Commit b6c1a8af authored by Yafang Shao's avatar Yafang Shao Committed by Alexei Starovoitov
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mm: memcontrol: add new kernel parameter cgroup.memory=nobpf 



Add new kernel parameter cgroup.memory=nobpf to allow user disable bpf
memory accounting. This is a preparation for the followup patch.

Signed-off-by: default avatarYafang Shao <laoar.shao@gmail.com>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Acked-by: default avatarRoman Gushchin <roman.gushchin@linux.dev>
Link: https://lore.kernel.org/r/20230210154734.4416-2-laoar.shao@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 7e2a9ebe

Documentation/admin-guide/kernel-parameters.txt

+1 −0
Original line number Diff line number Diff line
@@ -557,6 +557,7 @@ 
			Format: <string>

			nosocket -- Disable socket memory accounting.

			nokmem -- Disable kernel memory accounting.

			nobpf -- Disable BPF memory accounting.



	checkreqprot=	[SELINUX] Set initial checkreqprot flag value.

			Format: { "0" | "1" }

include/linux/memcontrol.h

+11 −0
Original line number Diff line number Diff line
@@ -1754,6 +1754,12 @@ struct obj_cgroup *get_obj_cgroup_from_page(struct page *page); 
int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size);

void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size);



extern struct static_key_false memcg_bpf_enabled_key;

static inline bool memcg_bpf_enabled(void)

{

	return static_branch_likely(&memcg_bpf_enabled_key);

}



extern struct static_key_false memcg_kmem_enabled_key;



static inline bool memcg_kmem_enabled(void)
@@ -1832,6 +1838,11 @@ static inline struct obj_cgroup *get_obj_cgroup_from_page(struct page *page) 
	return NULL;

}



static inline bool memcg_bpf_enabled(void)

{

	return false;

}



static inline bool memcg_kmem_enabled(void)

{

	return false;

mm/memcontrol.c

+18 −0
Original line number Diff line number Diff line
@@ -88,6 +88,9 @@ static bool cgroup_memory_nosocket __ro_after_init; 
/* Kernel memory accounting disabled? */

static bool cgroup_memory_nokmem __ro_after_init;



/* BPF memory accounting disabled? */

static bool cgroup_memory_nobpf __ro_after_init;



#ifdef CONFIG_CGROUP_WRITEBACK

static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq);

#endif
@@ -347,6 +350,9 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg, 
 */

DEFINE_STATIC_KEY_FALSE(memcg_kmem_enabled_key);

EXPORT_SYMBOL(memcg_kmem_enabled_key);



DEFINE_STATIC_KEY_FALSE(memcg_bpf_enabled_key);

EXPORT_SYMBOL(memcg_bpf_enabled_key);

#endif



/**
@@ -5357,6 +5363,11 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) 
	if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)

		static_branch_inc(&memcg_sockets_enabled_key);



#if defined(CONFIG_MEMCG_KMEM)

	if (!cgroup_memory_nobpf)

		static_branch_inc(&memcg_bpf_enabled_key);

#endif



	return &memcg->css;

}
@@ -5441,6 +5452,11 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css) 
	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_active)

		static_branch_dec(&memcg_sockets_enabled_key);



#if defined(CONFIG_MEMCG_KMEM)

	if (!cgroup_memory_nobpf)

		static_branch_dec(&memcg_bpf_enabled_key);

#endif



	vmpressure_cleanup(&memcg->vmpressure);

	cancel_work_sync(&memcg->high_work);

	mem_cgroup_remove_from_trees(memcg);
@@ -7269,6 +7285,8 @@ static int __init cgroup_memory(char *s) 
			cgroup_memory_nosocket = true;

		if (!strcmp(token, "nokmem"))

			cgroup_memory_nokmem = true;

		if (!strcmp(token, "nobpf"))

			cgroup_memory_nobpf = true;

	}

	return 1;

}