diff options
| -rw-r--r-- | Documentation/cgroups/memory.txt | 17 | ||||
| -rw-r--r-- | Documentation/cgroups/resource_counter.txt | 197 | ||||
| -rw-r--r-- | include/linux/res_counter.h | 223 | ||||
| -rw-r--r-- | init/Kconfig | 6 | ||||
| -rw-r--r-- | kernel/Makefile | 1 | ||||
| -rw-r--r-- | kernel/res_counter.c | 211 |
6 files changed, 8 insertions, 647 deletions
diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt index f624727ab404..67613ff0270c 100644 --- a/Documentation/cgroups/memory.txt +++ b/Documentation/cgroups/memory.txt @@ -116,16 +116,16 @@ The memory controller is the first controller developed. 2.1. Design -The core of the design is a counter called the res_counter. The res_counter -tracks the current memory usage and limit of the group of processes associated -with the controller. Each cgroup has a memory controller specific data -structure (mem_cgroup) associated with it. +The core of the design is a counter called the page_counter. The +page_counter tracks the current memory usage and limit of the group of +processes associated with the controller. Each cgroup has a memory controller +specific data structure (mem_cgroup) associated with it. 2.2. Accounting +--------------------+ - | mem_cgroup | - | (res_counter) | + | mem_cgroup | + | (page_counter) | +--------------------+ / ^ \ / | \ @@ -352,9 +352,8 @@ set: 0. Configuration a. Enable CONFIG_CGROUPS -b. Enable CONFIG_RESOURCE_COUNTERS -c. Enable CONFIG_MEMCG -d. Enable CONFIG_MEMCG_SWAP (to use swap extension) +b. Enable CONFIG_MEMCG +c. Enable CONFIG_MEMCG_SWAP (to use swap extension) d. Enable CONFIG_MEMCG_KMEM (to use kmem extension) 1. Prepare the cgroups (see cgroups.txt, Why are cgroups needed?) diff --git a/Documentation/cgroups/resource_counter.txt b/Documentation/cgroups/resource_counter.txt deleted file mode 100644 index 762ca54eb929..000000000000 --- a/Documentation/cgroups/resource_counter.txt +++ /dev/null @@ -1,197 +0,0 @@ - - The Resource Counter - -The resource counter, declared at include/linux/res_counter.h, -is supposed to facilitate the resource management by controllers -by providing common stuff for accounting. - -This "stuff" includes the res_counter structure and routines -to work with it. - - - -1. Crucial parts of the res_counter structure - - a. unsigned long long usage - - The usage value shows the amount of a resource that is consumed - by a group at a given time. The units of measurement should be - determined by the controller that uses this counter. E.g. it can - be bytes, items or any other unit the controller operates on. - - b. unsigned long long max_usage - - The maximal value of the usage over time. - - This value is useful when gathering statistical information about - the particular group, as it shows the actual resource requirements - for a particular group, not just some usage snapshot. - - c. unsigned long long limit - - The maximal allowed amount of resource to consume by the group. In - case the group requests for more resources, so that the usage value - would exceed the limit, the resource allocation is rejected (see - the next section). - - d. unsigned long long failcnt - - The failcnt stands for "failures counter". This is the number of - resource allocation attempts that failed. - - c. spinlock_t lock - - Protects changes of the above values. - - - -2. Basic accounting routines - - a. void res_counter_init(struct res_counter *rc, - struct res_counter *rc_parent) - - Initializes the resource counter. As usual, should be the first - routine called for a new counter. - - The struct res_counter *parent can be used to define a hierarchical - child -> parent relationship directly in the res_counter structure, - NULL can be used to define no relationship. - - c. int res_counter_charge(struct res_counter *rc, unsigned long val, - struct res_counter **limit_fail_at) - - When a resource is about to be allocated it has to be accounted - with the appropriate resource counter (controller should determine - which one to use on its own). This operation is called "charging". - - This is not very important which operation - resource allocation - or charging - is performed first, but - * if the allocation is performed first, this may create a - temporary resource over-usage by the time resource counter is - charged; - * if the charging is performed first, then it should be uncharged - on error path (if the one is called). - - If the charging fails and a hierarchical dependency exists, the - limit_fail_at parameter is set to the particular res_counter element - where the charging failed. - - d. u64 res_counter_uncharge(struct res_counter *rc, unsigned long val) - - When a resource is released (freed) it should be de-accounted - from the resource counter it was accounted to. This is called - "uncharging". The return value of this function indicate the amount - of charges still present in the counter. - - The _locked routines imply that the res_counter->lock is taken. - - e. u64 res_counter_uncharge_until - (struct res_counter *rc, struct res_counter *top, - unsigned long val) - - Almost same as res_counter_uncharge() but propagation of uncharge - stops when rc == top. This is useful when kill a res_counter in - child cgroup. - - 2.1 Other accounting routines - - There are more routines that may help you with common needs, like - checking whether the limit is reached or resetting the max_usage - value. They are all declared in include/linux/res_counter.h. - - - -3. Analyzing the resource counter registrations - - a. If the failcnt value constantly grows, this means that the counter's - limit is too tight. Either the group is misbehaving and consumes too - many resources, or the configuration is not suitable for the group - and the limit should be increased. - - b. The max_usage value can be used to quickly tune the group. One may - set the limits to maximal values and either load the container with - a common pattern or leave one for a while. After this the max_usage - value shows the amount of memory the container would require during - its common activity. - - Setting the limit a bit above this value gives a pretty good - configuration that works in most of the cases. - - c. If the max_usage is much less than the limit, but the failcnt value - is growing, then the group tries to allocate a big chunk of resource - at once. - - d. If the max_usage is much less than the limit, but the failcnt value - is 0, then this group is given too high limit, that it does not - require. It is better to lower the limit a bit leaving more resource - for other groups. - - - -4. Communication with the control groups subsystem (cgroups) - -All the resource controllers that are using cgroups and resource counters -should provide files (in the cgroup filesystem) to work with the resource -counter fields. They are recommended to adhere to the following rules: - - a. File names - - Field name File name - --------------------------------------------------- - usage usage_in_<unit_of_measurement> - max_usage max_usage_in_<unit_of_measurement> - limit limit_in_<unit_of_measurement> - failcnt failcnt - lock no file :) - - b. Reading from file should show the corresponding field value in the - appropriate format. - - c. Writing to file - - Field Expected behavior - ---------------------------------- - usage prohibited - max_usage reset to usage - limit set the limit - failcnt reset to zero - - - -5. Usage example - - a. Declare a task group (take a look at cgroups subsystem for this) and - fold a res_counter into it - - struct my_group { - struct res_counter res; - - <other fields> - } - - b. Put hooks in resource allocation/release paths - - int alloc_something(...) - { - if (res_counter_charge(res_counter_ptr, amount) < 0) - return -ENOMEM; - - <allocate the resource and return to the caller> - } - - void release_something(...) - { - res_counter_uncharge(res_counter_ptr, amount); - - <release the resource> - } - - In order to keep the usage value self-consistent, both the - "res_counter_ptr" and the "amount" in release_something() should be - the same as they were in the alloc_something() when the releasing - resource was allocated. - - c. Provide the way to read res_counter values and set them (the cgroups - still can help with it). - - c. Compile and run :) diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h deleted file mode 100644 index 56b7bc32db4f..000000000000 --- a/include/linux/res_counter.h +++ /dev/null @@ -1,223 +0,0 @@ -#ifndef __RES_COUNTER_H__ -#define __RES_COUNTER_H__ - -/* - * Resource Counters - * Contain common data types and routines for resource accounting - * - * Copyright 2007 OpenVZ SWsoft Inc - * - * Author: Pavel Emelianov <xemul@openvz.org> - * - * See Documentation/cgroups/resource_counter.txt for more - * info about what this counter is. - */ - -#include <linux/spinlock.h> -#include <linux/errno.h> - -/* - * The core object. the cgroup that wishes to account for some - * resource may include this counter into its structures and use - * the helpers described beyond - */ - -struct res_counter { - /* - * the current resource consumption level - */ - unsigned long long usage; - /* - * the maximal value of the usage from the counter creation - */ - unsigned long long max_usage; - /* - * the limit that usage cannot exceed - */ - unsigned long long limit; - /* - * the limit that usage can be exceed - */ - unsigned long long soft_limit; - /* - * the number of unsuccessful attempts to consume the resource - */ - unsigned long long failcnt; - /* - * the lock to protect all of the above. - * the routines below consider this to be IRQ-safe - */ - spinlock_t lock; - /* - * Parent counter, used for hierarchial resource accounting - */ - struct res_counter *parent; -}; - -#define RES_COUNTER_MAX ULLONG_MAX - -/** - * Helpers to interact with userspace - * res_counter_read_u64() - returns the value of the specified member. - * res_counter_read/_write - put/get the specified fields from the - * res_counter struct to/from the user - * - * @counter: the counter in question - * @member: the field to work with (see RES_xxx below) - * @buf: the buffer to opeate on,... - * @nbytes: its size... - * @pos: and the offset. - */ - -u64 res_counter_read_u64(struct res_counter *counter, int member); - -ssize_t res_counter_read(struct res_counter *counter, int member, - const char __user *buf, size_t nbytes, loff_t *pos, - int (*read_strategy)(unsigned long long val, char *s)); - -int res_counter_memparse_write_strategy(const char *buf, - unsigned long long *res); - -/* - * the field descriptors. one for each member of res_counter - */ - -enum { - RES_USAGE, - RES_MAX_USAGE, - RES_LIMIT, - RES_FAILCNT, - RES_SOFT_LIMIT, -}; - -/* - * helpers for accounting - */ - -void res_counter_init(struct res_counter *counter, struct res_counter *parent); - -/* - * charge - try to consume more resource. - * - * @counter: the counter - * @val: the amount of the resource. each controller defines its own - * units, e.g. numbers, bytes, Kbytes, etc - * - * returns 0 on success and <0 if the counter->usage will exceed the - * counter->limit - * - * charge_nofail works the same, except that it charges the resource - * counter unconditionally, and returns < 0 if the after the current - * charge we are over limit. - */ - -int __must_check res_counter_charge(struct res_counter *counter, - unsigned long val, struct res_counter **limit_fail_at); -int res_counter_charge_nofail(struct res_counter *counter, - unsigned long val, struct res_counter **limit_fail_at); - -/* - * uncharge - tell that some portion of the resource is released - * - * @counter: the counter - * @val: the amount of the resource - * - * these calls check for usage underflow and show a warning on the console - * - * returns the total charges still present in @counter. - */ - -u64 res_counter_uncharge(struct res_counter *counter, unsigned long val); - -u64 res_counter_uncharge_until(struct res_counter *counter, - struct res_counter *top, - unsigned long val); -/** - * res_counter_margin - calculate chargeable space of a counter - * @cnt: the counter - * - * Returns the difference between the hard limit and the current usage - * of resource counter @cnt. - */ -static inline unsigned long long res_counter_margin(struct res_counter *cnt) -{ - unsigned long long margin; - unsigned long flags; - - spin_lock_irqsave(&cnt->lock, flags); - if (cnt->limit > cnt->usage) - margin = cnt->limit - cnt->usage; - else - margin = 0; - spin_unlock_irqrestore(&cnt->lock, flags); - return margin; -} - -/** - * Get the difference between the usage and the soft limit - * @cnt: The counter - * - * Returns 0 if usage is less than or equal to soft limit - * The difference between usage and soft limit, otherwise. - */ -static inline unsigned long long -res_counter_soft_limit_excess(struct res_counter *cnt) -{ - unsigned long long excess; - unsigned long flags; - - spin_lock_irqsave(&cnt->lock, flags); - if (cnt->usage <= cnt->soft_limit) - excess = 0; - else - excess = cnt->usage - cnt->soft_limit; - spin_unlock_irqrestore(&cnt->lock, flags); - return excess; -} - -static inline void res_counter_reset_max(struct res_counter *cnt) -{ - unsigned long flags; - - spin_lock_irqsave(&cnt->lock, flags); - cnt->max_usage = cnt->usage; - spin_unlock_irqrestore(&cnt->lock, flags); -} - -static inline void res_counter_reset_failcnt(struct res_counter *cnt) -{ - unsigned long flags; - - spin_lock_irqsave(&cnt->lock, flags); - cnt->failcnt = 0; - spin_unlock_irqrestore(&cnt->lock, flags); -} - -static inline int res_counter_set_limit(struct res_counter *cnt, - unsigned long long limit) -{ - unsigned long flags; - int ret = -EBUSY; - - spin_lock_irqsave(&cnt->lock, flags); - if (cnt->usage <= limit) { - cnt->limit = limit; - ret = 0; - } - spin_unlock_irqrestore(&cnt->lock, flags); - return ret; -} - -static inline int -res_counter_set_soft_limit(struct res_counter *cnt, - unsigned long long soft_limit) -{ - unsigned long flags; - - spin_lock_irqsave(&cnt->lock, flags); - cnt->soft_limit = soft_limit; - spin_unlock_irqrestore(&cnt->lock, flags); - return 0; -} - -#endif diff --git a/init/Kconfig b/init/Kconfig index a60d1442d1df..1761c72bc1a0 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -972,12 +972,6 @@ config CGROUP_CPUACCT Provides a simple Resource Controller for monitoring the total CPU consumed by the tasks in a cgroup. -config RESOURCE_COUNTERS - bool "Resource counters" - help - This option enables controller independent resource accounting - infrastructure that works with cgroups. - config PAGE_COUNTER bool 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; -} |