kernel: res_counter: remove the unused API

All memory accounting and limiting has been switched over to the
lockless page counters.  Bye, res_counter!

[akpm@linux-foundation.org: update Documentation/cgroups/memory.txt]
[mhocko@suse.cz: ditch the last remainings of res_counter]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 0 insertions, 212 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 17ea6d4a9a24..a59481a3fa6c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -57,7 +57,6 @@ obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_PID_NS) += pid_namespace.o
 obj-$(CONFIG_IKCONFIG) += configs.o
-obj-$(CONFIG_RESOURCE_COUNTERS) += res_counter.o
 obj-$(CONFIG_SMP) += stop_machine.o
 obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
 obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
deleted file mode 100644
index e791130f85a7..000000000000
--- a/kernel/res_counter.c
+++ /dev/null
@@ -1,211 +0,0 @@
-/*
- * resource cgroups
- *
- * Copyright 2007 OpenVZ SWsoft Inc
- *
- * Author: Pavel Emelianov <xemul@openvz.org>
- *
- */
-
-#include <linux/types.h>
-#include <linux/parser.h>
-#include <linux/fs.h>
-#include <linux/res_counter.h>
-#include <linux/uaccess.h>
-#include <linux/mm.h>
-
-void res_counter_init(struct res_counter *counter, struct res_counter *parent)
-{
-        spin_lock_init(&counter->lock);
-        counter->limit = RES_COUNTER_MAX;
-        counter->soft_limit = RES_COUNTER_MAX;
-        counter->parent = parent;
-}
-
-static u64 res_counter_uncharge_locked(struct res_counter *counter,
-                                       unsigned long val)
-{
-        if (WARN_ON(counter->usage < val))
-                val = counter->usage;
-
-        counter->usage -= val;
-        return counter->usage;
-}
-
-static int res_counter_charge_locked(struct res_counter *counter,
-                                     unsigned long val, bool force)
-{
-        int ret = 0;
-
-        if (counter->usage + val > counter->limit) {
-                counter->failcnt++;
-                ret = -ENOMEM;
-                if (!force)
-                        return ret;
-        }
-
-        counter->usage += val;
-        if (counter->usage > counter->max_usage)
-                counter->max_usage = counter->usage;
-        return ret;
-}
-
-static int __res_counter_charge(struct res_counter *counter, unsigned long val,
-                                struct res_counter **limit_fail_at, bool force)
-{
-        int ret, r;
-        unsigned long flags;
-        struct res_counter *c, *u;
-
-        r = ret = 0;
-        *limit_fail_at = NULL;
-        local_irq_save(flags);
-        for (c = counter; c != NULL; c = c->parent) {
-                spin_lock(&c->lock);
-                r = res_counter_charge_locked(c, val, force);
-                spin_unlock(&c->lock);
-                if (r < 0 && !ret) {
-                        ret = r;
-                        *limit_fail_at = c;
-                        if (!force)
-                                break;
-                }
-        }
-
-        if (ret < 0 && !force) {
-                for (u = counter; u != c; u = u->parent) {
-                        spin_lock(&u->lock);
-                        res_counter_uncharge_locked(u, val);
-                        spin_unlock(&u->lock);
-                }
-        }
-        local_irq_restore(flags);
-
-        return ret;
-}
-
-int res_counter_charge(struct res_counter *counter, unsigned long val,
-                        struct res_counter **limit_fail_at)
-{
-        return __res_counter_charge(counter, val, limit_fail_at, false);
-}
-
-int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
-                              struct res_counter **limit_fail_at)
-{
-        return __res_counter_charge(counter, val, limit_fail_at, true);
-}
-
-u64 res_counter_uncharge_until(struct res_counter *counter,
-                               struct res_counter *top,
-                               unsigned long val)
-{
-        unsigned long flags;
-        struct res_counter *c;
-        u64 ret = 0;
-
-        local_irq_save(flags);
-        for (c = counter; c != top; c = c->parent) {
-                u64 r;
-                spin_lock(&c->lock);
-                r = res_counter_uncharge_locked(c, val);
-                if (c == counter)
-                        ret = r;
-                spin_unlock(&c->lock);
-        }
-        local_irq_restore(flags);
-        return ret;
-}
-
-u64 res_counter_uncharge(struct res_counter *counter, unsigned long val)
-{
-        return res_counter_uncharge_until(counter, NULL, val);
-}
-
-static inline unsigned long long *
-res_counter_member(struct res_counter *counter, int member)
-{
-        switch (member) {
-        case RES_USAGE:
-                return &counter->usage;
-        case RES_MAX_USAGE:
-                return &counter->max_usage;
-        case RES_LIMIT:
-                return &counter->limit;
-        case RES_FAILCNT:
-                return &counter->failcnt;
-        case RES_SOFT_LIMIT:
-                return &counter->soft_limit;
-        };
-
-        BUG();
-        return NULL;
-}
-
-ssize_t res_counter_read(struct res_counter *counter, int member,
-                const char __user *userbuf, size_t nbytes, loff_t *pos,
-                int (*read_strategy)(unsigned long long val, char *st_buf))
-{
-        unsigned long long *val;
-        char buf[64], *s;
-
-        s = buf;
-        val = res_counter_member(counter, member);
-        if (read_strategy)
-                s += read_strategy(*val, s);
-        else
-                s += sprintf(s, "%llu\n", *val);
-        return simple_read_from_buffer((void __user *)userbuf, nbytes,
-                        pos, buf, s - buf);
-}
-
-#if BITS_PER_LONG == 32
-u64 res_counter_read_u64(struct res_counter *counter, int member)
-{
-        unsigned long flags;
-        u64 ret;
-
-        spin_lock_irqsave(&counter->lock, flags);
-        ret = *res_counter_member(counter, member);
-        spin_unlock_irqrestore(&counter->lock, flags);
-
-        return ret;
-}
-#else
-u64 res_counter_read_u64(struct res_counter *counter, int member)
-{
-        return *res_counter_member(counter, member);
-}
-#endif
-
-int res_counter_memparse_write_strategy(const char *buf,
-                                        unsigned long long *resp)
-{
-        char *end;
-        unsigned long long res;
-
-        /* return RES_COUNTER_MAX(unlimited) if "-1" is specified */
-        if (*buf == '-') {
-                int rc = kstrtoull(buf + 1, 10, &res);
-
-                if (rc)
-                        return rc;
-                if (res != 1)
-                        return -EINVAL;
-                *resp = RES_COUNTER_MAX;
-                return 0;
-        }
-
-        res = memparse(buf, &end);
-        if (*end != '\0')
-                return -EINVAL;
-
-        if (PAGE_ALIGN(res) >= res)
-                res = PAGE_ALIGN(res);
-        else
-                res = RES_COUNTER_MAX;
-
-        *resp = res;
-
-        return 0;
-}