>From c598d3bbb8b5e900ad0f8397b1acbe922003ac5d Mon Sep 17 00:00:00 2001
From: Xiaotian Feng <dfeng@xxxxxxxxxx>
Date: Tue, 13 Jul 2010 11:01:48 +0800
Subject: [PATCH 11/30] mm: memory reserve management
Generic reserve management code.
It provides methods to reserve and charge. Upon this, generic alloc/free style
reserve pools could be build, which could fully replace mempool_t
functionality.
It should also allow for a Banker's algorithm replacement of __GFP_NOFAIL.
[dfeng@xxxxxxxxxx: build fix for CONFIG_SLAB]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Signed-off-by: Suresh Jayaraman <sjayaraman@xxxxxxx>
Signed-off-by: Xiaotian Feng <dfeng@xxxxxxxxxx>
---
include/linux/reserve.h | 198 +++++++++++++++
include/linux/slab.h | 25 +-
mm/Makefile | 2 +-
mm/reserve.c | 637 +++++++++++++++++++++++++++++++++++++++++++++++
mm/slub.c | 2 +-
5 files changed, 851 insertions(+), 13 deletions(-)
create mode 100644 include/linux/reserve.h
create mode 100644 mm/reserve.c
diff --git a/include/linux/reserve.h b/include/linux/reserve.h
new file mode 100644
index 0000000..e1d3dbb
--- /dev/null
+++ b/include/linux/reserve.h
@@ -0,0 +1,198 @@
+/*
+ * Memory reserve management.
+ *
+ * Copyright (C) 2007-2008 Red Hat, Inc.,
+ * Peter Zijlstra <pzijlstr@xxxxxxxxxx>
+ *
+ * This file contains the public data structure and API definitions.
+ */
+
+#ifndef _LINUX_RESERVE_H
+#define _LINUX_RESERVE_H
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+#include <linux/slab.h>
+
+struct mem_reserve {
+ struct mem_reserve *parent;
+ struct list_head children;
+ struct list_head siblings;
+
+ const char *name;
+
+ long pages;
+ long limit;
+ long usage;
+ spinlock_t lock; /* protects limit and usage */
+
+ wait_queue_head_t waitqueue;
+};
+
+extern struct mem_reserve mem_reserve_root;
+
+void mem_reserve_init(struct mem_reserve *res, const char *name,
+ struct mem_reserve *parent);
+int mem_reserve_connect(struct mem_reserve *new_child,
+ struct mem_reserve *node);
+void mem_reserve_disconnect(struct mem_reserve *node);
+
+int mem_reserve_pages_set(struct mem_reserve *res, long pages);
+int mem_reserve_pages_add(struct mem_reserve *res, long pages);
+int mem_reserve_pages_charge(struct mem_reserve *res, long pages);
+
+int mem_reserve_kmalloc_set(struct mem_reserve *res, long bytes);
+int mem_reserve_kmalloc_charge(struct mem_reserve *res, long bytes);
+
+struct kmem_cache;
+
+int mem_reserve_kmem_cache_set(struct mem_reserve *res,
+ struct kmem_cache *s,
+ int objects);
+int mem_reserve_kmem_cache_charge(struct mem_reserve *res,
+ struct kmem_cache *s, long objs);
+
+void *___kmalloc_reserve(size_t size, gfp_t flags, int node, unsigned long ip,
+ struct mem_reserve *res, int *emerg);
+
+static inline
+void *__kmalloc_reserve(size_t size, gfp_t flags, int node, unsigned long ip,
+ struct mem_reserve *res, int *emerg)
+{
+ void *obj;
+
+ obj = __kmalloc_node_track_caller(size,
+ flags | __GFP_NOMEMALLOC | __GFP_NOWARN, node, ip);
+ if (!obj)
+ obj = ___kmalloc_reserve(size, flags, node, ip, res, emerg);
+
+ return obj;
+}
+
+/**
+ * kmalloc_reserve() - kmalloc() and charge against @res for @emerg allocations
+ * @size - size of the requested memory region
+ * @gfp - allocation flags to use for this allocation
+ * @node - preferred memory node for this allocation
+ * @res - reserve to charge emergency allocations against
+ * @emerg - bit 0 is set when the allocation was an emergency allocation
+ *
+ * Returns NULL on failure
+ */
+#define kmalloc_reserve(size, gfp, node, res, emerg) \
+ __kmalloc_reserve(size, gfp, node, \
+ _RET_IP_, res, emerg)
+
+void __kfree_reserve(void *obj, struct mem_reserve *res, int emerg);
+
+/**
+ * kfree_reserve() - kfree() and uncharge against @res for @emerg allocations
+ * @obj - memory to free
+ * @res - reserve to uncharge emergency allocations from
+ * @emerg - was this an emergency allocation
+ */
+static inline
+void kfree_reserve(void *obj, struct mem_reserve *res, int emerg)
+{
+ if (unlikely(obj && res && emerg))
+ __kfree_reserve(obj, res, emerg);
+ else
+ kfree(obj);
+}
+
+void *__kmem_cache_alloc_reserve(struct kmem_cache *s, gfp_t flags, int node,
+ struct mem_reserve *res, int *emerg);
+
+/**
+ * kmem_cache_alloc_reserve() - kmem_cache_alloc() and charge against @res
+ * @s - kmem_cache to allocate from
+ * @gfp - allocation flags to use for this allocation
+ * @node - preferred memory node for this allocation
+ * @res - reserve to charge emergency allocations against
+ * @emerg - bit 0 is set when the allocation was an emergency allocation
+ *
+ * Returns NULL on failure
+ */
+static inline
+void *kmem_cache_alloc_reserve(struct kmem_cache *s, gfp_t flags, int node,
+ struct mem_reserve *res, int *emerg)
+{
+ void *obj;
+
+ obj = kmem_cache_alloc_node(s,
+ flags | __GFP_NOMEMALLOC | __GFP_NOWARN, node);
+ if (!obj)
+ obj = __kmem_cache_alloc_reserve(s, flags, node, res, emerg);
+
+ return obj;
+}
+
+void __kmem_cache_free_reserve(struct kmem_cache *s, void *obj,
+ struct mem_reserve *res, int emerg);
+
+/**
+ * kmem_cache_free_reserve() - kmem_cache_free() and uncharge against @res
+ * @s - kmem_cache to free to
+ * @obj - memory to free
+ * @res - reserve to uncharge emergency allocations from
+ * @emerg - was this an emergency allocation
+ */
+static inline
+void kmem_cache_free_reserve(struct kmem_cache *s, void *obj,
+ struct mem_reserve *res, int emerg)
+{
+ if (unlikely(obj && res && emerg))
+ __kmem_cache_free_reserve(s, obj, res, emerg);
+ else
+ kmem_cache_free(s, obj);
+}
+
+struct page *__alloc_pages_reserve(int node, gfp_t flags, int order,
+ struct mem_reserve *res, int *emerg);
+
+/**
+ * alloc_pages_reserve() - alloc_pages() and charge against @res
+ * @node - preferred memory node for this allocation
+ * @gfp - allocation flags to use for this allocation
+ * @order - page order
+ * @res - reserve to charge emergency allocations against
+ * @emerg - bit 0 is set when the allocation was an emergency allocation
+ *
+ * Returns NULL on failure
+ */
+static inline
+struct page *alloc_pages_reserve(int node, gfp_t flags, int order,
+ struct mem_reserve *res, int *emerg)
+{
+ struct page *page;
+
+ page = alloc_pages_node(node,
+ flags | __GFP_NOMEMALLOC | __GFP_NOWARN, order);
+ if (!page)
+ page = __alloc_pages_reserve(node, flags, order, res, emerg);
+
+ return page;
+}
+
+void __free_pages_reserve(struct page *page, int order,
+ struct mem_reserve *res, int emerg);
+
+/**
+ * free_pages_reserve() - __free_pages() and uncharge against @res
+ * @page - page to free
+ * @order - page order
+ * @res - reserve to uncharge emergency allocations from
+ * @emerg - was this an emergency allocation
+ */
+static inline
+void free_pages_reserve(struct page *page, int order,
+ struct mem_reserve *res, int emerg)
+{
+ if (unlikely(page && res && emerg))
+ __free_pages_reserve(page, order, res, emerg);
+ else
+ __free_pages(page, order);
+}
+
+#endif /* _LINUX_RESERVE_H */
diff --git a/include/linux/slab.h b/include/linux/slab.h
index b57b9ca..68195a7 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -272,15 +272,17 @@ static inline void *kmem_cache_alloc_node(struct kmem_cache *cachep,
* allocator where we care about the real place the memory allocation
* request comes from.
*/
-#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
+#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \
+ (defined(CONFIG_SLAB) && defined(CONFIG_TRACING))
extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
-#define kmalloc_track_caller(size, flags) \
- __kmalloc_track_caller(size, flags, _RET_IP_)
#else
-#define kmalloc_track_caller(size, flags) \
+#define __kmalloc_track_caller(size, flags, ip) \
__kmalloc(size, flags)
#endif /* DEBUG_SLAB */
+#define kmalloc_track_caller(size, flags) \
+ __kmalloc_track_caller(size, flags, _RET_IP_)
+
#ifdef CONFIG_NUMA
/*
* kmalloc_node_track_caller is a special version of kmalloc_node that
@@ -290,23 +292,24 @@ extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
* standard allocator where we care about the real place the memory
* allocation request comes from.
*/
-#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB)
+#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \
+ (defined(CONFIG_SLAB) && defined(CONFIG_TRACING))
extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
-#define kmalloc_node_track_caller(size, flags, node) \
- __kmalloc_node_track_caller(size, flags, node, \
- _RET_IP_)
#else
-#define kmalloc_node_track_caller(size, flags, node) \
+#define __kmalloc_node_track_caller(size, flags, node, ip) \
__kmalloc_node(size, flags, node)
#endif
#else /* CONFIG_NUMA */
-#define kmalloc_node_track_caller(size, flags, node) \
- kmalloc_track_caller(size, flags)
+#define __kmalloc_node_track_caller(size, flags, node, ip) \
+ __kmalloc_track_caller(size, flags, ip)
#endif /* CONFIG_NUMA */
+#define kmalloc_node_track_caller(size, flags, node) \
+ __kmalloc_node_track_caller(size, flags, node, \
+ _RET_IP_)
/*
* Shortcuts
*/
diff --git a/mm/Makefile b/mm/Makefile
index 8982504..d1717bb 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -11,7 +11,7 @@ obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
maccess.o page_alloc.o page-writeback.o \
readahead.o swap.o truncate.o vmscan.o shmem.o \
prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \
- page_isolation.o mm_init.o mmu_context.o \
+ page_isolation.o mm_init.o mmu_context.o reserve.o \
$(mmu-y)
obj-y += init-mm.o
diff --git a/mm/reserve.c b/mm/reserve.c
new file mode 100644
index 0000000..2a00d72
--- /dev/null
+++ b/mm/reserve.c
@@ -0,0 +1,637 @@
+/*
+ * Memory reserve management.
+ *
+ * Copyright (C) 2007-2008, Red Hat, Inc.,
+ * Peter Zijlstra <pzijlstr@xxxxxxxxxx>
+ *
+ * Description:
+ *
+ * Manage a set of memory reserves.
+ *
+ * A memory reserve is a reserve for a specified number of object of specified
+ * size. Since memory is managed in pages, this reserve demand is then
+ * translated into a page unit.
+ *
+ * So each reserve has a specified object limit, an object usage count and a
+ * number of pages required to back these objects.
+ *
+ * Usage is charged against a reserve, if the charge fails, the resource must
+ * not be allocated/used.
+ *
+ * The reserves are managed in a tree, and the resource demands (pages and
+ * limit) are propagated up the tree. Obviously the object limit will be
+ * meaningless as soon as the unit starts mixing, but the required page reserve
+ * (being of one unit) is still valid at the root.
+ *
+ * It is the page demand of the root node that is used to set the global
+ * reserve (adjust_memalloc_reserve() which sets zone->pages_emerg).
+ *
+ * As long as a subtree has the same usage unit, an aggregate node can be used
+ * to charge against, instead of the leaf nodes. However, do be consistent with
+ * who is charged, resource usage is not propagated up the tree (for
+ * performance reasons).
+ */
+
+#include <linux/reserve.h>
+#include <linux/mutex.h>
+#include <linux/mmzone.h>
+#include <linux/log2.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include "internal.h"
+
+static DEFINE_MUTEX(mem_reserve_mutex);
+
+/**
+ * @mem_reserve_root - the global reserve root
+ *
+ * The global reserve is empty, and has no limit unit, it merely
+ * acts as an aggregation point for reserves and an interface to
+ * adjust_memalloc_reserve().
+ */
+struct mem_reserve mem_reserve_root = {
+ .children = LIST_HEAD_INIT(mem_reserve_root.children),
+ .siblings = LIST_HEAD_INIT(mem_reserve_root.siblings),
+ .name = "total reserve",
+ .lock = __SPIN_LOCK_UNLOCKED(mem_reserve_root.lock),
+ .waitqueue = __WAIT_QUEUE_HEAD_INITIALIZER(mem_reserve_root.waitqueue),
+};
+EXPORT_SYMBOL_GPL(mem_reserve_root);
+
+/**
+ * mem_reserve_init() - initialize a memory reserve object
+ * @res - the new reserve object
+ * @name - a name for this reserve
+ * @parent - when non NULL, the parent to connect to.
+ */
+void mem_reserve_init(struct mem_reserve *res, const char *name,
+ struct mem_reserve *parent)
+{
+ memset(res, 0, sizeof(*res));
+ INIT_LIST_HEAD(&res->children);
+ INIT_LIST_HEAD(&res->siblings);
+ res->name = name;
+ spin_lock_init(&res->lock);
+ init_waitqueue_head(&res->waitqueue);
+
+ if (parent)
+ mem_reserve_connect(res, parent);
+}
+EXPORT_SYMBOL_GPL(mem_reserve_init);
+
+/*
+ * propagate the pages and limit changes up the (sub)tree.
+ */
+static void __calc_reserve(struct mem_reserve *res, long pages, long limit)
+{
+ unsigned long flags;
+
+ for ( ; res; res = res->parent) {
+ res->pages += pages;
+
+ if (limit) {
+ spin_lock_irqsave(&res->lock, flags);
+ res->limit += limit;
+ spin_unlock_irqrestore(&res->lock, flags);
+ }
+ }
+}
+
+/**
+ * __mem_reserve_add() - primitive to change the size of a reserve
+ * @res - reserve to change
+ * @pages - page delta
+ * @limit - usage limit delta
+ *
+ * Returns -ENOMEM when a size increase is not possible atm.
+ */
+static int __mem_reserve_add(struct mem_reserve *res, long pages, long limit)
+{
+ int ret = 0;
+ long reserve;
+
+ /*
+ * This looks more complex than need be, that is because we handle
+ * the case where @res isn't actually connected to mem_reserve_root.
+ *
+ * So, by propagating the new pages up the (sub)tree and computing
+ * the difference in mem_reserve_root.pages we find if this action
+ * affects the actual reserve.
+ *
+ * The (partial) propagation also makes that mem_reserve_connect()
+ * needs only look at the direct child, since each disconnected
+ * sub-tree is fully up-to-date.
+ */
+ reserve = mem_reserve_root.pages;
+ __calc_reserve(res, pages, 0);
+ reserve = mem_reserve_root.pages - reserve;
+
+ if (reserve) {
+ ret = adjust_memalloc_reserve(reserve);
+ if (ret)
+ __calc_reserve(res, -pages, 0);
+ }
+
+ /*
+ * Delay updating the limits until we've acquired the resources to
+ * back it.
+ */
+ if (!ret)
+ __calc_reserve(res, 0, limit);
+
+ return ret;
+}
+
+/**
+ * __mem_reserve_charge() - primitive to charge object usage of a reserve
+ * @res - reserve to charge
+ * @charge - size of the charge
+ *
+ * Returns non-zero on success, zero on failure.
+ */
+static
+int __mem_reserve_charge(struct mem_reserve *res, long charge)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&res->lock, flags);
+ if (charge < 0 || res->usage + charge < res->limit) {
+ res->usage += charge;
+ if (unlikely(res->usage < 0))
+ res->usage = 0;
+ ret = 1;
+ }
+ if (charge < 0)
+ wake_up_all(&res->waitqueue);
+ spin_unlock_irqrestore(&res->lock, flags);
+
+ return ret;
+}
+
+/**
+ * mem_reserve_connect() - connect a reserve to another in a child-parent relation
+ * @new_child - the reserve node to connect (child)
+ * @node - the reserve node to connect to (parent)
+ *
+ * Connecting a node results in an increase of the reserve by the amount of
+ * pages in @new_child->pages if @node has a connection to mem_reserve_root.
+ *
+ * Returns -ENOMEM when the new connection would increase the reserve (parent
+ * is connected to mem_reserve_root) and there is no memory to do so.
+ *
+ * On error, the child is _NOT_ connected.
+ */
+int mem_reserve_connect(struct mem_reserve *new_child, struct mem_reserve *node)
+{
+ int ret;
+
+ WARN_ON(!new_child->name);
+
+ mutex_lock(&mem_reserve_mutex);
+ if (new_child->parent) {
+ ret = -EEXIST;
+ goto unlock;
+ }
+ new_child->parent = node;
+ list_add(&new_child->siblings, &node->children);
+ ret = __mem_reserve_add(node, new_child->pages, new_child->limit);
+ if (ret) {
+ new_child->parent = NULL;
+ list_del_init(&new_child->siblings);
+ }
+unlock:
+ mutex_unlock(&mem_reserve_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mem_reserve_connect);
+
+/**
+ * mem_reserve_disconnect() - sever a nodes connection to the reserve tree
+ * @node - the node to disconnect
+ *
+ * Disconnecting a node results in a reduction of the reserve by @node->pages
+ * if node had a connection to mem_reserve_root.
+ */
+void mem_reserve_disconnect(struct mem_reserve *node)
+{
+ int ret;
+
+ BUG_ON(!node->parent);
+
+ mutex_lock(&mem_reserve_mutex);
+ if (!node->parent) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+ ret = __mem_reserve_add(node->parent, -node->pages, -node->limit);
+ if (!ret) {
+ node->parent = NULL;
+ list_del_init(&node->siblings);
+ }
+unlock:
+ mutex_unlock(&mem_reserve_mutex);
+
+ /*
+ * We cannot fail to shrink the reserves, can we?
+ */
+ WARN_ON(ret);
+}
+EXPORT_SYMBOL_GPL(mem_reserve_disconnect);
+
+#ifdef CONFIG_PROC_FS
+
+/*
+ * Simple output of the reserve tree in: /proc/reserve_info
+ * Example:
+ *
+ * localhost ~ # cat /proc/reserve_info
+ * 1:0 "total reserve" 6232K 0/278581
+ * 2:1 "total network reserve" 6232K 0/278581
+ * 3:2 "network TX reserve" 212K 0/53
+ * 4:3 "protocol TX pages" 212K 0/53
+ * 5:2 "network RX reserve" 6020K 0/278528
+ * 6:5 "IPv4 route cache" 5508K 0/16384
+ * 7:5 "SKB data reserve" 512K 0/262144
+ * 8:7 "IPv4 fragment cache" 512K 0/262144
+ */
+
+static void mem_reserve_show_item(struct seq_file *m, struct mem_reserve *res,
+ unsigned int parent, unsigned int *id)
+{
+ struct mem_reserve *child;
+ unsigned int my_id = ++*id;
+
+ seq_printf(m, "%d:%d \"%s\" %ldK %ld/%ld\n",
+ my_id, parent, res->name,
+ res->pages << (PAGE_SHIFT - 10),
+ res->usage, res->limit);
+
+ list_for_each_entry(child, &res->children, siblings)
+ mem_reserve_show_item(m, child, my_id, id);
+}
+
+static int mem_reserve_show(struct seq_file *m, void *v)
+{
+ unsigned int ident = 0;
+
+ mutex_lock(&mem_reserve_mutex);
+ mem_reserve_show_item(m, &mem_reserve_root, ident, &ident);
+ mutex_unlock(&mem_reserve_mutex);
+
+ return 0;
+}
+
+static int mem_reserve_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, mem_reserve_show, NULL);
+}
+
+static const struct file_operations mem_reserve_opterations = {
+ .open = mem_reserve_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static __init int mem_reserve_proc_init(void)
+{
+ proc_create("reserve_info", S_IRUSR, NULL, &mem_reserve_opterations);
+ return 0;
+}
+
+module_init(mem_reserve_proc_init);
+
+#endif
+
+/*
+ * alloc_page helpers
+ */
+
+/**
+ * mem_reserve_pages_set() - set reserves size in pages
+ * @res - reserve to set
+ * @pages - size in pages to set it to
+ *
+ * Returns -ENOMEM when it fails to set the reserve. On failure the old size
+ * is preserved.
+ */
+int mem_reserve_pages_set(struct mem_reserve *res, long pages)
+{
+ int ret;
+
+ mutex_lock(&mem_reserve_mutex);
+ pages -= res->pages;
+ ret = __mem_reserve_add(res, pages, pages * PAGE_SIZE);
+ mutex_unlock(&mem_reserve_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mem_reserve_pages_set);
+
+/**
+ * mem_reserve_pages_add() - change the size in a relative way
+ * @res - reserve to change
+ * @pages - number of pages to add (or subtract when negative)
+ *
+ * Similar to mem_reserve_pages_set, except that the argument is relative
+ * instead of absolute.
+ *
+ * Returns -ENOMEM when it fails to increase.
+ */
+int mem_reserve_pages_add(struct mem_reserve *res, long pages)
+{
+ int ret;
+
+ mutex_lock(&mem_reserve_mutex);
+ ret = __mem_reserve_add(res, pages, pages * PAGE_SIZE);
+ mutex_unlock(&mem_reserve_mutex);
+
+ return ret;
+}
+
+/**
+ * mem_reserve_pages_charge() - charge page usage to a reserve
+ * @res - reserve to charge
+ * @pages - size to charge
+ *
+ * Returns non-zero on success.
+ */
+int mem_reserve_pages_charge(struct mem_reserve *res, long pages)
+{
+ return __mem_reserve_charge(res, pages * PAGE_SIZE);
+}
+EXPORT_SYMBOL_GPL(mem_reserve_pages_charge);
+
+/*
+ * kmalloc helpers
+ */
+
+/**
+ * mem_reserve_kmalloc_set() - set this reserve to bytes worth of kmalloc
+ * @res - reserve to change
+ * @bytes - size in bytes to reserve
+ *
+ * Returns -ENOMEM on failure.
+ */
+int mem_reserve_kmalloc_set(struct mem_reserve *res, long bytes)
+{
+ int ret;
+ long pages;
+
+ mutex_lock(&mem_reserve_mutex);
+ pages = kmalloc_estimate_bytes(GFP_ATOMIC, bytes);
+ pages -= res->pages;
+ bytes -= res->limit;
+ ret = __mem_reserve_add(res, pages, bytes);
+ mutex_unlock(&mem_reserve_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mem_reserve_kmalloc_set);
+
+/**
+ * mem_reserve_kmalloc_charge() - charge bytes to a reserve
+ * @res - reserve to charge
+ * @bytes - bytes to charge
+ *
+ * Returns non-zero on success.
+ */
+int mem_reserve_kmalloc_charge(struct mem_reserve *res, long bytes)
+{
+ if (bytes < 0)
+ bytes = -roundup_pow_of_two(-bytes);
+ else
+ bytes = roundup_pow_of_two(bytes);
+
+ return __mem_reserve_charge(res, bytes);
+}
+EXPORT_SYMBOL_GPL(mem_reserve_kmalloc_charge);
+
+/*
+ * kmem_cache helpers
+ */
+
+/**
+ * mem_reserve_kmem_cache_set() - set reserve to @objects worth of kmem_cache_alloc of @s
+ * @res - reserve to set
+ * @s - kmem_cache to reserve from
+ * @objects - number of objects to reserve
+ *
+ * Returns -ENOMEM on failure.
+ */
+int mem_reserve_kmem_cache_set(struct mem_reserve *res, struct kmem_cache *s,
+ int objects)
+{
+ int ret;
+ long pages, bytes;
+
+ mutex_lock(&mem_reserve_mutex);
+ pages = kmem_alloc_estimate(s, GFP_ATOMIC, objects);
+ pages -= res->pages;
+ bytes = objects * kmem_cache_size(s) - res->limit;
+ ret = __mem_reserve_add(res, pages, bytes);
+ mutex_unlock(&mem_reserve_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mem_reserve_kmem_cache_set);
+
+/**
+ * mem_reserve_kmem_cache_charge() - charge (or uncharge) usage of objs
+ * @res - reserve to charge
+ * @objs - objects to charge for
+ *
+ * Returns non-zero on success.
+ */
+int mem_reserve_kmem_cache_charge(struct mem_reserve *res, struct kmem_cache *s,
+ long objs)
+{
+ return __mem_reserve_charge(res, objs * kmem_cache_size(s));
+}
+EXPORT_SYMBOL_GPL(mem_reserve_kmem_cache_charge);
+
+/*
+ * Alloc wrappers.
+ *
+ * Actual usage is commented in linux/reserve.h where the interface functions
+ * live. Furthermore, the code is 3 instances of the same paradigm, hence only
+ * the first contains extensive comments.
+ */
+
+/*
+ * kmalloc/kfree
+ */
+
+void *___kmalloc_reserve(size_t size, gfp_t flags, int node, unsigned long ip,
+ struct mem_reserve *res, int *emerg)
+{
+ void *obj;
+ gfp_t gfp;
+
+ /*
+ * Try a regular allocation, when that fails and we're not entitled
+ * to the reserves, fail.
+ */
+ gfp = flags | __GFP_NOMEMALLOC | __GFP_NOWARN;
+ obj = __kmalloc_node_track_caller(size, gfp, node, ip);
+
+ if (obj || !(gfp_to_alloc_flags(flags) & ALLOC_NO_WATERMARKS))
+ goto out;
+
+ /*
+ * If we were given a reserve to charge against, try that.
+ */
+ if (res && !mem_reserve_kmalloc_charge(res, size)) {
+ /*
+ * If we failed to charge and we're not allowed to wait for
+ * it to succeed, bail.
+ */
+ if (!(flags & __GFP_WAIT))
+ goto out;
+
+ /*
+ * Wait for a successfull charge against the reserve. All
+ * uncharge operations against this reserve will wake us up.
+ */
+ wait_event(res->waitqueue,
+ mem_reserve_kmalloc_charge(res, size));
+
+ /*
+ * After waiting for it, again try a regular allocation.
+ * Pressure could have lifted during our sleep. If this
+ * succeeds, uncharge the reserve.
+ */
+ obj = __kmalloc_node_track_caller(size, gfp, node, ip);
+ if (obj) {
+ mem_reserve_kmalloc_charge(res, -size);
+ goto out;
+ }
+ }
+
+ /*
+ * Regular allocation failed, and we've successfully charged our
+ * requested usage against the reserve. Do the emergency allocation.
+ */
+ obj = __kmalloc_node_track_caller(size, flags, node, ip);
+ WARN_ON(!obj);
+ if (emerg)
+ *emerg = 1;
+
+out:
+ return obj;
+}
+
+void __kfree_reserve(void *obj, struct mem_reserve *res, int emerg)
+{
+ /*
+ * ksize gives the full allocated size vs the requested size we used to
+ * charge; however since we round up to the nearest power of two, this
+ * should all work nicely.
+ */
+ size_t size = ksize(obj);
+
+ kfree(obj);
+ /*
+ * Free before uncharge, this ensures memory is actually present when
+ * a subsequent charge succeeds.
+ */
+ mem_reserve_kmalloc_charge(res, -size);
+}
+
+/*
+ * kmem_cache_alloc/kmem_cache_free
+ */
+
+void *__kmem_cache_alloc_reserve(struct kmem_cache *s, gfp_t flags, int node,
+ struct mem_reserve *res, int *emerg)
+{
+ void *obj;
+ gfp_t gfp;
+
+ gfp = flags | __GFP_NOMEMALLOC | __GFP_NOWARN;
+ obj = kmem_cache_alloc_node(s, gfp, node);
+
+ if (obj || !(gfp_to_alloc_flags(flags) & ALLOC_NO_WATERMARKS))
+ goto out;
+
+ if (res && !mem_reserve_kmem_cache_charge(res, s, 1)) {
+ if (!(flags & __GFP_WAIT))
+ goto out;
+
+ wait_event(res->waitqueue,
+ mem_reserve_kmem_cache_charge(res, s, 1));
+
+ obj = kmem_cache_alloc_node(s, gfp, node);
+ if (obj) {
+ mem_reserve_kmem_cache_charge(res, s, -1);
+ goto out;
+ }
+ }
+
+ obj = kmem_cache_alloc_node(s, flags, node);
+ WARN_ON(!obj);
+ if (emerg)
+ *emerg = 1;
+
+out:
+ return obj;
+}
+
+void __kmem_cache_free_reserve(struct kmem_cache *s, void *obj,
+ struct mem_reserve *res, int emerg)
+{
+ kmem_cache_free(s, obj);
+ mem_reserve_kmem_cache_charge(res, s, -1);
+}
+
+/*
+ * alloc_pages/free_pages
+ */
+
+struct page *__alloc_pages_reserve(int node, gfp_t flags, int order,
+ struct mem_reserve *res, int *emerg)
+{
+ struct page *page;
+ gfp_t gfp;
+ long pages = 1 << order;
+
+ gfp = flags | __GFP_NOMEMALLOC | __GFP_NOWARN;
+ page = alloc_pages_node(node, gfp, order);
+
+ if (page || !(gfp_to_alloc_flags(flags) & ALLOC_NO_WATERMARKS))
+ goto out;
+
+ if (res && !mem_reserve_pages_charge(res, pages)) {
+ if (!(flags & __GFP_WAIT))
+ goto out;
+
+ wait_event(res->waitqueue,
+ mem_reserve_pages_charge(res, pages));
+
+ page = alloc_pages_node(node, gfp, order);
+ if (page) {
+ mem_reserve_pages_charge(res, -pages);
+ goto out;
+ }
+ }
+
+ page = alloc_pages_node(node, flags, order);
+ WARN_ON(!page);
+ if (emerg)
+ *emerg = 1;
+
+out:
+ return page;
+}
+
+void __free_pages_reserve(struct page *page, int order,
+ struct mem_reserve *res, int emerg)
+{
+ __free_pages(page, order);
+ mem_reserve_pages_charge(res, -(1 << order));
+}
diff --git a/mm/slub.c b/mm/slub.c
index 056545e..ffcd315 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2799,6 +2799,7 @@ void *__kmalloc(size_t size, gfp_t flags)
}
EXPORT_SYMBOL(__kmalloc);
+#ifdef CONFIG_NUMA
static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
{
struct page *page;
@@ -2813,7 +2814,6 @@ static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
return ptr;
}
-#ifdef CONFIG_NUMA
void *__kmalloc_node(size_t size, gfp_t flags, int node)
{
struct kmem_cache *s;
--
1.7.1.1
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