v1c-h-to-the-list-of-maintained-files.patch