mm: memcontrol: rein in the CONFIG space madness

What CONFIG_INET and CONFIG_LEGACY_KMEM guard inside the memory
controller code is insignificant, having these conditionals is not
worth the complication and fragility that comes with them.

[akpm@linux-foundation.org: rework mem_cgroup_css_free() statement ordering]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 2bb14d021cd0b8aede62c701f1cd6137592ce289..47995b49942935056d0a08269aa150679ad5b04d 100644 (file)
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -233,9 +233,11 @@ struct mem_cgroup {
         */
        struct mem_cgroup_stat_cpu __percpu *stat;
 
         */
        struct mem_cgroup_stat_cpu __percpu *stat;
 

-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)
+       unsigned long           socket_pressure;
+
+       /* Legacy tcp memory accounting */

        struct cg_proto tcp_mem;
        struct cg_proto tcp_mem;

-#endif
+

 #ifndef CONFIG_SLOB
         /* Index in the kmem_cache->memcg_params.memcg_caches array */
        int kmemcg_id;
 #ifndef CONFIG_SLOB
         /* Index in the kmem_cache->memcg_params.memcg_caches array */
        int kmemcg_id;


@@ -254,10 +256,6 @@ struct mem_cgroup {
        struct wb_domain cgwb_domain;
 #endif
 
        struct wb_domain cgwb_domain;
 #endif
 

-#ifdef CONFIG_INET
-       unsigned long           socket_pressure;
-#endif
-

        /* List of events which userspace want to receive */
        struct list_head event_list;
        spinlock_t event_list_lock;
        /* List of events which userspace want to receive */
        struct list_head event_list;
        spinlock_t event_list_lock;


@@ -712,15 +710,13 @@ void sock_update_memcg(struct sock *sk);
 void sock_release_memcg(struct sock *sk);
 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 void sock_release_memcg(struct sock *sk);
 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);

-#if defined(CONFIG_MEMCG) && defined(CONFIG_INET)
+#ifdef CONFIG_MEMCG

 extern struct static_key_false memcg_sockets_enabled_key;
 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 {
 extern struct static_key_false memcg_sockets_enabled_key;
 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 {

-#ifdef CONFIG_MEMCG_LEGACY_KMEM

        if (memcg->tcp_mem.memory_pressure)
                return true;
        if (memcg->tcp_mem.memory_pressure)
                return true;

-#endif

        do {
                if (time_before(jiffies, memcg->socket_pressure))
                        return true;
        do {
                if (time_before(jiffies, memcg->socket_pressure))
                        return true;

diff --git a/init/Kconfig b/init/Kconfig
index a0a15cec8dafe87577f3b82c0c2f07183d5cefe6..22320804fbafdc57b7228b68392199657a7c2f49 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -964,20 +964,6 @@ config MEMCG_SWAP_ENABLED
          For those who want to have the feature enabled by default should
          select this option (if, for some reason, they need to disable it
          then swapaccount=0 does the trick).
          For those who want to have the feature enabled by default should
          select this option (if, for some reason, they need to disable it
          then swapaccount=0 does the trick).

-config MEMCG_LEGACY_KMEM
-       bool
-config MEMCG_KMEM
-       bool "Legacy Memory Resource Controller Kernel Memory accounting"
-       depends on MEMCG
-       depends on SLUB || SLAB
-       select MEMCG_LEGACY_KMEM
-       help
-         The Kernel Memory extension for Memory Resource Controller can limit
-         the amount of memory used by kernel objects in the system. Those are
-         fundamentally different from the entities handled by the standard
-         Memory Controller, which are page-based, and can be swapped. Users of
-         the kmem extension can use it to guarantee that no group of processes
-         will ever exhaust kernel resources alone.

 
 config BLK_CGROUP
        bool "IO controller"
 
 config BLK_CGROUP
        bool "IO controller"


@@ -1190,10 +1176,9 @@ config USER_NS
          to provide different user info for different servers.
 
          When user namespaces are enabled in the kernel it is
          to provide different user info for different servers.
 
          When user namespaces are enabled in the kernel it is

-         recommended that the MEMCG and MEMCG_KMEM options also be
-         enabled and that user-space use the memory control groups to
-         limit the amount of memory a memory unprivileged users can
-         use.
+         recommended that the MEMCG option also be enabled and that
+         user-space use the memory control groups to limit the amount
+         of memory a memory unprivileged users can use.

 
          If unsure, say N.
 
 
          If unsure, say N.
 

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 15896708429bcee1b9ee7931b1c5d5962e0e78a8..379f9911b87b7c903b99570275dda46e1b25cdde 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2842,11 +2842,9 @@ static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css,
        case _KMEM:
                counter = &memcg->kmem;
                break;
        case _KMEM:
                counter = &memcg->kmem;
                break;

-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)

        case _TCP:
                counter = &memcg->tcp_mem.memory_allocated;
                break;
        case _TCP:
                counter = &memcg->tcp_mem.memory_allocated;
                break;

-#endif

        default:
                BUG();
        }
        default:
                BUG();
        }


@@ -3006,7 +3004,6 @@ static void memcg_free_kmem(struct mem_cgroup *memcg)
 }
 #endif /* !CONFIG_SLOB */
 
 }
 #endif /* !CONFIG_SLOB */
 

-#ifdef CONFIG_MEMCG_LEGACY_KMEM

 static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
                                   unsigned long limit)
 {
 static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
                                   unsigned long limit)
 {


@@ -3024,16 +3021,7 @@ out:
        mutex_unlock(&memcg_limit_mutex);
        return ret;
 }
        mutex_unlock(&memcg_limit_mutex);
        return ret;
 }

-#else
-static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
-                                  unsigned long limit)
-{
-       return -EINVAL;
-}
-#endif /* CONFIG_MEMCG_LEGACY_KMEM */

 
 

-
-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)

 static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit)
 {
        int ret;
 static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit)
 {
        int ret;


@@ -3068,12 +3056,6 @@ out:
        mutex_unlock(&memcg_limit_mutex);
        return ret;
 }
        mutex_unlock(&memcg_limit_mutex);
        return ret;
 }

-#else
-static int memcg_update_tcp_limit(struct mem_cgroup *memcg, unsigned long limit)
-{
-       return -EINVAL;
-}
-#endif /* CONFIG_MEMCG_LEGACY_KMEM && CONFIG_INET */

 
 /*
  * The user of this function is...
 
 /*
  * The user of this function is...


@@ -3136,11 +3118,9 @@ static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf,
        case _KMEM:
                counter = &memcg->kmem;
                break;
        case _KMEM:
                counter = &memcg->kmem;
                break;

-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)

        case _TCP:
                counter = &memcg->tcp_mem.memory_allocated;
                break;
        case _TCP:
                counter = &memcg->tcp_mem.memory_allocated;
                break;

-#endif

        default:
                BUG();
        }
        default:
                BUG();
        }


@@ -4094,7 +4074,6 @@ static struct cftype mem_cgroup_legacy_files[] = {
                .seq_show = memcg_numa_stat_show,
        },
 #endif
                .seq_show = memcg_numa_stat_show,
        },
 #endif

-#ifdef CONFIG_MEMCG_LEGACY_KMEM

        {
                .name = "kmem.limit_in_bytes",
                .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
        {
                .name = "kmem.limit_in_bytes",
                .private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),


@@ -4127,7 +4106,6 @@ static struct cftype mem_cgroup_legacy_files[] = {
                .seq_show = memcg_slab_show,
        },
 #endif
                .seq_show = memcg_slab_show,
        },
 #endif

-#ifdef CONFIG_INET

        {
                .name = "kmem.tcp.limit_in_bytes",
                .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT),
        {
                .name = "kmem.tcp.limit_in_bytes",
                .private = MEMFILE_PRIVATE(_TCP, RES_LIMIT),


@@ -4151,8 +4129,6 @@ static struct cftype mem_cgroup_legacy_files[] = {
                .write = mem_cgroup_reset,
                .read_u64 = mem_cgroup_read_u64,
        },
                .write = mem_cgroup_reset,
                .read_u64 = mem_cgroup_read_u64,
        },

-#endif
-#endif

        { },    /* terminate */
 };
 
        { },    /* terminate */
 };
 


@@ -4280,14 +4256,12 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
        vmpressure_init(&memcg->vmpressure);
        INIT_LIST_HEAD(&memcg->event_list);
        spin_lock_init(&memcg->event_list_lock);
        vmpressure_init(&memcg->vmpressure);
        INIT_LIST_HEAD(&memcg->event_list);
        spin_lock_init(&memcg->event_list_lock);

+       memcg->socket_pressure = jiffies;

 #ifndef CONFIG_SLOB
        memcg->kmemcg_id = -1;
 #endif
 #ifdef CONFIG_CGROUP_WRITEBACK
        INIT_LIST_HEAD(&memcg->cgwb_list);
 #ifndef CONFIG_SLOB
        memcg->kmemcg_id = -1;
 #endif
 #ifdef CONFIG_CGROUP_WRITEBACK
        INIT_LIST_HEAD(&memcg->cgwb_list);

-#endif
-#ifdef CONFIG_INET
-       memcg->socket_pressure = jiffies;

 #endif
        return &memcg->css;
 
 #endif
        return &memcg->css;
 


@@ -4321,10 +4295,8 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css)
                memcg->soft_limit = PAGE_COUNTER_MAX;
                page_counter_init(&memcg->memsw, &parent->memsw);
                page_counter_init(&memcg->kmem, &parent->kmem);
                memcg->soft_limit = PAGE_COUNTER_MAX;
                page_counter_init(&memcg->memsw, &parent->memsw);
                page_counter_init(&memcg->kmem, &parent->kmem);

-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)

                page_counter_init(&memcg->tcp_mem.memory_allocated,
                                  &parent->tcp_mem.memory_allocated);
                page_counter_init(&memcg->tcp_mem.memory_allocated,
                                  &parent->tcp_mem.memory_allocated);

-#endif

 
                /*
                 * No need to take a reference to the parent because cgroup
 
                /*
                 * No need to take a reference to the parent because cgroup


@@ -4336,9 +4308,7 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css)
                memcg->soft_limit = PAGE_COUNTER_MAX;
                page_counter_init(&memcg->memsw, NULL);
                page_counter_init(&memcg->kmem, NULL);
                memcg->soft_limit = PAGE_COUNTER_MAX;
                page_counter_init(&memcg->memsw, NULL);
                page_counter_init(&memcg->kmem, NULL);

-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)

                page_counter_init(&memcg->tcp_mem.memory_allocated, NULL);
                page_counter_init(&memcg->tcp_mem.memory_allocated, NULL);

-#endif

                /*
                 * Deeper hierachy with use_hierarchy == false doesn't make
                 * much sense so let cgroup subsystem know about this
                /*
                 * Deeper hierachy with use_hierarchy == false doesn't make
                 * much sense so let cgroup subsystem know about this


@@ -4353,10 +4323,8 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css)
        if (ret)
                return ret;
 
        if (ret)
                return ret;
 

-#ifdef CONFIG_INET

        if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
                static_branch_inc(&memcg_sockets_enabled_key);
        if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
                static_branch_inc(&memcg_sockets_enabled_key);

-#endif

 
        /*
         * Make sure the memcg is initialized: mem_cgroup_iter()
 
        /*
         * Make sure the memcg is initialized: mem_cgroup_iter()


@@ -4403,18 +4371,13 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
 {
        struct mem_cgroup *memcg = mem_cgroup_from_css(css);
 
 {
        struct mem_cgroup *memcg = mem_cgroup_from_css(css);
 

-#ifdef CONFIG_INET

        if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
                static_branch_dec(&memcg_sockets_enabled_key);
        if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
                static_branch_dec(&memcg_sockets_enabled_key);

-#endif
-
-       memcg_free_kmem(memcg);

 
 

-#if defined(CONFIG_MEMCG_LEGACY_KMEM) && defined(CONFIG_INET)

        if (memcg->tcp_mem.active)
                static_branch_dec(&memcg_sockets_enabled_key);
        if (memcg->tcp_mem.active)
                static_branch_dec(&memcg_sockets_enabled_key);

-#endif

 
 

+       memcg_free_kmem(memcg);

        __mem_cgroup_free(memcg);
 }
 
        __mem_cgroup_free(memcg);
 }
 


@@ -5613,8 +5576,6 @@ void mem_cgroup_replace_page(struct page *oldpage, struct page *newpage)
        commit_charge(newpage, memcg, true);
 }
 
        commit_charge(newpage, memcg, true);
 }
 

-#ifdef CONFIG_INET
-

 DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
 EXPORT_SYMBOL(memcg_sockets_enabled_key);
 
 DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);
 EXPORT_SYMBOL(memcg_sockets_enabled_key);
 


@@ -5640,10 +5601,8 @@ void sock_update_memcg(struct sock *sk)
        memcg = mem_cgroup_from_task(current);
        if (memcg == root_mem_cgroup)
                goto out;
        memcg = mem_cgroup_from_task(current);
        if (memcg == root_mem_cgroup)
                goto out;

-#ifdef CONFIG_MEMCG_LEGACY_KMEM

        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcp_mem.active)
                goto out;
        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && !memcg->tcp_mem.active)
                goto out;

-#endif

        if (css_tryget_online(&memcg->css))
                sk->sk_memcg = memcg;
 out:
        if (css_tryget_online(&memcg->css))
                sk->sk_memcg = memcg;
 out:


@@ -5669,7 +5628,6 @@ bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
 {
        gfp_t gfp_mask = GFP_KERNEL;
 
 {
        gfp_t gfp_mask = GFP_KERNEL;
 

-#ifdef CONFIG_MEMCG_LEGACY_KMEM

        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
                struct page_counter *counter;
 
        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
                struct page_counter *counter;
 


@@ -5682,7 +5640,7 @@ bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
                memcg->tcp_mem.memory_pressure = 1;
                return false;
        }
                memcg->tcp_mem.memory_pressure = 1;
                return false;
        }

-#endif
+

        /* Don't block in the packet receive path */
        if (in_softirq())
                gfp_mask = GFP_NOWAIT;
        /* Don't block in the packet receive path */
        if (in_softirq())
                gfp_mask = GFP_NOWAIT;


@@ -5701,19 +5659,16 @@ bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
  */
 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
 {
  */
 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages)
 {

-#ifdef CONFIG_MEMCG_LEGACY_KMEM

        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
                page_counter_uncharge(&memcg->tcp_mem.memory_allocated,
                                      nr_pages);
                return;
        }
        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) {
                page_counter_uncharge(&memcg->tcp_mem.memory_allocated,
                                      nr_pages);
                return;
        }

-#endif
+

        page_counter_uncharge(&memcg->memory, nr_pages);
        css_put_many(&memcg->css, nr_pages);
 }
 
        page_counter_uncharge(&memcg->memory, nr_pages);
        css_put_many(&memcg->css, nr_pages);
 }
 

-#endif /* CONFIG_INET */
-

 static int __init cgroup_memory(char *s)
 {
        char *token;
 static int __init cgroup_memory(char *s)
 {
        char *token;

diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index 89b1d441af4b5bf6ac8fd3651184dedb26ac0a86..9a6c0704211c856c300f67057fc202e25c9657ab 100644 (file)
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -275,7 +275,6 @@ void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, bool tree,
 
                level = vmpressure_calc_level(scanned, reclaimed);
 
 
                level = vmpressure_calc_level(scanned, reclaimed);
 

-#ifdef CONFIG_INET

                if (level > VMPRESSURE_LOW) {
                        /*
                         * Let the socket buffer allocator know that
                if (level > VMPRESSURE_LOW) {
                        /*
                         * Let the socket buffer allocator know that


@@ -287,7 +286,6 @@ void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, bool tree,
                         */
                        memcg->socket_pressure = jiffies + HZ;
                }
                         */
                        memcg->socket_pressure = jiffies + HZ;
                }

-#endif

        }
 }
 
        }
 }