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Commit c89126ea authored by Dan Magenheimer's avatar Dan Magenheimer Committed by Greg Kroah-Hartman
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staging: ramster: ramster-specific changes to zcache/tmem 

RAMster implements peer-to-peer transcendent memory, allowing a "cluster"
of kernels to dynamically pool their RAM.

This patch incorporates changes transforming zcache to work with
a remote store.

In tmem.[ch], new "repatriate" (provoke async get) and "localify" (handle
incoming data resulting from an async get) routines combine with a handful
of changes to existing pamops interfaces allow the generic tmem code
to support asynchronous operations.  Also, a new tmem_xhandle struct
groups together key information that must be passed to remote tmem stores.

Zcache-main.c is augmented with a large amount of ramster-specific code
to handle remote operations and "foreign" pages on both ends of the
"remotify" protocol.  New "foreign" pools are auto-created on demand.
A "selfshrinker" thread periodically repatriates remote persistent pages
when local memory conditions allow.  For certain operations, a queue is
necessary to guarantee strict ordering as out-of-order puts/flushes can
cause strange race conditions.  Pampd pointers now either point to local
memory OR describe a remote page; to allow the same 64-bits to describe
either, the LSB is used to differentiate.  Some acrobatics must be performed
to ensure local memory is available to handle a remote persistent get,
or deal with the data directly anyway if the malloc failed.  Lots
of ramster-specific statistics are available via sysfs.

Note: Some debug ifdefs left in for now.
Signed-off-by: default avatarDan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent b95e141a
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Showing with 1741 additions and 292 deletions
drivers/staging/ramster/Kconfig
View file @ c89126ea
config ZCACHE
tristate "Dynamic compression of swap pages and clean pagecache pages"
depends on CLEANCACHE || FRONTSWAP
select XVMALLOC
config RAMSTER
bool "Cross-machine RAM capacity sharing, aka peer-to-peer tmem"
depends on (CLEANCACHE || FRONTSWAP) && CONFIGFS_FS && !ZCACHE && !XVMALLOC && !HIGHMEM
select LZO_COMPRESS
select LZO_DECOMPRESS
default n
help
Zcache doubles RAM efficiency while providing a significant
performance boosts on many workloads. Zcache uses lzo1x
compression and an in-kernel implementation of transcendent
memory to store clean page cache pages and swap in RAM,
providing a noticeable reduction in disk I/O.
RAMster allows RAM on other machines in a cluster to be utilized
dynamically and symmetrically instead of swapping to a local swap
disk, thus improving performance on memory-constrained workloads
while minimizing total RAM across the cluster. RAMster, like
zcache, compresses swap pages into local RAM, but then remotifies
the compressed pages to another node in the RAMster cluster.
drivers/staging/ramster/Makefile
View file @ c89126ea
zcache-y := zcache-main.o tmem.o
obj-$(CONFIG_ZCACHE) += zcache.o
obj-$(CONFIG_RAMSTER) += zcache-main.o tmem.o r2net.o xvmalloc.o cluster/
drivers/staging/ramster/tmem.c
View file @ c89126ea
......@@ -27,6 +27,7 @@
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <linux/delay.h>
#include "tmem.h"
......@@ -316,7 +317,7 @@ static void *tmem_pampd_lookup_in_obj(struct tmem_obj *obj, uint32_t index)
}
static void *tmem_pampd_replace_in_obj(struct tmem_obj *obj, uint32_t index,
void *new_pampd)
void *new_pampd, bool no_free)
{
struct tmem_objnode **slot;
void *ret = NULL;
......@@ -325,7 +326,9 @@ static void *tmem_pampd_replace_in_obj(struct tmem_obj *obj, uint32_t index,
if ((slot != NULL) && (*slot != NULL)) {
void *old_pampd = *(void **)slot;
*(void **)slot = new_pampd;
(*tmem_pamops.free)(old_pampd, obj->pool, NULL, 0);
if (!no_free)
(*tmem_pamops.free)(old_pampd, obj->pool,
NULL, 0, false);
ret = new_pampd;
}
return ret;
......@@ -481,7 +484,7 @@ static void tmem_objnode_node_destroy(struct tmem_obj *obj,
if (ht == 1) {
obj->pampd_count--;
(*tmem_pamops.free)(objnode->slots[i],
obj->pool, NULL, 0);
obj->pool, NULL, 0, true);
objnode->slots[i] = NULL;
continue;
}
......@@ -498,7 +501,8 @@ static void tmem_pampd_destroy_all_in_obj(struct tmem_obj *obj)
return;
if (obj->objnode_tree_height == 0) {
obj->pampd_count--;
(*tmem_pamops.free)(obj->objnode_tree_root, obj->pool, NULL, 0);
(*tmem_pamops.free)(obj->objnode_tree_root,
obj->pool, NULL, 0, true);
} else {
tmem_objnode_node_destroy(obj, obj->objnode_tree_root,
obj->objnode_tree_height);
......@@ -529,7 +533,7 @@ static void tmem_pampd_destroy_all_in_obj(struct tmem_obj *obj)
* always flushes for simplicity.
*/
int tmem_put(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
char *data, size_t size, bool raw, bool ephemeral)
char *data, size_t size, bool raw, int ephemeral)
{
struct tmem_obj *obj = NULL, *objfound = NULL, *objnew = NULL;
void *pampd = NULL, *pampd_del = NULL;
......@@ -545,7 +549,7 @@ int tmem_put(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
/* if found, is a dup put, flush the old one */
pampd_del = tmem_pampd_delete_from_obj(obj, index);
BUG_ON(pampd_del != pampd);
(*tmem_pamops.free)(pampd, pool, oidp, index);
(*tmem_pamops.free)(pampd, pool, oidp, index, true);
if (obj->pampd_count == 0) {
objnew = obj;
objfound = NULL;
......@@ -576,7 +580,7 @@ int tmem_put(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
(void)tmem_pampd_delete_from_obj(obj, index);
free:
if (pampd)
(*tmem_pamops.free)(pampd, pool, NULL, 0);
(*tmem_pamops.free)(pampd, pool, NULL, 0, true);
if (objnew) {
tmem_obj_free(objnew, hb);
(*tmem_hostops.obj_free)(objnew, pool);
......@@ -586,6 +590,65 @@ int tmem_put(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
return ret;
}
void *tmem_localify_get_pampd(struct tmem_pool *pool, struct tmem_oid *oidp,
uint32_t index, struct tmem_obj **ret_obj,
void **saved_hb)
{
struct tmem_hashbucket *hb;
struct tmem_obj *obj = NULL;
void *pampd = NULL;
hb = &pool->hashbucket[tmem_oid_hash(oidp)];
spin_lock(&hb->lock);
obj = tmem_obj_find(hb, oidp);
if (likely(obj != NULL))
pampd = tmem_pampd_lookup_in_obj(obj, index);
*ret_obj = obj;
*saved_hb = (void *)hb;
/* note, hashbucket remains locked */
return pampd;
}
void tmem_localify_finish(struct tmem_obj *obj, uint32_t index,
void *pampd, void *saved_hb, bool delete)
{
struct tmem_hashbucket *hb = (struct tmem_hashbucket *)saved_hb;
BUG_ON(!spin_is_locked(&hb->lock));
if (pampd != NULL) {
BUG_ON(obj == NULL);
(void)tmem_pampd_replace_in_obj(obj, index, pampd, 1);
} else if (delete) {
BUG_ON(obj == NULL);
(void)tmem_pampd_delete_from_obj(obj, index);
}
spin_unlock(&hb->lock);
}
static int tmem_repatriate(void **ppampd, struct tmem_hashbucket *hb,
struct tmem_pool *pool, struct tmem_oid *oidp,
uint32_t index, bool free, char *data)
{
void *old_pampd = *ppampd, *new_pampd = NULL;
bool intransit = false;
int ret = 0;
if (!is_ephemeral(pool))
new_pampd = (*tmem_pamops.repatriate_preload)(
old_pampd, pool, oidp, index, &intransit);
if (intransit)
ret = -EAGAIN;
else if (new_pampd != NULL)
*ppampd = new_pampd;
/* must release the hb->lock else repatriate can't sleep */
spin_unlock(&hb->lock);
if (!intransit)
ret = (*tmem_pamops.repatriate)(old_pampd, new_pampd, pool,
oidp, index, free, data);
return ret;
}
/*
* "Get" a page, e.g. if one can be found, copy the tmem page with the
* matching handle from PAM space to the kernel. By tmem definition,
......@@ -607,14 +670,36 @@ int tmem_get(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
int ret = -1;
struct tmem_hashbucket *hb;
bool free = (get_and_free == 1) || ((get_and_free == 0) && ephemeral);
bool lock_held = false;
bool lock_held = 0;
void **ppampd;
again:
hb = &pool->hashbucket[tmem_oid_hash(oidp)];
spin_lock(&hb->lock);
lock_held = true;
lock_held = 1;
obj = tmem_obj_find(hb, oidp);
if (obj == NULL)
goto out;
ppampd = __tmem_pampd_lookup_in_obj(obj, index);
if (ppampd == NULL)
goto out;
if (tmem_pamops.is_remote(*ppampd)) {
ret = tmem_repatriate(ppampd, hb, pool, oidp,
index, free, data);
lock_held = 0; /* note hb->lock has been unlocked */
if (ret == -EAGAIN) {
/* rare I think, but should cond_resched()??? */
usleep_range(10, 1000);
goto again;
} else if (ret != 0) {
if (ret != -ENOENT)
pr_err("UNTESTED case in tmem_get, ret=%d\n",
ret);
ret = -1;
goto out;
}
goto out;
}
if (free)
pampd = tmem_pampd_delete_from_obj(obj, index);
else
......@@ -628,10 +713,6 @@ int tmem_get(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
obj = NULL;
}
}
if (tmem_pamops.is_remote(pampd)) {
lock_held = false;
spin_unlock(&hb->lock);
}
if (free)
ret = (*tmem_pamops.get_data_and_free)(
data, size, raw, pampd, pool, oidp, index);
......@@ -668,7 +749,7 @@ int tmem_flush_page(struct tmem_pool *pool,
pampd = tmem_pampd_delete_from_obj(obj, index);
if (pampd == NULL)
goto out;
(*tmem_pamops.free)(pampd, pool, oidp, index);
(*tmem_pamops.free)(pampd, pool, oidp, index, true);
if (obj->pampd_count == 0) {
tmem_obj_free(obj, hb);
(*tmem_hostops.obj_free)(obj, pool);
......@@ -682,8 +763,8 @@ int tmem_flush_page(struct tmem_pool *pool,
/*
* If a page in tmem matches the handle, replace the page so that any
* subsequent "get" gets the new page. Returns 0 if
* there was a page to replace, else returns -1.
* subsequent "get" gets the new page. Returns the new page if
* there was a page to replace, else returns NULL.
*/
int tmem_replace(struct tmem_pool *pool, struct tmem_oid *oidp,
uint32_t index, void *new_pampd)
......@@ -697,7 +778,7 @@ int tmem_replace(struct tmem_pool *pool, struct tmem_oid *oidp,
obj = tmem_obj_find(hb, oidp);
if (obj == NULL)
goto out;
new_pampd = tmem_pampd_replace_in_obj(obj, index, new_pampd);
new_pampd = tmem_pampd_replace_in_obj(obj, index, new_pampd, 0);
ret = (*tmem_pamops.replace_in_obj)(new_pampd, obj);
out:
spin_unlock(&hb->lock);
......
drivers/staging/ramster/tmem.h
View file @ c89126ea
......@@ -9,7 +9,6 @@
#ifndef _TMEM_H_
#define _TMEM_H_
#include <linux/types.h>
#include <linux/highmem.h>
#include <linux/hash.h>
#include <linux/atomic.h>
......@@ -89,6 +88,31 @@ struct tmem_oid {
uint64_t oid[3];
};
struct tmem_xhandle {
uint8_t client_id;
uint8_t xh_data_cksum;
uint16_t xh_data_size;
uint16_t pool_id;
struct tmem_oid oid;
uint32_t index;
void *extra;
};
static inline struct tmem_xhandle tmem_xhandle_fill(uint16_t client_id,
struct tmem_pool *pool,
struct tmem_oid *oidp,
uint32_t index)
{
struct tmem_xhandle xh;
xh.client_id = client_id;
xh.xh_data_cksum = (uint8_t)-1;
xh.xh_data_size = (uint16_t)-1;
xh.pool_id = pool->pool_id;
xh.oid = *oidp;
xh.index = index;
return xh;
}
static inline void tmem_oid_set_invalid(struct tmem_oid *oidp)
{
oidp->oid[0] = oidp->oid[1] = oidp->oid[2] = -1UL;
......@@ -147,7 +171,11 @@ struct tmem_obj {
unsigned int objnode_tree_height;
unsigned long objnode_count;
long pampd_count;
void *extra; /* for private use by pampd implementation */
/* for current design of ramster, all pages belonging to
* an object reside on the same remotenode and extra is
* used to record the number of the remotenode so a
* flush-object operation can specify it */
void *extra; /* for use by pampd implementation */
DECL_SENTINEL
};
......@@ -174,9 +202,14 @@ struct tmem_pamops {
int (*get_data_and_free)(char *, size_t *, bool, void *,
struct tmem_pool *, struct tmem_oid *,
uint32_t);
void (*free)(void *, struct tmem_pool *, struct tmem_oid *, uint32_t);
void (*free)(void *, struct tmem_pool *,
struct tmem_oid *, uint32_t, bool);
void (*free_obj)(struct tmem_pool *, struct tmem_obj *);
bool (*is_remote)(void *);
void *(*repatriate_preload)(void *, struct tmem_pool *,
struct tmem_oid *, uint32_t, bool *);
int (*repatriate)(void *, void *, struct tmem_pool *,
struct tmem_oid *, uint32_t, bool, void *);
void (*new_obj)(struct tmem_obj *);
int (*replace_in_obj)(void *, struct tmem_obj *);
};
......@@ -193,11 +226,16 @@ extern void tmem_register_hostops(struct tmem_hostops *m);
/* core tmem accessor functions */
extern int tmem_put(struct tmem_pool *, struct tmem_oid *, uint32_t index,
char *, size_t, bool, bool);
char *, size_t, bool, int);
extern int tmem_get(struct tmem_pool *, struct tmem_oid *, uint32_t index,
char *, size_t *, bool, int);
extern int tmem_replace(struct tmem_pool *, struct tmem_oid *, uint32_t index,
void *);
extern void *tmem_localify_get_pampd(struct tmem_pool *, struct tmem_oid *,
uint32_t index, struct tmem_obj **,
void **);
extern void tmem_localify_finish(struct tmem_obj *, uint32_t index,
void *, void *, bool);
extern int tmem_flush_page(struct tmem_pool *, struct tmem_oid *,
uint32_t index);
extern int tmem_flush_object(struct tmem_pool *, struct tmem_oid *);
......
drivers/staging/ramster/zcache-main.c
View file @ c89126ea
/*
* zcache.c
*
* Copyright (c) 2010,2011, Dan Magenheimer, Oracle Corp.
* Copyright (c) 2010-2012, Dan Magenheimer, Oracle Corp.
* Copyright (c) 2010,2011, Nitin Gupta
*
* Zcache provides an in-kernel "host implementation" for transcendent memory
......@@ -17,6 +17,9 @@
*
* [1] For a definition of page-accessible memory (aka PAM), see:
* http://marc.info/?l=linux-mm&m=127811271605009
* RAMSTER TODO:
* - handle remotifying of buddied pages (see zbud_remotify_zbpg)
* - kernel boot params: nocleancache/nofrontswap don't always work?!?
*/
#include <linux/module.h>
......@@ -30,11 +33,16 @@
#include <linux/atomic.h>
#include <linux/math64.h>
#include "tmem.h"
#include "zcache.h"
#include "ramster.h"
#include "cluster/tcp.h"
#include "../zram/xvmalloc.h" /* if built in drivers/staging */
#include "xvmalloc.h" /* temporary until change to zsmalloc */
#define RAMSTER_TESTING
#if (!defined(CONFIG_CLEANCACHE) && !defined(CONFIG_FRONTSWAP))
#error "zcache is useless without CONFIG_CLEANCACHE or CONFIG_FRONTSWAP"
#error "ramster is useless without CONFIG_CLEANCACHE or CONFIG_FRONTSWAP"
#endif
#ifdef CONFIG_CLEANCACHE
#include <linux/cleancache.h>
......@@ -43,6 +51,61 @@
#include <linux/frontswap.h>
#endif
enum ramster_remotify_op {
RAMSTER_REMOTIFY_EPH_PUT,
RAMSTER_REMOTIFY_PERS_PUT,
RAMSTER_REMOTIFY_FLUSH_PAGE,
RAMSTER_REMOTIFY_FLUSH_OBJ,
RAMSTER_INTRANSIT_PERS
};
struct ramster_remotify_hdr {
enum ramster_remotify_op op;
struct list_head list;
};
#define ZBH_SENTINEL 0x43214321
#define ZBPG_SENTINEL 0xdeadbeef
#define ZBUD_MAX_BUDS 2
struct zbud_hdr {
struct ramster_remotify_hdr rem_op;
uint16_t client_id;
uint16_t pool_id;
struct tmem_oid oid;
uint32_t index;
uint16_t size; /* compressed size in bytes, zero means unused */
DECL_SENTINEL
};
#define ZVH_SENTINEL 0x43214321
static const int zv_max_page_size = (PAGE_SIZE / 8) * 7;
struct zv_hdr {
struct ramster_remotify_hdr rem_op;
uint16_t client_id;
uint16_t pool_id;
struct tmem_oid oid;
uint32_t index;
DECL_SENTINEL
};
struct flushlist_node {
struct ramster_remotify_hdr rem_op;
struct tmem_xhandle xh;
};
union {
struct ramster_remotify_hdr rem_op;
struct zv_hdr zv;
struct zbud_hdr zbud;
struct flushlist_node flist;
} remotify_list_node;
static LIST_HEAD(zcache_rem_op_list);
static DEFINE_SPINLOCK(zcache_rem_op_list_lock);
#if 0
/* this is more aggressive but may cause other problems? */
#define ZCACHE_GFP_MASK (GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN)
......@@ -98,20 +161,6 @@ static inline bool is_local_client(struct zcache_client *cli)
* read or written unless the zbpg's lock is held.
*/
#define ZBH_SENTINEL 0x43214321
#define ZBPG_SENTINEL 0xdeadbeef
#define ZBUD_MAX_BUDS 2
struct zbud_hdr {
uint16_t client_id;
uint16_t pool_id;
struct tmem_oid oid;
uint32_t index;
uint16_t size; /* compressed size in bytes, zero means unused */
DECL_SENTINEL
};
struct zbud_page {
struct list_head bud_list;
spinlock_t lock;
......@@ -141,20 +190,43 @@ static unsigned long zcache_zbud_buddied_count;
/* protects the buddied list and all unbuddied lists */
static DEFINE_SPINLOCK(zbud_budlists_spinlock);
static LIST_HEAD(zbpg_unused_list);
static unsigned long zcache_zbpg_unused_list_count;
/* protects the unused page list */
static DEFINE_SPINLOCK(zbpg_unused_list_spinlock);
static atomic_t zcache_zbud_curr_raw_pages;
static atomic_t zcache_zbud_curr_zpages;
static unsigned long zcache_zbud_curr_zbytes;
static unsigned long zcache_zbud_cumul_zpages;
static unsigned long zcache_zbud_cumul_zbytes;
static unsigned long zcache_compress_poor;
static unsigned long zcache_policy_percent_exceeded;
static unsigned long zcache_mean_compress_poor;
/*
* RAMster counters
* - Remote pages are pages with a local pampd but the data is remote
* - Foreign pages are pages stored locally but belonging to another node
*/
static atomic_t ramster_remote_pers_pages = ATOMIC_INIT(0);
static unsigned long ramster_pers_remotify_enable;
static unsigned long ramster_eph_remotify_enable;
static unsigned long ramster_eph_pages_remoted;
static unsigned long ramster_eph_pages_remote_failed;
static unsigned long ramster_pers_pages_remoted;
static unsigned long ramster_pers_pages_remote_failed;
static unsigned long ramster_pers_pages_remote_nomem;
static unsigned long ramster_remote_objects_flushed;
static unsigned long ramster_remote_object_flushes_failed;
static unsigned long ramster_remote_pages_flushed;
static unsigned long ramster_remote_page_flushes_failed;
static unsigned long ramster_remote_eph_pages_succ_get;
static unsigned long ramster_remote_pers_pages_succ_get;
static unsigned long ramster_remote_eph_pages_unsucc_get;
static unsigned long ramster_remote_pers_pages_unsucc_get;
static atomic_t ramster_curr_flnode_count = ATOMIC_INIT(0);
static unsigned long ramster_curr_flnode_count_max;
static atomic_t ramster_foreign_eph_pampd_count = ATOMIC_INIT(0);
static unsigned long ramster_foreign_eph_pampd_count_max;
static atomic_t ramster_foreign_pers_pampd_count = ATOMIC_INIT(0);
static unsigned long ramster_foreign_pers_pampd_count_max;
/* forward references */
static void *zcache_get_free_page(void);
static void zcache_free_page(void *p);
......@@ -210,6 +282,29 @@ static char *zbud_data(struct zbud_hdr *zh, unsigned size)
return p;
}
static void zbud_copy_from_pampd(char *data, size_t *size, struct zbud_hdr *zh)
{
struct zbud_page *zbpg;
char *p;
unsigned budnum;
ASSERT_SENTINEL(zh, ZBH);
budnum = zbud_budnum(zh);
zbpg = container_of(zh, struct zbud_page, buddy[budnum]);
spin_lock(&zbpg->lock);
BUG_ON(zh->size > *size);
p = (char *)zbpg;
if (budnum == 0)
p += ((sizeof(struct zbud_page) + CHUNK_SIZE - 1) &
CHUNK_MASK);
else if (budnum == 1)
p += PAGE_SIZE - ((zh->size + CHUNK_SIZE - 1) & CHUNK_MASK);
/* client should be filled in by caller */
memcpy(data, p, zh->size);
*size = zh->size;
spin_unlock(&zbpg->lock);
}
/*
* zbud raw page management
*/
......@@ -218,38 +313,17 @@ static struct zbud_page *zbud_alloc_raw_page(void)
{
struct zbud_page *zbpg = NULL;
struct zbud_hdr *zh0, *zh1;
bool recycled = 0;
/* if any pages on the zbpg list, use one */
spin_lock(&zbpg_unused_list_spinlock);
if (!list_empty(&zbpg_unused_list)) {
zbpg = list_first_entry(&zbpg_unused_list,
struct zbud_page, bud_list);
list_del_init(&zbpg->bud_list);
zcache_zbpg_unused_list_count--;
recycled = 1;
}
spin_unlock(&zbpg_unused_list_spinlock);
if (zbpg == NULL)
/* none on zbpg list, try to get a kernel page */
zbpg = zcache_get_free_page();
if (likely(zbpg != NULL)) {
INIT_LIST_HEAD(&zbpg->bud_list);
zh0 = &zbpg->buddy[0]; zh1 = &zbpg->buddy[1];
spin_lock_init(&zbpg->lock);
if (recycled) {
ASSERT_INVERTED_SENTINEL(zbpg, ZBPG);
SET_SENTINEL(zbpg, ZBPG);
BUG_ON(zh0->size != 0 || tmem_oid_valid(&zh0->oid));
BUG_ON(zh1->size != 0 || tmem_oid_valid(&zh1->oid));
} else {
atomic_inc(&zcache_zbud_curr_raw_pages);
INIT_LIST_HEAD(&zbpg->bud_list);
SET_SENTINEL(zbpg, ZBPG);
zh0->size = 0; zh1->size = 0;
tmem_oid_set_invalid(&zh0->oid);
tmem_oid_set_invalid(&zh1->oid);
}
atomic_inc(&zcache_zbud_curr_raw_pages);
INIT_LIST_HEAD(&zbpg->bud_list);
SET_SENTINEL(zbpg, ZBPG);
zh0->size = 0; zh1->size = 0;
tmem_oid_set_invalid(&zh0->oid);
tmem_oid_set_invalid(&zh1->oid);
}
return zbpg;
}
......@@ -265,10 +339,8 @@ static void zbud_free_raw_page(struct zbud_page *zbpg)
BUG_ON(zh1->size != 0 || tmem_oid_valid(&zh1->oid));
INVERT_SENTINEL(zbpg, ZBPG);
spin_unlock(&zbpg->lock);
spin_lock(&zbpg_unused_list_spinlock);
list_add(&zbpg->bud_list, &zbpg_unused_list);
zcache_zbpg_unused_list_count++;
spin_unlock(&zbpg_unused_list_spinlock);
atomic_dec(&zcache_zbud_curr_raw_pages);
zcache_free_page(zbpg);
}
/*
......@@ -299,6 +371,10 @@ static void zbud_free_and_delist(struct zbud_hdr *zh)
struct zbud_page *zbpg =
container_of(zh, struct zbud_page, buddy[budnum]);
/* FIXME, should be BUG_ON, pool destruction path doesn't disable
* interrupts tmem_destroy_pool()->tmem_pampd_destroy_all_in_obj()->
* tmem_objnode_node_destroy()-> zcache_pampd_free() */
WARN_ON(!irqs_disabled());
spin_lock(&zbpg->lock);
if (list_empty(&zbpg->bud_list)) {
/* ignore zombie page... see zbud_evict_pages() */
......@@ -358,8 +434,8 @@ static struct zbud_hdr *zbud_create(uint16_t client_id, uint16_t pool_id,
if (unlikely(zbpg == NULL))
goto out;
/* ok, have a page, now compress the data before taking locks */
spin_lock(&zbpg->lock);
spin_lock(&zbud_budlists_spinlock);
spin_lock(&zbpg->lock);
list_add_tail(&zbpg->bud_list, &zbud_unbuddied[nchunks].list);
zbud_unbuddied[nchunks].count++;
zh = &zbpg->buddy[0];
......@@ -389,12 +465,10 @@ static struct zbud_hdr *zbud_create(uint16_t client_id, uint16_t pool_id,
zh->oid = *oid;
zh->pool_id = pool_id;
zh->client_id = client_id;
/* can wait to copy the data until the list locks are dropped */
spin_unlock(&zbud_budlists_spinlock);
to = zbud_data(zh, size);
memcpy(to, cdata, size);
spin_unlock(&zbpg->lock);
spin_unlock(&zbud_budlists_spinlock);
zbud_cumul_chunk_counts[nchunks]++;
atomic_inc(&zcache_zbud_curr_zpages);
zcache_zbud_cumul_zpages++;
......@@ -458,9 +532,9 @@ static void zbud_evict_zbpg(struct zbud_page *zbpg)
uint32_t index[ZBUD_MAX_BUDS];
struct tmem_oid oid[ZBUD_MAX_BUDS];
struct tmem_pool *pool;
unsigned long flags;
ASSERT_SPINLOCK(&zbpg->lock);
BUG_ON(!list_empty(&zbpg->bud_list));
for (i = 0, j = 0; i < ZBUD_MAX_BUDS; i++) {
zh = &zbpg->buddy[i];
if (zh->size) {
......@@ -469,20 +543,18 @@ static void zbud_evict_zbpg(struct zbud_page *zbpg)
oid[j] = zh->oid;
index[j] = zh->index;
j++;
zbud_free(zh);
}
}
spin_unlock(&zbpg->lock);
for (i = 0; i < j; i++) {
pool = zcache_get_pool_by_id(client_id[i], pool_id[i]);
if (pool != NULL) {
tmem_flush_page(pool, &oid[i], index[i]);
zcache_put_pool(pool);
}
BUG_ON(pool == NULL);
local_irq_save(flags);
/* these flushes should dispose of any local storage */
tmem_flush_page(pool, &oid[i], index[i]);
local_irq_restore(flags);
zcache_put_pool(pool);
}
ASSERT_SENTINEL(zbpg, ZBPG);
spin_lock(&zbpg->lock);
zbud_free_raw_page(zbpg);
}
/*
......@@ -496,26 +568,8 @@ static void zbud_evict_zbpg(struct zbud_page *zbpg)
static void zbud_evict_pages(int nr)
{
struct zbud_page *zbpg;
int i;
int i, newly_unused_pages = 0;
/* first try freeing any pages on unused list */
retry_unused_list:
spin_lock_bh(&zbpg_unused_list_spinlock);
if (!list_empty(&zbpg_unused_list)) {
/* can't walk list here, since it may change when unlocked */
zbpg = list_first_entry(&zbpg_unused_list,
struct zbud_page, bud_list);
list_del_init(&zbpg->bud_list);
zcache_zbpg_unused_list_count--;
atomic_dec(&zcache_zbud_curr_raw_pages);
spin_unlock_bh(&zbpg_unused_list_spinlock);
zcache_free_page(zbpg);
zcache_evicted_raw_pages++;
if (--nr <= 0)
goto out;
goto retry_unused_list;
}
spin_unlock_bh(&zbpg_unused_list_spinlock);
/* now try freeing unbuddied pages, starting with least space avail */
for (i = 0; i < MAX_CHUNK; i++) {
......@@ -528,15 +582,15 @@ static void zbud_evict_pages(int nr)
list_for_each_entry(zbpg, &zbud_unbuddied[i].list, bud_list) {
if (unlikely(!spin_trylock(&zbpg->lock)))
continue;
list_del_init(&zbpg->bud_list);
zbud_unbuddied[i].count--;
spin_unlock(&zbud_budlists_spinlock);
zcache_evicted_unbuddied_pages++;
/* want budlists unlocked when doing zbpg eviction */
zbud_evict_zbpg(zbpg);
newly_unused_pages++;
local_bh_enable();
if (--nr <= 0)
goto out;
goto evict_unused;
goto retry_unbud_list_i;
}
spin_unlock_bh(&zbud_budlists_spinlock);
......@@ -547,27 +601,413 @@ static void zbud_evict_pages(int nr)
spin_lock_bh(&zbud_budlists_spinlock);
if (list_empty(&zbud_buddied_list)) {
spin_unlock_bh(&zbud_budlists_spinlock);
goto out;
goto evict_unused;
}
list_for_each_entry(zbpg, &zbud_buddied_list, bud_list) {
if (unlikely(!spin_trylock(&zbpg->lock)))
continue;
list_del_init(&zbpg->bud_list);
zcache_zbud_buddied_count--;
spin_unlock(&zbud_budlists_spinlock);
zcache_evicted_buddied_pages++;
/* want budlists unlocked when doing zbpg eviction */
zbud_evict_zbpg(zbpg);
newly_unused_pages++;
local_bh_enable();
if (--nr <= 0)
goto out;
goto evict_unused;
goto retry_bud_list;
}
spin_unlock_bh(&zbud_budlists_spinlock);
evict_unused:
return;
}
static DEFINE_PER_CPU(unsigned char *, zcache_remoteputmem);
static int zbud_remotify_zbud(struct tmem_xhandle *xh, char *data,
size_t size)
{
struct tmem_pool *pool;
int i, remotenode, ret = -1;
unsigned char cksum, *p;
unsigned long flags;
for (p = data, cksum = 0, i = 0; i < size; i++)
cksum += *p;
ret = ramster_remote_put(xh, data, size, true, &remotenode);
if (ret == 0) {
/* data was successfully remoted so change the local version
* to point to the remote node where it landed */
pool = zcache_get_pool_by_id(LOCAL_CLIENT, xh->pool_id);
BUG_ON(pool == NULL);
local_irq_save(flags);
/* tmem_replace will also free up any local space */
(void)tmem_replace(pool, &xh->oid, xh->index,
pampd_make_remote(remotenode, size, cksum));
local_irq_restore(flags);
zcache_put_pool(pool);
ramster_eph_pages_remoted++;
ret = 0;
} else
ramster_eph_pages_remote_failed++;
return ret;
}
static int zbud_remotify_zbpg(struct zbud_page *zbpg)
{
struct zbud_hdr *zh1, *zh2 = NULL;
struct tmem_xhandle xh1, xh2 = { 0 };
char *data1 = NULL, *data2 = NULL;
size_t size1 = 0, size2 = 0;
int ret = 0;
unsigned char *tmpmem = __get_cpu_var(zcache_remoteputmem);
ASSERT_SPINLOCK(&zbpg->lock);
if (zbpg->buddy[0].size == 0)
zh1 = &zbpg->buddy[1];
else if (zbpg->buddy[1].size == 0)
zh1 = &zbpg->buddy[0];
else {
zh1 = &zbpg->buddy[0];
zh2 = &zbpg->buddy[1];
}
/* don't remotify pages that are already remotified */
if (zh1->client_id != LOCAL_CLIENT)
zh1 = NULL;
if ((zh2 != NULL) && (zh2->client_id != LOCAL_CLIENT))
zh2 = NULL;
/* copy the data and metadata so can release lock */
if (zh1 != NULL) {
xh1.client_id = zh1->client_id;
xh1.pool_id = zh1->pool_id;
xh1.oid = zh1->oid;
xh1.index = zh1->index;
size1 = zh1->size;
data1 = zbud_data(zh1, size1);
memcpy(tmpmem, zbud_data(zh1, size1), size1);
data1 = tmpmem;
tmpmem += size1;
}
if (zh2 != NULL) {
xh2.client_id = zh2->client_id;
xh2.pool_id = zh2->pool_id;
xh2.oid = zh2->oid;
xh2.index = zh2->index;
size2 = zh2->size;
memcpy(tmpmem, zbud_data(zh2, size2), size2);
data2 = tmpmem;
}
spin_unlock(&zbpg->lock);
preempt_enable();
/* OK, no locks held anymore, remotify one or both zbuds */
if (zh1 != NULL)
ret = zbud_remotify_zbud(&xh1, data1, size1);
if (zh2 != NULL)
ret |= zbud_remotify_zbud(&xh2, data2, size2);
return ret;
}
void zbud_remotify_pages(int nr)
{
struct zbud_page *zbpg;
int i, ret;
/*
* for now just try remotifying unbuddied pages, starting with
* least space avail
*/
for (i = 0; i < MAX_CHUNK; i++) {
retry_unbud_list_i:
preempt_disable(); /* enable in zbud_remotify_zbpg */
spin_lock_bh(&zbud_budlists_spinlock);
if (list_empty(&zbud_unbuddied[i].list)) {
spin_unlock_bh(&zbud_budlists_spinlock);
preempt_enable();
continue; /* next i in for loop */
}
list_for_each_entry(zbpg, &zbud_unbuddied[i].list, bud_list) {
if (unlikely(!spin_trylock(&zbpg->lock)))
continue; /* next list_for_each_entry */
zbud_unbuddied[i].count--;
/* want budlists unlocked when doing zbpg remotify */
spin_unlock_bh(&zbud_budlists_spinlock);
ret = zbud_remotify_zbpg(zbpg);
/* preemption is re-enabled in zbud_remotify_zbpg */
if (ret == 0) {
if (--nr <= 0)
goto out;
goto retry_unbud_list_i;
}
/* if fail to remotify any page, quit */
pr_err("TESTING zbud_remotify_pages failed on page,"
" trying to re-add\n");
spin_lock_bh(&zbud_budlists_spinlock);
spin_lock(&zbpg->lock);
list_add_tail(&zbpg->bud_list, &zbud_unbuddied[i].list);
zbud_unbuddied[i].count++;
spin_unlock(&zbpg->lock);
spin_unlock_bh(&zbud_budlists_spinlock);
pr_err("TESTING zbud_remotify_pages failed on page,"
" finished re-add\n");
goto out;
}
spin_unlock_bh(&zbud_budlists_spinlock);
preempt_enable();
}
next_buddied_zbpg:
preempt_disable(); /* enable in zbud_remotify_zbpg */
spin_lock_bh(&zbud_budlists_spinlock);
if (list_empty(&zbud_buddied_list))
goto unlock_out;
list_for_each_entry(zbpg, &zbud_buddied_list, bud_list) {
if (unlikely(!spin_trylock(&zbpg->lock)))
continue; /* next list_for_each_entry */
zcache_zbud_buddied_count--;
/* want budlists unlocked when doing zbpg remotify */
spin_unlock_bh(&zbud_budlists_spinlock);
ret = zbud_remotify_zbpg(zbpg);
/* preemption is re-enabled in zbud_remotify_zbpg */
if (ret == 0) {
if (--nr <= 0)
goto out;
goto next_buddied_zbpg;
}
/* if fail to remotify any page, quit */
pr_err("TESTING zbud_remotify_pages failed on BUDDIED page,"
" trying to re-add\n");
spin_lock_bh(&zbud_budlists_spinlock);
spin_lock(&zbpg->lock);
list_add_tail(&zbpg->bud_list, &zbud_buddied_list);
zcache_zbud_buddied_count++;
spin_unlock(&zbpg->lock);
spin_unlock_bh(&zbud_budlists_spinlock);
pr_err("TESTING zbud_remotify_pages failed on BUDDIED page,"
" finished re-add\n");
goto out;
}
unlock_out:
spin_unlock_bh(&zbud_budlists_spinlock);
preempt_enable();
out:
return;
}
/* the "flush list" asynchronously collects pages to remotely flush */
#define FLUSH_ENTIRE_OBJECT ((uint32_t)-1)
static void ramster_flnode_free(struct flushlist_node *,
struct tmem_pool *);
static void zcache_remote_flush_page(struct flushlist_node *flnode)
{
struct tmem_xhandle *xh;
int remotenode, ret;
preempt_disable();
xh = &flnode->xh;
remotenode = flnode->xh.client_id;
ret = ramster_remote_flush(xh, remotenode);
if (ret >= 0)
ramster_remote_pages_flushed++;
else
ramster_remote_page_flushes_failed++;
preempt_enable_no_resched();
ramster_flnode_free(flnode, NULL);
}
static void zcache_remote_flush_object(struct flushlist_node *flnode)
{
struct tmem_xhandle *xh;
int remotenode, ret;
preempt_disable();
xh = &flnode->xh;
remotenode = flnode->xh.client_id;
ret = ramster_remote_flush_object(xh, remotenode);
if (ret >= 0)
ramster_remote_objects_flushed++;
else
ramster_remote_object_flushes_failed++;
preempt_enable_no_resched();
ramster_flnode_free(flnode, NULL);
}
static void zcache_remote_eph_put(struct zbud_hdr *zbud)
{
/* FIXME */
}
static void zcache_remote_pers_put(struct zv_hdr *zv)
{
struct tmem_xhandle xh;
uint16_t size;
bool ephemeral;
int remotenode, ret = -1;
char *data;
struct tmem_pool *pool;
unsigned long flags;
unsigned char cksum;
char *p;
int i;
unsigned char *tmpmem = __get_cpu_var(zcache_remoteputmem);
ASSERT_SENTINEL(zv, ZVH);
BUG_ON(zv->client_id != LOCAL_CLIENT);
local_bh_disable();
xh.client_id = zv->client_id;
xh.pool_id = zv->pool_id;
xh.oid = zv->oid;
xh.index = zv->index;
size = xv_get_object_size(zv) - sizeof(*zv);
BUG_ON(size == 0 || size > zv_max_page_size);
data = (char *)zv + sizeof(*zv);
for (p = data, cksum = 0, i = 0; i < size; i++)
cksum += *p;
memcpy(tmpmem, data, size);
data = tmpmem;
pool = zcache_get_pool_by_id(zv->client_id, zv->pool_id);
ephemeral = is_ephemeral(pool);
zcache_put_pool(pool);
/* now OK to release lock set in caller */
spin_unlock(&zcache_rem_op_list_lock);
local_bh_enable();
preempt_disable();
ret = ramster_remote_put(&xh, data, size, ephemeral, &remotenode);
preempt_enable_no_resched();
if (ret != 0) {
/*
* This is some form of a memory leak... if the remote put
* fails, there will never be another attempt to remotify
* this page. But since we've dropped the zv pointer,
* the page may have been freed or the data replaced
* so we can't just "put it back" in the remote op list.
* Even if we could, not sure where to put it in the list
* because there may be flushes that must be strictly
* ordered vs the put. So leave this as a FIXME for now.
* But count them so we know if it becomes a problem.
*/
ramster_pers_pages_remote_failed++;
goto out;
} else
atomic_inc(&ramster_remote_pers_pages);
ramster_pers_pages_remoted++;
/*
* data was successfully remoted so change the local version to
* point to the remote node where it landed
*/
local_bh_disable();
pool = zcache_get_pool_by_id(LOCAL_CLIENT, xh.pool_id);
local_irq_save(flags);
(void)tmem_replace(pool, &xh.oid, xh.index,
pampd_make_remote(remotenode, size, cksum));
local_irq_restore(flags);
zcache_put_pool(pool);
local_bh_enable();
out:
return;
}
static void zcache_do_remotify_ops(int nr)
{
struct ramster_remotify_hdr *rem_op;
union remotify_list_node *u;
while (1) {
if (!nr)
goto out;
spin_lock(&zcache_rem_op_list_lock);
if (list_empty(&zcache_rem_op_list)) {
spin_unlock(&zcache_rem_op_list_lock);
goto out;
}
rem_op = list_first_entry(&zcache_rem_op_list,
struct ramster_remotify_hdr, list);
list_del_init(&rem_op->list);
if (rem_op->op != RAMSTER_REMOTIFY_PERS_PUT)
spin_unlock(&zcache_rem_op_list_lock);
u = (union remotify_list_node *)rem_op;
switch (rem_op->op) {
case RAMSTER_REMOTIFY_EPH_PUT:
BUG();
zcache_remote_eph_put((struct zbud_hdr *)rem_op);
break;
case RAMSTER_REMOTIFY_PERS_PUT:
zcache_remote_pers_put((struct zv_hdr *)rem_op);
break;
case RAMSTER_REMOTIFY_FLUSH_PAGE:
zcache_remote_flush_page((struct flushlist_node *)u);
break;
case RAMSTER_REMOTIFY_FLUSH_OBJ:
zcache_remote_flush_object((struct flushlist_node *)u);
break;
default:
BUG();
}
}
out:
return;
}
/*
* Communicate interface revision with userspace
*/
#include "cluster/ramster_nodemanager.h"
static unsigned long ramster_interface_revision = R2NM_API_VERSION;
/*
* For now, just push over a few pages every few seconds to
* ensure that it basically works
*/
static struct workqueue_struct *ramster_remotify_workqueue;
static void ramster_remotify_process(struct work_struct *work);
static DECLARE_DELAYED_WORK(ramster_remotify_worker,
ramster_remotify_process);
static void ramster_remotify_queue_delayed_work(unsigned long delay)
{
if (!queue_delayed_work(ramster_remotify_workqueue,
&ramster_remotify_worker, delay))
pr_err("ramster_remotify: bad workqueue\n");
}
static int use_frontswap;
static int use_cleancache;
static int ramster_remote_target_nodenum = -1;
static void ramster_remotify_process(struct work_struct *work)
{
static bool remotify_in_progress;
BUG_ON(irqs_disabled());
if (remotify_in_progress)
ramster_remotify_queue_delayed_work(HZ);
else if (ramster_remote_target_nodenum != -1) {
remotify_in_progress = true;
#ifdef CONFIG_CLEANCACHE
if (use_cleancache && ramster_eph_remotify_enable)
zbud_remotify_pages(5000); /* FIXME is this a good number? */
#endif
#ifdef CONFIG_FRONTSWAP
if (use_frontswap && ramster_pers_remotify_enable)
zcache_do_remotify_ops(500); /* FIXME is this a good number? */
#endif
remotify_in_progress = false;
ramster_remotify_queue_delayed_work(HZ);
}
}
static void ramster_remotify_init(void)
{
unsigned long n = 60UL;
ramster_remotify_workqueue =
create_singlethread_workqueue("ramster_remotify");
ramster_remotify_queue_delayed_work(n * HZ);
}
static void zbud_init(void)
{
int i;
......@@ -631,15 +1071,6 @@ static int zbud_show_cumul_chunk_counts(char *buf)
* necessary for decompression) immediately preceding the compressed data.
*/
#define ZVH_SENTINEL 0x43214321
struct zv_hdr {
uint32_t pool_id;
struct tmem_oid oid;
uint32_t index;
DECL_SENTINEL
};
/* rudimentary policy limits */
/* total number of persistent pages may not exceed this percentage */
static unsigned int zv_page_count_policy_percent = 75;
......@@ -655,10 +1086,11 @@ static unsigned int zv_max_zsize = (PAGE_SIZE / 8) * 7;
*/
static unsigned int zv_max_mean_zsize = (PAGE_SIZE / 8) * 5;
static unsigned long zv_curr_dist_counts[NCHUNKS];
static unsigned long zv_cumul_dist_counts[NCHUNKS];
static atomic_t zv_curr_dist_counts[NCHUNKS];
static atomic_t zv_cumul_dist_counts[NCHUNKS];
static struct zv_hdr *zv_create(struct xv_pool *xvpool, uint32_t pool_id,
static struct zv_hdr *zv_create(struct zcache_client *cli, uint32_t pool_id,
struct tmem_oid *oid, uint32_t index,
void *cdata, unsigned clen)
{
......@@ -671,23 +1103,61 @@ static struct zv_hdr *zv_create(struct xv_pool *xvpool, uint32_t pool_id,
BUG_ON(!irqs_disabled());
BUG_ON(chunks >= NCHUNKS);
ret = xv_malloc(xvpool, alloc_size,
ret = xv_malloc(cli->xvpool, clen + sizeof(struct zv_hdr),
&page, &offset, ZCACHE_GFP_MASK);
if (unlikely(ret))
goto out;
zv_curr_dist_counts[chunks]++;
zv_cumul_dist_counts[chunks]++;
atomic_inc(&zv_curr_dist_counts[chunks]);
atomic_inc(&zv_cumul_dist_counts[chunks]);
zv = kmap_atomic(page, KM_USER0) + offset;
zv->index = index;
zv->oid = *oid;
zv->pool_id = pool_id;
SET_SENTINEL(zv, ZVH);
INIT_LIST_HEAD(&zv->rem_op.list);
zv->client_id = get_client_id_from_client(cli);
zv->rem_op.op = RAMSTER_REMOTIFY_PERS_PUT;
if (zv->client_id == LOCAL_CLIENT) {
spin_lock(&zcache_rem_op_list_lock);
list_add_tail(&zv->rem_op.list, &zcache_rem_op_list);
spin_unlock(&zcache_rem_op_list_lock);
}
memcpy((char *)zv + sizeof(struct zv_hdr), cdata, clen);
kunmap_atomic(zv, KM_USER0);
out:
return zv;
}
/* similar to zv_create, but just reserve space, no data yet */
static struct zv_hdr *zv_alloc(struct tmem_pool *pool,
struct tmem_oid *oid, uint32_t index,
unsigned clen)
{
struct zcache_client *cli = pool->client;
struct page *page;
struct zv_hdr *zv = NULL;
uint32_t offset;
int ret;
BUG_ON(!irqs_disabled());
BUG_ON(!is_local_client(pool->client));
ret = xv_malloc(cli->xvpool, clen + sizeof(struct zv_hdr),
&page, &offset, ZCACHE_GFP_MASK);
if (unlikely(ret))
goto out;
zv = kmap_atomic(page, KM_USER0) + offset;
SET_SENTINEL(zv, ZVH);
INIT_LIST_HEAD(&zv->rem_op.list);
zv->client_id = LOCAL_CLIENT;
zv->rem_op.op = RAMSTER_INTRANSIT_PERS;
zv->index = index;
zv->oid = *oid;
zv->pool_id = pool->pool_id;
kunmap_atomic(zv, KM_USER0);
out:
return zv;
}
static void zv_free(struct xv_pool *xvpool, struct zv_hdr *zv)
{
unsigned long flags;
......@@ -698,10 +1168,15 @@ static void zv_free(struct xv_pool *xvpool, struct zv_hdr *zv)
ASSERT_SENTINEL(zv, ZVH);
BUG_ON(chunks >= NCHUNKS);
zv_curr_dist_counts[chunks]--;
atomic_dec(&zv_curr_dist_counts[chunks]);
size -= sizeof(*zv);
spin_lock(&zcache_rem_op_list_lock);
size = xv_get_object_size(zv) - sizeof(*zv);
BUG_ON(size == 0);
INVERT_SENTINEL(zv, ZVH);
if (!list_empty(&zv->rem_op.list))
list_del_init(&zv->rem_op.list);
spin_unlock(&zcache_rem_op_list_lock);
page = virt_to_page(zv);
offset = (unsigned long)zv & ~PAGE_MASK;
local_irq_save(flags);
......@@ -727,6 +1202,29 @@ static void zv_decompress(struct page *page, struct zv_hdr *zv)
BUG_ON(clen != PAGE_SIZE);
}
static void zv_copy_from_pampd(char *data, size_t *bufsize, struct zv_hdr *zv)
{
unsigned size;
ASSERT_SENTINEL(zv, ZVH);
size = xv_get_object_size(zv) - sizeof(*zv);
BUG_ON(size == 0 || size > zv_max_page_size);
BUG_ON(size > *bufsize);
memcpy(data, (char *)zv + sizeof(*zv), size);
*bufsize = size;
}
static void zv_copy_to_pampd(struct zv_hdr *zv, char *data, size_t size)
{
unsigned zv_size;
ASSERT_SENTINEL(zv, ZVH);
zv_size = xv_get_object_size(zv) - sizeof(*zv);
BUG_ON(zv_size != size);
BUG_ON(zv_size == 0 || zv_size > zv_max_page_size);
memcpy((char *)zv + sizeof(*zv), data, size);
}
#ifdef CONFIG_SYSFS
/*
* show a distribution of compression stats for zv pages.
......@@ -738,7 +1236,7 @@ static int zv_curr_dist_counts_show(char *buf)
char *p = buf;
for (i = 0; i < NCHUNKS; i++) {
n = zv_curr_dist_counts[i];
n = atomic_read(&zv_curr_dist_counts[i]);
p += sprintf(p, "%lu ", n);
chunks += n;
sum_total_chunks += i * n;
......@@ -754,7 +1252,7 @@ static int zv_cumul_dist_counts_show(char *buf)
char *p = buf;
for (i = 0; i < NCHUNKS; i++) {
n = zv_cumul_dist_counts[i];
n = atomic_read(&zv_cumul_dist_counts[i]);
p += sprintf(p, "%lu ", n);
chunks += n;
sum_total_chunks += i * n;
......@@ -787,7 +1285,7 @@ static ssize_t zv_max_zsize_store(struct kobject *kobj,
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
err = strict_strtoul(buf, 10, &val);
err = kstrtoul(buf, 10, &val);
if (err || (val == 0) || (val > (PAGE_SIZE / 8) * 7))
return -EINVAL;
zv_max_zsize = val;
......@@ -819,7 +1317,7 @@ static ssize_t zv_max_mean_zsize_store(struct kobject *kobj,
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
err = strict_strtoul(buf, 10, &val);
err = kstrtoul(buf, 10, &val);
if (err || (val == 0) || (val > (PAGE_SIZE / 8) * 7))
return -EINVAL;
zv_max_mean_zsize = val;
......@@ -853,7 +1351,7 @@ static ssize_t zv_page_count_policy_percent_store(struct kobject *kobj,
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
err = strict_strtoul(buf, 10, &val);
err = kstrtoul(buf, 10, &val);
if (err || (val == 0) || (val > 150))
return -EINVAL;
zv_page_count_policy_percent = val;
......@@ -890,6 +1388,7 @@ static unsigned long zcache_flush_found;
static unsigned long zcache_flobj_total;
static unsigned long zcache_flobj_found;
static unsigned long zcache_failed_eph_puts;
static unsigned long zcache_nonactive_puts;
static unsigned long zcache_failed_pers_puts;
/*
......@@ -970,6 +1469,7 @@ static unsigned long zcache_put_to_flush;
*/
static struct kmem_cache *zcache_objnode_cache;
static struct kmem_cache *zcache_obj_cache;
static struct kmem_cache *ramster_flnode_cache;
static atomic_t zcache_curr_obj_count = ATOMIC_INIT(0);
static unsigned long zcache_curr_obj_count_max;
static atomic_t zcache_curr_objnode_count = ATOMIC_INIT(0);
......@@ -985,6 +1485,7 @@ struct zcache_preload {
struct tmem_obj *obj;
int nr;
struct tmem_objnode *objnodes[OBJNODE_TREE_MAX_PATH];
struct flushlist_node *flnode;
};
static DEFINE_PER_CPU(struct zcache_preload, zcache_preloads) = { 0, };
......@@ -993,6 +1494,7 @@ static int zcache_do_preload(struct tmem_pool *pool)
struct zcache_preload *kp;
struct tmem_objnode *objnode;
struct tmem_obj *obj;
struct flushlist_node *flnode;
void *page;
int ret = -ENOMEM;
......@@ -1023,27 +1525,61 @@ static int zcache_do_preload(struct tmem_pool *pool)
zcache_failed_alloc++;
goto out;
}
page = (void *)__get_free_page(ZCACHE_GFP_MASK);
if (unlikely(page == NULL)) {
zcache_failed_get_free_pages++;
kmem_cache_free(zcache_obj_cache, obj);
flnode = kmem_cache_alloc(ramster_flnode_cache, ZCACHE_GFP_MASK);
if (unlikely(flnode == NULL)) {
zcache_failed_alloc++;
goto out;
}
if (is_ephemeral(pool)) {
page = (void *)__get_free_page(ZCACHE_GFP_MASK);
if (unlikely(page == NULL)) {
zcache_failed_get_free_pages++;
kmem_cache_free(zcache_obj_cache, obj);
kmem_cache_free(ramster_flnode_cache, flnode);
goto out;
}
}
preempt_disable();
kp = &__get_cpu_var(zcache_preloads);
if (kp->obj == NULL)
kp->obj = obj;
else
kmem_cache_free(zcache_obj_cache, obj);
if (kp->page == NULL)
kp->page = page;
if (kp->flnode == NULL)
kp->flnode = flnode;
else
free_page((unsigned long)page);
kmem_cache_free(ramster_flnode_cache, flnode);
if (is_ephemeral(pool)) {
if (kp->page == NULL)
kp->page = page;
else
free_page((unsigned long)page);
}
ret = 0;
out:
return ret;
}
static int ramster_do_preload_flnode_only(struct tmem_pool *pool)
{
struct zcache_preload *kp;
struct flushlist_node *flnode;
int ret = -ENOMEM;
BUG_ON(!irqs_disabled());
if (unlikely(ramster_flnode_cache == NULL))
BUG();
kp = &__get_cpu_var(zcache_preloads);
flnode = kmem_cache_alloc(ramster_flnode_cache, GFP_ATOMIC);
if (unlikely(flnode == NULL) && kp->flnode == NULL)
BUG(); /* FIXME handle more gracefully, but how??? */
else if (kp->flnode == NULL)
kp->flnode = flnode;
else
kmem_cache_free(ramster_flnode_cache, flnode);
return ret;
}
static void *zcache_get_free_page(void)
{
struct zcache_preload *kp;
......@@ -1116,6 +1652,30 @@ static void zcache_obj_free(struct tmem_obj *obj, struct tmem_pool *pool)
kmem_cache_free(zcache_obj_cache, obj);
}
static struct flushlist_node *ramster_flnode_alloc(struct tmem_pool *pool)
{
struct flushlist_node *flnode = NULL;
struct zcache_preload *kp;
int count;
kp = &__get_cpu_var(zcache_preloads);
flnode = kp->flnode;
BUG_ON(flnode == NULL);
kp->flnode = NULL;
count = atomic_inc_return(&ramster_curr_flnode_count);
if (count > ramster_curr_flnode_count_max)
ramster_curr_flnode_count_max = count;
return flnode;
}
static void ramster_flnode_free(struct flushlist_node *flnode,
struct tmem_pool *pool)
{
atomic_dec(&ramster_curr_flnode_count);
BUG_ON(atomic_read(&ramster_curr_flnode_count) < 0);
kmem_cache_free(ramster_flnode_cache, flnode);
}
static struct tmem_hostops zcache_hostops = {
.obj_alloc = zcache_obj_alloc,
.obj_free = zcache_obj_free,
......@@ -1127,6 +1687,14 @@ static struct tmem_hostops zcache_hostops = {
* zcache implementations for PAM page descriptor ops
*/
static inline void dec_and_check(atomic_t *pvar)
{
atomic_dec(pvar);
/* later when all accounting is fixed, make this a BUG */
WARN_ON_ONCE(atomic_read(pvar) < 0);
}
static atomic_t zcache_curr_eph_pampd_count = ATOMIC_INIT(0);
static unsigned long zcache_curr_eph_pampd_count_max;
static atomic_t zcache_curr_pers_pampd_count = ATOMIC_INIT(0);
......@@ -1135,22 +1703,20 @@ static unsigned long zcache_curr_pers_pampd_count_max;
/* forward reference */
static int zcache_compress(struct page *from, void **out_va, size_t *out_len);
static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
static int zcache_pampd_eph_create(char *data, size_t size, bool raw,
struct tmem_pool *pool, struct tmem_oid *oid,
uint32_t index)
uint32_t index, void **pampd)
{
void *pampd = NULL, *cdata;
size_t clen;
int ret;
unsigned long count;
struct page *page = (struct page *)(data);
int ret = -1;
void *cdata = data;
size_t clen = size;
struct zcache_client *cli = pool->client;
uint16_t client_id = get_client_id_from_client(cli);
unsigned long zv_mean_zsize;
unsigned long curr_pers_pampd_count;
u64 total_zsize;
struct page *page = NULL;
unsigned long count;
if (eph) {
if (!raw) {
page = virt_to_page(data);
ret = zcache_compress(page, &cdata, &clen);
if (ret == 0)
goto out;
......@@ -1158,46 +1724,114 @@ static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
zcache_compress_poor++;
goto out;
}
pampd = (void *)zbud_create(client_id, pool->pool_id, oid,
index, page, cdata, clen);
if (pampd != NULL) {
count = atomic_inc_return(&zcache_curr_eph_pampd_count);
if (count > zcache_curr_eph_pampd_count_max)
zcache_curr_eph_pampd_count_max = count;
}
} else {
curr_pers_pampd_count =
atomic_read(&zcache_curr_pers_pampd_count);
if (curr_pers_pampd_count >
(zv_page_count_policy_percent * totalram_pages) / 100)
goto out;
ret = zcache_compress(page, &cdata, &clen);
if (ret == 0)
goto out;
/* reject if compression is too poor */
if (clen > zv_max_zsize) {
zcache_compress_poor++;
}
*pampd = (void *)zbud_create(client_id, pool->pool_id, oid,
index, page, cdata, clen);
if (*pampd == NULL) {
ret = -ENOMEM;
goto out;
}
ret = 0;
count = atomic_inc_return(&zcache_curr_eph_pampd_count);
if (count > zcache_curr_eph_pampd_count_max)
zcache_curr_eph_pampd_count_max = count;
if (client_id != LOCAL_CLIENT) {
count = atomic_inc_return(&ramster_foreign_eph_pampd_count);
if (count > ramster_foreign_eph_pampd_count_max)
ramster_foreign_eph_pampd_count_max = count;
}
out:
return ret;
}
static int zcache_pampd_pers_create(char *data, size_t size, bool raw,
struct tmem_pool *pool, struct tmem_oid *oid,
uint32_t index, void **pampd)
{
int ret = -1;
void *cdata = data;
size_t clen = size;
struct zcache_client *cli = pool->client;
struct page *page;
unsigned long count;
unsigned long zv_mean_zsize;
struct zv_hdr *zv;
long curr_pers_pampd_count;
u64 total_zsize;
#ifdef RAMSTER_TESTING
static bool pampd_neg_warned;
#endif
curr_pers_pampd_count = atomic_read(&zcache_curr_pers_pampd_count) -
atomic_read(&ramster_remote_pers_pages);
#ifdef RAMSTER_TESTING
/* should always be positive, but warn if accounting is off */
if (!pampd_neg_warned) {
pr_warn("ramster: bad accounting for curr_pers_pampd_count\n");
pampd_neg_warned = true;
}
#endif
if (curr_pers_pampd_count >
(zv_page_count_policy_percent * totalram_pages) / 100) {
zcache_policy_percent_exceeded++;
goto out;
}
if (raw)
goto ok_to_create;
page = virt_to_page(data);
if (zcache_compress(page, &cdata, &clen) == 0)
goto out;
/* reject if compression is too poor */
if (clen > zv_max_zsize) {
zcache_compress_poor++;
goto out;
}
/* reject if mean compression is too poor */
if ((clen > zv_max_mean_zsize) && (curr_pers_pampd_count > 0)) {
total_zsize = xv_get_total_size_bytes(cli->xvpool);
zv_mean_zsize = div_u64(total_zsize, curr_pers_pampd_count);
if (zv_mean_zsize > zv_max_mean_zsize) {
zcache_mean_compress_poor++;
goto out;
}
/* reject if mean compression is too poor */
if ((clen > zv_max_mean_zsize) && (curr_pers_pampd_count > 0)) {
total_zsize = xv_get_total_size_bytes(cli->xvpool);
zv_mean_zsize = div_u64(total_zsize,
curr_pers_pampd_count);
if (zv_mean_zsize > zv_max_mean_zsize) {
zcache_mean_compress_poor++;
goto out;
}
}
pampd = (void *)zv_create(cli->xvpool, pool->pool_id,
oid, index, cdata, clen);
if (pampd == NULL)
goto out;
count = atomic_inc_return(&zcache_curr_pers_pampd_count);
if (count > zcache_curr_pers_pampd_count_max)
zcache_curr_pers_pampd_count_max = count;
}
ok_to_create:
*pampd = (void *)zv_create(cli, pool->pool_id, oid, index, cdata, clen);
if (*pampd == NULL) {
ret = -ENOMEM;
goto out;
}
ret = 0;
count = atomic_inc_return(&zcache_curr_pers_pampd_count);
if (count > zcache_curr_pers_pampd_count_max)
zcache_curr_pers_pampd_count_max = count;
if (is_local_client(cli))
goto out;
zv = *(struct zv_hdr **)pampd;
count = atomic_inc_return(&ramster_foreign_pers_pampd_count);
if (count > ramster_foreign_pers_pampd_count_max)
ramster_foreign_pers_pampd_count_max = count;
out:
return ret;
}
static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
struct tmem_pool *pool, struct tmem_oid *oid,
uint32_t index)
{
void *pampd = NULL;
int ret;
bool ephemeral;
BUG_ON(preemptible());
ephemeral = (eph == 1) || ((eph == 0) && is_ephemeral(pool));
if (ephemeral)
ret = zcache_pampd_eph_create(data, size, raw, pool,
oid, index, &pampd);
else
ret = zcache_pampd_pers_create(data, size, raw, pool,
oid, index, &pampd);
/* FIXME add some counters here for failed creates? */
return pampd;
}
......@@ -1211,75 +1845,343 @@ static int zcache_pampd_get_data(char *data, size_t *bufsize, bool raw,
{
int ret = 0;
BUG_ON(is_ephemeral(pool));
zv_decompress((struct page *)(data), pampd);
return ret;
}
/*
* fill the pageframe corresponding to the struct page with the data
* from the passed pampd
*/
BUG_ON(preemptible());
BUG_ON(is_ephemeral(pool)); /* Fix later for shared pools? */
BUG_ON(pampd_is_remote(pampd));
if (raw)
zv_copy_from_pampd(data, bufsize, pampd);
else
zv_decompress(virt_to_page(data), pampd);
return ret;
}
static int zcache_pampd_get_data_and_free(char *data, size_t *bufsize, bool raw,
void *pampd, struct tmem_pool *pool,
struct tmem_oid *oid, uint32_t index)
{
int ret = 0;
unsigned long flags;
struct zcache_client *cli = pool->client;
BUG_ON(!is_ephemeral(pool));
zbud_decompress((struct page *)(data), pampd);
zbud_free_and_delist((struct zbud_hdr *)pampd);
atomic_dec(&zcache_curr_eph_pampd_count);
BUG_ON(preemptible());
BUG_ON(pampd_is_remote(pampd));
if (is_ephemeral(pool)) {
local_irq_save(flags);
if (raw)
zbud_copy_from_pampd(data, bufsize, pampd);
else
ret = zbud_decompress(virt_to_page(data), pampd);
zbud_free_and_delist((struct zbud_hdr *)pampd);
local_irq_restore(flags);
if (!is_local_client(cli))
dec_and_check(&ramster_foreign_eph_pampd_count);
dec_and_check(&zcache_curr_eph_pampd_count);
} else {
if (is_local_client(cli))
BUG();
if (raw)
zv_copy_from_pampd(data, bufsize, pampd);
else
zv_decompress(virt_to_page(data), pampd);
zv_free(cli->xvpool, pampd);
if (!is_local_client(cli))
dec_and_check(&ramster_foreign_pers_pampd_count);
dec_and_check(&zcache_curr_pers_pampd_count);
ret = 0;
}
return ret;
}
static bool zcache_pampd_is_remote(void *pampd)
{
return pampd_is_remote(pampd);
}
/*
* free the pampd and remove it from any zcache lists
* pampd must no longer be pointed to from any tmem data structures!
*/
static void zcache_pampd_free(void *pampd, struct tmem_pool *pool,
struct tmem_oid *oid, uint32_t index)
struct tmem_oid *oid, uint32_t index, bool acct)
{
struct zcache_client *cli = pool->client;
if (is_ephemeral(pool)) {
bool eph = is_ephemeral(pool);
struct zv_hdr *zv;
BUG_ON(preemptible());
if (pampd_is_remote(pampd)) {
WARN_ON(acct == false);
if (oid == NULL) {
/*
* a NULL oid means to ignore this pampd free
* as the remote freeing will be handled elsewhere
*/
} else if (eph) {
/* FIXME remote flush optional but probably good idea */
/* FIXME get these working properly again */
dec_and_check(&zcache_curr_eph_pampd_count);
} else if (pampd_is_intransit(pampd)) {
/* did a pers remote get_and_free, so just free local */
pampd = pampd_mask_intransit_and_remote(pampd);
goto local_pers;
} else {
struct flushlist_node *flnode =
ramster_flnode_alloc(pool);
flnode->xh.client_id = pampd_remote_node(pampd);
flnode->xh.pool_id = pool->pool_id;
flnode->xh.oid = *oid;
flnode->xh.index = index;
flnode->rem_op.op = RAMSTER_REMOTIFY_FLUSH_PAGE;
spin_lock(&zcache_rem_op_list_lock);
list_add(&flnode->rem_op.list, &zcache_rem_op_list);
spin_unlock(&zcache_rem_op_list_lock);
dec_and_check(&zcache_curr_pers_pampd_count);
dec_and_check(&ramster_remote_pers_pages);
}
} else if (eph) {
zbud_free_and_delist((struct zbud_hdr *)pampd);
atomic_dec(&zcache_curr_eph_pampd_count);
BUG_ON(atomic_read(&zcache_curr_eph_pampd_count) < 0);
if (!is_local_client(pool->client))
dec_and_check(&ramster_foreign_eph_pampd_count);
if (acct)
/* FIXME get these working properly again */
dec_and_check(&zcache_curr_eph_pampd_count);
} else {
zv_free(cli->xvpool, (struct zv_hdr *)pampd);
atomic_dec(&zcache_curr_pers_pampd_count);
BUG_ON(atomic_read(&zcache_curr_pers_pampd_count) < 0);
local_pers:
zv = (struct zv_hdr *)pampd;
if (!is_local_client(pool->client))
dec_and_check(&ramster_foreign_pers_pampd_count);
zv_free(cli->xvpool, zv);
if (acct)
/* FIXME get these working properly again */
dec_and_check(&zcache_curr_pers_pampd_count);
}
}
static void zcache_pampd_free_obj(struct tmem_pool *pool, struct tmem_obj *obj)
static void zcache_pampd_free_obj(struct tmem_pool *pool,
struct tmem_obj *obj)
{
struct flushlist_node *flnode;
BUG_ON(preemptible());
if (obj->extra == NULL)
return;
BUG_ON(!pampd_is_remote(obj->extra));
flnode = ramster_flnode_alloc(pool);
flnode->xh.client_id = pampd_remote_node(obj->extra);
flnode->xh.pool_id = pool->pool_id;
flnode->xh.oid = obj->oid;
flnode->xh.index = FLUSH_ENTIRE_OBJECT;
flnode->rem_op.op = RAMSTER_REMOTIFY_FLUSH_OBJ;
spin_lock(&zcache_rem_op_list_lock);
list_add(&flnode->rem_op.list, &zcache_rem_op_list);
spin_unlock(&zcache_rem_op_list_lock);
}
static void zcache_pampd_new_obj(struct tmem_obj *obj)
void zcache_pampd_new_obj(struct tmem_obj *obj)
{
obj->extra = NULL;
}
static int zcache_pampd_replace_in_obj(void *pampd, struct tmem_obj *obj)
int zcache_pampd_replace_in_obj(void *new_pampd, struct tmem_obj *obj)
{
return -1;
int ret = -1;
if (new_pampd != NULL) {
if (obj->extra == NULL)
obj->extra = new_pampd;
/* enforce that all remote pages in an object reside
* in the same node! */
else if (pampd_remote_node(new_pampd) !=
pampd_remote_node((void *)(obj->extra)))
BUG();
ret = 0;
}
return ret;
}
static bool zcache_pampd_is_remote(void *pampd)
/*
* Called by the message handler after a (still compressed) page has been
* fetched from the remote machine in response to an "is_remote" tmem_get
* or persistent tmem_localify. For a tmem_get, "extra" is the address of
* the page that is to be filled to succesfully resolve the tmem_get; for
* a (persistent) tmem_localify, "extra" is NULL (as the data is placed only
* in the local zcache). "data" points to "size" bytes of (compressed) data
* passed in the message. In the case of a persistent remote get, if
* pre-allocation was successful (see zcache_repatriate_preload), the page
* is placed into both local zcache and at "extra".
*/
int zcache_localify(int pool_id, struct tmem_oid *oidp,
uint32_t index, char *data, size_t size,
void *extra)
{
return 0;
int ret = -ENOENT;
unsigned long flags;
struct tmem_pool *pool;
bool ephemeral, delete = false;
size_t clen = PAGE_SIZE;
void *pampd, *saved_hb;
struct tmem_obj *obj;
pool = zcache_get_pool_by_id(LOCAL_CLIENT, pool_id);
if (unlikely(pool == NULL))
/* pool doesn't exist anymore */
goto out;
ephemeral = is_ephemeral(pool);
local_irq_save(flags); /* FIXME: maybe only disable softirqs? */
pampd = tmem_localify_get_pampd(pool, oidp, index, &obj, &saved_hb);
if (pampd == NULL) {
/* hmmm... must have been a flush while waiting */
#ifdef RAMSTER_TESTING
pr_err("UNTESTED pampd==NULL in zcache_localify\n");
#endif
if (ephemeral)
ramster_remote_eph_pages_unsucc_get++;
else
ramster_remote_pers_pages_unsucc_get++;
obj = NULL;
goto finish;
} else if (unlikely(!pampd_is_remote(pampd))) {
/* hmmm... must have been a dup put while waiting */
#ifdef RAMSTER_TESTING
pr_err("UNTESTED dup while waiting in zcache_localify\n");
#endif
if (ephemeral)
ramster_remote_eph_pages_unsucc_get++;
else
ramster_remote_pers_pages_unsucc_get++;
obj = NULL;
pampd = NULL;
ret = -EEXIST;
goto finish;
} else if (size == 0) {
/* no remote data, delete the local is_remote pampd */
pampd = NULL;
if (ephemeral)
ramster_remote_eph_pages_unsucc_get++;
else
BUG();
delete = true;
goto finish;
}
if (!ephemeral && pampd_is_intransit(pampd)) {
/* localify to zcache */
pampd = pampd_mask_intransit_and_remote(pampd);
zv_copy_to_pampd(pampd, data, size);
} else {
pampd = NULL;
obj = NULL;
}
if (extra != NULL) {
/* decompress direct-to-memory to complete remotify */
ret = lzo1x_decompress_safe((char *)data, size,
(char *)extra, &clen);
BUG_ON(ret != LZO_E_OK);
BUG_ON(clen != PAGE_SIZE);
}
if (ephemeral)
ramster_remote_eph_pages_succ_get++;
else
ramster_remote_pers_pages_succ_get++;
ret = 0;
finish:
tmem_localify_finish(obj, index, pampd, saved_hb, delete);
zcache_put_pool(pool);
local_irq_restore(flags);
out:
return ret;
}
/*
* Called on a remote persistent tmem_get to attempt to preallocate
* local storage for the data contained in the remote persistent page.
* If succesfully preallocated, returns the pampd, marked as remote and
* in_transit. Else returns NULL. Note that the appropriate tmem data
* structure must be locked.
*/
static void *zcache_pampd_repatriate_preload(void *pampd,
struct tmem_pool *pool,
struct tmem_oid *oid,
uint32_t index,
bool *intransit)
{
int clen = pampd_remote_size(pampd);
void *ret_pampd = NULL;
unsigned long flags;
if (!pampd_is_remote(pampd))
BUG();
if (is_ephemeral(pool))
BUG();
if (pampd_is_intransit(pampd)) {
/*
* to avoid multiple allocations (and maybe a memory leak)
* don't preallocate if already in the process of being
* repatriated
*/
*intransit = true;
goto out;
}
*intransit = false;
local_irq_save(flags);
ret_pampd = (void *)zv_alloc(pool, oid, index, clen);
if (ret_pampd != NULL) {
/*
* a pampd is marked intransit if it is remote and space has
* been allocated for it locally (note, only happens for
* persistent pages, in which case the remote copy is freed)
*/
ret_pampd = pampd_mark_intransit(ret_pampd);
dec_and_check(&ramster_remote_pers_pages);
} else
ramster_pers_pages_remote_nomem++;
local_irq_restore(flags);
out:
return ret_pampd;
}
/*
* Called on a remote tmem_get to invoke a message to fetch the page.
* Might sleep so no tmem locks can be held. "extra" is passed
* all the way through the round-trip messaging to zcache_localify.
*/
static int zcache_pampd_repatriate(void *fake_pampd, void *real_pampd,
struct tmem_pool *pool,
struct tmem_oid *oid, uint32_t index,
bool free, void *extra)
{
struct tmem_xhandle xh;
int ret;
if (pampd_is_intransit(real_pampd))
/* have local space pre-reserved, so free remote copy */
free = true;
xh = tmem_xhandle_fill(LOCAL_CLIENT, pool, oid, index);
/* unreliable request/response for now */
ret = ramster_remote_async_get(&xh, free,
pampd_remote_node(fake_pampd),
pampd_remote_size(fake_pampd),
pampd_remote_cksum(fake_pampd),
extra);
#ifdef RAMSTER_TESTING
if (ret != 0 && ret != -ENOENT)
pr_err("TESTING zcache_pampd_repatriate returns, ret=%d\n",
ret);
#endif
return ret;
}
static struct tmem_pamops zcache_pamops = {
.create = zcache_pampd_create,
.get_data = zcache_pampd_get_data,
.get_data_and_free = zcache_pampd_get_data_and_free,
.free = zcache_pampd_free,
.get_data_and_free = zcache_pampd_get_data_and_free,
.free_obj = zcache_pampd_free_obj,
.is_remote = zcache_pampd_is_remote,
.repatriate_preload = zcache_pampd_repatriate_preload,
.repatriate = zcache_pampd_repatriate,
.new_obj = zcache_pampd_new_obj,
.replace_in_obj = zcache_pampd_replace_in_obj,
.is_remote = zcache_pampd_is_remote,
};
/*
......@@ -1327,9 +2229,13 @@ static int zcache_cpu_notifier(struct notifier_block *nb,
per_cpu(zcache_workmem, cpu) =
kzalloc(LZO1X_MEM_COMPRESS,
GFP_KERNEL | __GFP_REPEAT);
per_cpu(zcache_remoteputmem, cpu) =
kzalloc(PAGE_SIZE, GFP_KERNEL | __GFP_REPEAT);
break;
case CPU_DEAD:
case CPU_UP_CANCELED:
kfree(per_cpu(zcache_remoteputmem, cpu));
per_cpu(zcache_remoteputmem, cpu) = NULL;
free_pages((unsigned long)per_cpu(zcache_dstmem, cpu),
LZO_DSTMEM_PAGE_ORDER);
per_cpu(zcache_dstmem, cpu) = NULL;
......@@ -1346,6 +2252,10 @@ static int zcache_cpu_notifier(struct notifier_block *nb,
kmem_cache_free(zcache_obj_cache, kp->obj);
kp->obj = NULL;
}
if (kp->flnode) {
kmem_cache_free(ramster_flnode_cache, kp->flnode);
kp->flnode = NULL;
}
if (kp->page) {
free_page((unsigned long)kp->page);
kp->page = NULL;
......@@ -1402,12 +2312,12 @@ ZCACHE_SYSFS_RO(flush_found);
ZCACHE_SYSFS_RO(flobj_total);
ZCACHE_SYSFS_RO(flobj_found);
ZCACHE_SYSFS_RO(failed_eph_puts);
ZCACHE_SYSFS_RO(nonactive_puts);
ZCACHE_SYSFS_RO(failed_pers_puts);
ZCACHE_SYSFS_RO(zbud_curr_zbytes);
ZCACHE_SYSFS_RO(zbud_cumul_zpages);
ZCACHE_SYSFS_RO(zbud_cumul_zbytes);
ZCACHE_SYSFS_RO(zbud_buddied_count);
ZCACHE_SYSFS_RO(zbpg_unused_list_count);
ZCACHE_SYSFS_RO(evicted_raw_pages);
ZCACHE_SYSFS_RO(evicted_unbuddied_pages);
ZCACHE_SYSFS_RO(evicted_buddied_pages);
......@@ -1416,6 +2326,7 @@ ZCACHE_SYSFS_RO(failed_alloc);
ZCACHE_SYSFS_RO(put_to_flush);
ZCACHE_SYSFS_RO(compress_poor);
ZCACHE_SYSFS_RO(mean_compress_poor);
ZCACHE_SYSFS_RO(policy_percent_exceeded);
ZCACHE_SYSFS_RO_ATOMIC(zbud_curr_raw_pages);
ZCACHE_SYSFS_RO_ATOMIC(zbud_curr_zpages);
ZCACHE_SYSFS_RO_ATOMIC(curr_obj_count);
......@@ -1439,7 +2350,9 @@ static struct attribute *zcache_attrs[] = {
&zcache_flush_found_attr.attr,
&zcache_flobj_found_attr.attr,
&zcache_failed_eph_puts_attr.attr,
&zcache_nonactive_puts_attr.attr,
&zcache_failed_pers_puts_attr.attr,
&zcache_policy_percent_exceeded_attr.attr,
&zcache_compress_poor_attr.attr,
&zcache_mean_compress_poor_attr.attr,
&zcache_zbud_curr_raw_pages_attr.attr,
......@@ -1448,7 +2361,6 @@ static struct attribute *zcache_attrs[] = {
&zcache_zbud_cumul_zpages_attr.attr,
&zcache_zbud_cumul_zbytes_attr.attr,
&zcache_zbud_buddied_count_attr.attr,
&zcache_zbpg_unused_list_count_attr.attr,
&zcache_evicted_raw_pages_attr.attr,
&zcache_evicted_unbuddied_pages_attr.attr,
&zcache_evicted_buddied_pages_attr.attr,
......@@ -1470,6 +2382,202 @@ static struct attribute_group zcache_attr_group = {
.name = "zcache",
};
#define RAMSTER_SYSFS_RO(_name) \
static ssize_t ramster_##_name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%lu\n", ramster_##_name); \
} \
static struct kobj_attribute ramster_##_name##_attr = { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.show = ramster_##_name##_show, \
}
#define RAMSTER_SYSFS_RW(_name) \
static ssize_t ramster_##_name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%lu\n", ramster_##_name); \
} \
static ssize_t ramster_##_name##_store(struct kobject *kobj, \
struct kobj_attribute *attr, const char *buf, size_t count) \
{ \
int err; \
unsigned long enable; \
err = kstrtoul(buf, 10, &enable); \
if (err) \
return -EINVAL; \
ramster_##_name = enable; \
return count; \
} \
static struct kobj_attribute ramster_##_name##_attr = { \
.attr = { .name = __stringify(_name), .mode = 0644 }, \
.show = ramster_##_name##_show, \
.store = ramster_##_name##_store, \
}
#define RAMSTER_SYSFS_RO_ATOMIC(_name) \
static ssize_t ramster_##_name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%d\n", atomic_read(&ramster_##_name)); \
} \
static struct kobj_attribute ramster_##_name##_attr = { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.show = ramster_##_name##_show, \
}
RAMSTER_SYSFS_RO(interface_revision);
RAMSTER_SYSFS_RO_ATOMIC(remote_pers_pages);
RAMSTER_SYSFS_RW(pers_remotify_enable);
RAMSTER_SYSFS_RW(eph_remotify_enable);
RAMSTER_SYSFS_RO(eph_pages_remoted);
RAMSTER_SYSFS_RO(eph_pages_remote_failed);
RAMSTER_SYSFS_RO(pers_pages_remoted);
RAMSTER_SYSFS_RO(pers_pages_remote_failed);
RAMSTER_SYSFS_RO(pers_pages_remote_nomem);
RAMSTER_SYSFS_RO(remote_pages_flushed);
RAMSTER_SYSFS_RO(remote_page_flushes_failed);
RAMSTER_SYSFS_RO(remote_objects_flushed);
RAMSTER_SYSFS_RO(remote_object_flushes_failed);
RAMSTER_SYSFS_RO(remote_eph_pages_succ_get);
RAMSTER_SYSFS_RO(remote_eph_pages_unsucc_get);
RAMSTER_SYSFS_RO(remote_pers_pages_succ_get);
RAMSTER_SYSFS_RO(remote_pers_pages_unsucc_get);
RAMSTER_SYSFS_RO_ATOMIC(foreign_eph_pampd_count);
RAMSTER_SYSFS_RO(foreign_eph_pampd_count_max);
RAMSTER_SYSFS_RO_ATOMIC(foreign_pers_pampd_count);
RAMSTER_SYSFS_RO(foreign_pers_pampd_count_max);
RAMSTER_SYSFS_RO_ATOMIC(curr_flnode_count);
RAMSTER_SYSFS_RO(curr_flnode_count_max);
#define MANUAL_NODES 8
static bool ramster_nodes_manual_up[MANUAL_NODES];
static ssize_t ramster_manual_node_up_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
int i;
char *p = buf;
for (i = 0; i < MANUAL_NODES; i++)
if (ramster_nodes_manual_up[i])
p += sprintf(p, "%d ", i);
p += sprintf(p, "\n");
return p - buf;
}
static ssize_t ramster_manual_node_up_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
int err;
unsigned long node_num;
err = kstrtoul(buf, 10, &node_num);
if (err) {
pr_err("ramster: bad strtoul?\n");
return -EINVAL;
}
if (node_num >= MANUAL_NODES) {
pr_err("ramster: bad node_num=%lu?\n", node_num);
return -EINVAL;
}
if (ramster_nodes_manual_up[node_num]) {
pr_err("ramster: node %d already up, ignoring\n",
(int)node_num);
} else {
ramster_nodes_manual_up[node_num] = true;
r2net_hb_node_up_manual((int)node_num);
}
return count;
}
static struct kobj_attribute ramster_manual_node_up_attr = {
.attr = { .name = "manual_node_up", .mode = 0644 },
.show = ramster_manual_node_up_show,
.store = ramster_manual_node_up_store,
};
static ssize_t ramster_remote_target_nodenum_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
if (ramster_remote_target_nodenum == -1UL)
return sprintf(buf, "unset\n");
else
return sprintf(buf, "%d\n", ramster_remote_target_nodenum);
}
static ssize_t ramster_remote_target_nodenum_store(struct kobject *kobj,
struct kobj_attribute *attr, const char *buf, size_t count)
{
int err;
unsigned long node_num;
err = kstrtoul(buf, 10, &node_num);
if (err) {
pr_err("ramster: bad strtoul?\n");
return -EINVAL;
} else if (node_num == -1UL) {
pr_err("ramster: disabling all remotification, "
"data may still reside on remote nodes however\n");
return -EINVAL;
} else if (node_num >= MANUAL_NODES) {
pr_err("ramster: bad node_num=%lu?\n", node_num);
return -EINVAL;
} else if (!ramster_nodes_manual_up[node_num]) {
pr_err("ramster: node %d not up, ignoring setting "
"of remotification target\n", (int)node_num);
} else if (r2net_remote_target_node_set((int)node_num) >= 0) {
pr_info("ramster: node %d set as remotification target\n",
(int)node_num);
ramster_remote_target_nodenum = (int)node_num;
} else {
pr_err("ramster: bad num to node node_num=%d?\n",
(int)node_num);
return -EINVAL;
}
return count;
}
static struct kobj_attribute ramster_remote_target_nodenum_attr = {
.attr = { .name = "remote_target_nodenum", .mode = 0644 },
.show = ramster_remote_target_nodenum_show,
.store = ramster_remote_target_nodenum_store,
};
static struct attribute *ramster_attrs[] = {
&ramster_interface_revision_attr.attr,
&ramster_pers_remotify_enable_attr.attr,
&ramster_eph_remotify_enable_attr.attr,
&ramster_remote_pers_pages_attr.attr,
&ramster_eph_pages_remoted_attr.attr,
&ramster_eph_pages_remote_failed_attr.attr,
&ramster_pers_pages_remoted_attr.attr,
&ramster_pers_pages_remote_failed_attr.attr,
&ramster_pers_pages_remote_nomem_attr.attr,
&ramster_remote_pages_flushed_attr.attr,
&ramster_remote_page_flushes_failed_attr.attr,
&ramster_remote_objects_flushed_attr.attr,
&ramster_remote_object_flushes_failed_attr.attr,
&ramster_remote_eph_pages_succ_get_attr.attr,
&ramster_remote_eph_pages_unsucc_get_attr.attr,
&ramster_remote_pers_pages_succ_get_attr.attr,
&ramster_remote_pers_pages_unsucc_get_attr.attr,
&ramster_foreign_eph_pampd_count_attr.attr,
&ramster_foreign_eph_pampd_count_max_attr.attr,
&ramster_foreign_pers_pampd_count_attr.attr,
&ramster_foreign_pers_pampd_count_max_attr.attr,
&ramster_curr_flnode_count_attr.attr,
&ramster_curr_flnode_count_max_attr.attr,
&ramster_manual_node_up_attr.attr,
&ramster_remote_target_nodenum_attr.attr,
NULL,
};
static struct attribute_group ramster_attr_group = {
.attrs = ramster_attrs,
.name = "ramster",
};
#endif /* CONFIG_SYSFS */
/*
* When zcache is disabled ("frozen"), pools can be created and destroyed,
......@@ -1510,8 +2618,9 @@ static struct shrinker zcache_shrinker = {
* zcache shims between cleancache/frontswap ops and tmem
*/
static int zcache_put_page(int cli_id, int pool_id, struct tmem_oid *oidp,
uint32_t index, struct page *page)
int zcache_put(int cli_id, int pool_id, struct tmem_oid *oidp,
uint32_t index, char *data, size_t size,
bool raw, int ephemeral)
{
struct tmem_pool *pool;
int ret = -1;
......@@ -1522,8 +2631,7 @@ static int zcache_put_page(int cli_id, int pool_id, struct tmem_oid *oidp,
goto out;
if (!zcache_freeze && zcache_do_preload(pool) == 0) {
/* preload does preempt_disable on success */
ret = tmem_put(pool, oidp, index, (char *)(page),
PAGE_SIZE, 0, is_ephemeral(pool));
ret = tmem_put(pool, oidp, index, data, size, raw, ephemeral);
if (ret < 0) {
if (is_ephemeral(pool))
zcache_failed_eph_puts++;
......@@ -1543,27 +2651,38 @@ static int zcache_put_page(int cli_id, int pool_id, struct tmem_oid *oidp,
return ret;
}
static int zcache_get_page(int cli_id, int pool_id, struct tmem_oid *oidp,
uint32_t index, struct page *page)
int zcache_get(int cli_id, int pool_id, struct tmem_oid *oidp,
uint32_t index, char *data, size_t *sizep,
bool raw, int get_and_free)
{
struct tmem_pool *pool;
int ret = -1;
unsigned long flags;
size_t size = PAGE_SIZE;
bool eph;
local_irq_save(flags);
if (!raw) {
BUG_ON(irqs_disabled());
BUG_ON(in_softirq());
}
pool = zcache_get_pool_by_id(cli_id, pool_id);
eph = is_ephemeral(pool);
if (likely(pool != NULL)) {
if (atomic_read(&pool->obj_count) > 0)
ret = tmem_get(pool, oidp, index, (char *)(page),
&size, 0, is_ephemeral(pool));
ret = tmem_get(pool, oidp, index, data, sizep,
raw, get_and_free);
zcache_put_pool(pool);
}
local_irq_restore(flags);
WARN_ONCE((!eph && (ret != 0)), "zcache_get fails on persistent pool, "
"bad things are very likely to happen soon\n");
#ifdef RAMSTER_TESTING
if (ret != 0 && ret != -1 && !(ret == -EINVAL && is_ephemeral(pool)))
pr_err("TESTING zcache_get tmem_get returns ret=%d\n", ret);
#endif
if (ret == -EAGAIN)
BUG(); /* FIXME... don't need this anymore??? let's ensure */
return ret;
}
static int zcache_flush_page(int cli_id, int pool_id,
int zcache_flush(int cli_id, int pool_id,
struct tmem_oid *oidp, uint32_t index)
{
struct tmem_pool *pool;
......@@ -1573,6 +2692,7 @@ static int zcache_flush_page(int cli_id, int pool_id,
local_irq_save(flags);
zcache_flush_total++;
pool = zcache_get_pool_by_id(cli_id, pool_id);
ramster_do_preload_flnode_only(pool);
if (likely(pool != NULL)) {
if (atomic_read(&pool->obj_count) > 0)
ret = tmem_flush_page(pool, oidp, index);
......@@ -1584,8 +2704,7 @@ static int zcache_flush_page(int cli_id, int pool_id,
return ret;
}
static int zcache_flush_object(int cli_id, int pool_id,
struct tmem_oid *oidp)
int zcache_flush_object(int cli_id, int pool_id, struct tmem_oid *oidp)
{
struct tmem_pool *pool;
int ret = -1;
......@@ -1594,6 +2713,7 @@ static int zcache_flush_object(int cli_id, int pool_id,
local_irq_save(flags);
zcache_flobj_total++;
pool = zcache_get_pool_by_id(cli_id, pool_id);
ramster_do_preload_flnode_only(pool);
if (likely(pool != NULL)) {
if (atomic_read(&pool->obj_count) > 0)
ret = tmem_flush_object(pool, oidp);
......@@ -1605,7 +2725,7 @@ static int zcache_flush_object(int cli_id, int pool_id,
return ret;
}
static int zcache_destroy_pool(int cli_id, int pool_id)
int zcache_client_destroy_pool(int cli_id, int pool_id)
{
struct tmem_pool *pool = NULL;
struct zcache_client *cli = NULL;
......@@ -1632,13 +2752,17 @@ static int zcache_destroy_pool(int cli_id, int pool_id)
ret = tmem_destroy_pool(pool);
local_bh_enable();
kfree(pool);
pr_info("zcache: destroyed pool id=%d, cli_id=%d\n",
pool_id, cli_id);
pr_info("ramster: destroyed pool id=%d cli_id=%d\n", pool_id, cli_id);
out:
return ret;
}
static int zcache_new_pool(uint16_t cli_id, uint32_t flags)
static int zcache_destroy_pool(int pool_id)
{
return zcache_client_destroy_pool(LOCAL_CLIENT, pool_id);
}
int zcache_new_pool(uint16_t cli_id, uint32_t flags)
{
int poolid = -1;
struct tmem_pool *pool;
......@@ -1653,7 +2777,7 @@ static int zcache_new_pool(uint16_t cli_id, uint32_t flags)
atomic_inc(&cli->refcount);
pool = kmalloc(sizeof(struct tmem_pool), GFP_ATOMIC);
if (pool == NULL) {
pr_info("zcache: pool creation failed: out of memory\n");
pr_info("ramster: pool creation failed: out of memory\n");
goto out;
}
......@@ -1661,7 +2785,7 @@ static int zcache_new_pool(uint16_t cli_id, uint32_t flags)
if (cli->tmem_pools[poolid] == NULL)
break;
if (poolid >= MAX_POOLS_PER_CLIENT) {
pr_info("zcache: pool creation failed: max exceeded\n");
pr_info("ramster: pool creation failed: max exceeded\n");
kfree(pool);
poolid = -1;
goto out;
......@@ -1671,15 +2795,78 @@ static int zcache_new_pool(uint16_t cli_id, uint32_t flags)
pool->pool_id = poolid;
tmem_new_pool(pool, flags);
cli->tmem_pools[poolid] = pool;
pr_info("zcache: created %s tmem pool, id=%d, client=%d\n",
flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
poolid, cli_id);
if (cli_id == LOCAL_CLIENT)
pr_info("ramster: created %s tmem pool, id=%d, local client\n",
flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
poolid);
else
pr_info("ramster: created %s tmem pool, id=%d, client=%d\n",
flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
poolid, cli_id);
out:
if (cli != NULL)
atomic_dec(&cli->refcount);
return poolid;
}
static int zcache_local_new_pool(uint32_t flags)
{
return zcache_new_pool(LOCAL_CLIENT, flags);
}
int zcache_autocreate_pool(int cli_id, int pool_id, bool ephemeral)
{
struct tmem_pool *pool;
struct zcache_client *cli = NULL;
uint32_t flags = ephemeral ? 0 : TMEM_POOL_PERSIST;
int ret = -1;
if (cli_id == LOCAL_CLIENT)
goto out;
if (pool_id >= MAX_POOLS_PER_CLIENT)
goto out;
else if ((unsigned int)cli_id < MAX_CLIENTS)
cli = &zcache_clients[cli_id];
if ((ephemeral && !use_cleancache) || (!ephemeral && !use_frontswap))
BUG(); /* FIXME, handle more gracefully later */
if (!cli->allocated) {
if (zcache_new_client(cli_id))
BUG(); /* FIXME, handle more gracefully later */
cli = &zcache_clients[cli_id];
}
atomic_inc(&cli->refcount);
pool = cli->tmem_pools[pool_id];
if (pool != NULL) {
if (pool->persistent && ephemeral) {
pr_err("zcache_autocreate_pool: type mismatch\n");
goto out;
}
ret = 0;
goto out;
}
pool = kmalloc(sizeof(struct tmem_pool), GFP_KERNEL);
if (pool == NULL) {
pr_info("ramster: pool creation failed: out of memory\n");
goto out;
}
atomic_set(&pool->refcount, 0);
pool->client = cli;
pool->pool_id = pool_id;
tmem_new_pool(pool, flags);
cli->tmem_pools[pool_id] = pool;
pr_info("ramster: AUTOcreated %s tmem poolid=%d, for remote client=%d\n",
flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
pool_id, cli_id);
ret = 0;
out:
if (cli == NULL)
BUG(); /* FIXME, handle more gracefully later */
/* pr_err("zcache_autocreate_pool: failed\n"); */
if (cli != NULL)
atomic_dec(&cli->refcount);
return ret;
}
/**********
* Two kernel functionalities currently can be layered on top of tmem.
* These are "cleancache" which is used as a second-chance cache for clean
......@@ -1696,8 +2883,18 @@ static void zcache_cleancache_put_page(int pool_id,
u32 ind = (u32) index;
struct tmem_oid oid = *(struct tmem_oid *)&key;
if (likely(ind == index))
(void)zcache_put_page(LOCAL_CLIENT, pool_id, &oid, index, page);
#ifdef __PG_WAS_ACTIVE
if (!PageWasActive(page)) {
zcache_nonactive_puts++;
return;
}
#endif
if (likely(ind == index)) {
char *kva = page_address(page);
(void)zcache_put(LOCAL_CLIENT, pool_id, &oid, index,
kva, PAGE_SIZE, 0, 1);
}
}
static int zcache_cleancache_get_page(int pool_id,
......@@ -1708,8 +2905,19 @@ static int zcache_cleancache_get_page(int pool_id,
struct tmem_oid oid = *(struct tmem_oid *)&key;
int ret = -1;
if (likely(ind == index))
ret = zcache_get_page(LOCAL_CLIENT, pool_id, &oid, index, page);
preempt_disable();
if (likely(ind == index)) {
char *kva = page_address(page);
size_t size = PAGE_SIZE;
ret = zcache_get(LOCAL_CLIENT, pool_id, &oid, index,
kva, &size, 0, 0);
#ifdef __PG_WAS_ACTIVE
if (ret == 0)
SetPageWasActive(page);
#endif
}
preempt_enable();
return ret;
}
......@@ -1721,7 +2929,7 @@ static void zcache_cleancache_flush_page(int pool_id,
struct tmem_oid oid = *(struct tmem_oid *)&key;
if (likely(ind == index))
(void)zcache_flush_page(LOCAL_CLIENT, pool_id, &oid, ind);
(void)zcache_flush(LOCAL_CLIENT, pool_id, &oid, ind);
}
static void zcache_cleancache_flush_inode(int pool_id,
......@@ -1735,7 +2943,7 @@ static void zcache_cleancache_flush_inode(int pool_id,
static void zcache_cleancache_flush_fs(int pool_id)
{
if (pool_id >= 0)
(void)zcache_destroy_pool(LOCAL_CLIENT, pool_id);
(void)zcache_destroy_pool(pool_id);
}
static int zcache_cleancache_init_fs(size_t pagesize)
......@@ -1743,7 +2951,7 @@ static int zcache_cleancache_init_fs(size_t pagesize)
BUG_ON(sizeof(struct cleancache_filekey) !=
sizeof(struct tmem_oid));
BUG_ON(pagesize != PAGE_SIZE);
return zcache_new_pool(LOCAL_CLIENT, 0);
return zcache_local_new_pool(0);
}
static int zcache_cleancache_init_shared_fs(char *uuid, size_t pagesize)
......@@ -1752,7 +2960,7 @@ static int zcache_cleancache_init_shared_fs(char *uuid, size_t pagesize)
BUG_ON(sizeof(struct cleancache_filekey) !=
sizeof(struct tmem_oid));
BUG_ON(pagesize != PAGE_SIZE);
return zcache_new_pool(LOCAL_CLIENT, 0);
return zcache_local_new_pool(0);
}
static struct cleancache_ops zcache_cleancache_ops = {
......@@ -1781,10 +2989,8 @@ static int zcache_frontswap_poolid = -1;
/*
* Swizzling increases objects per swaptype, increasing tmem concurrency
* for heavy swaploads. Later, larger nr_cpus -> larger SWIZ_BITS
* Setting SWIZ_BITS to 27 basically reconstructs the swap entry from
* frontswap_get_page()
*/
#define SWIZ_BITS 27
#define SWIZ_BITS 8
#define SWIZ_MASK ((1 << SWIZ_BITS) - 1)
#define _oswiz(_type, _ind) ((_type << SWIZ_BITS) | (_ind & SWIZ_MASK))
#define iswiz(_ind) (_ind >> SWIZ_BITS)
......@@ -1804,12 +3010,14 @@ static int zcache_frontswap_put_page(unsigned type, pgoff_t offset,
struct tmem_oid oid = oswiz(type, ind);
int ret = -1;
unsigned long flags;
char *kva;
BUG_ON(!PageLocked(page));
if (likely(ind64 == ind)) {
local_irq_save(flags);
ret = zcache_put_page(LOCAL_CLIENT, zcache_frontswap_poolid,
&oid, iswiz(ind), page);
kva = page_address(page);
ret = zcache_put(LOCAL_CLIENT, zcache_frontswap_poolid,
&oid, iswiz(ind), kva, PAGE_SIZE, 0, 0);
local_irq_restore(flags);
}
return ret;
......@@ -1825,10 +3033,16 @@ static int zcache_frontswap_get_page(unsigned type, pgoff_t offset,
struct tmem_oid oid = oswiz(type, ind);
int ret = -1;
preempt_disable(); /* FIXME, remove this? */
BUG_ON(!PageLocked(page));
if (likely(ind64 == ind))
ret = zcache_get_page(LOCAL_CLIENT, zcache_frontswap_poolid,
&oid, iswiz(ind), page);
if (likely(ind64 == ind)) {
char *kva = page_address(page);
size_t size = PAGE_SIZE;
ret = zcache_get(LOCAL_CLIENT, zcache_frontswap_poolid,
&oid, iswiz(ind), kva, &size, 0, -1);
}
preempt_enable(); /* FIXME, remove this? */
return ret;
}
......@@ -1840,7 +3054,7 @@ static void zcache_frontswap_flush_page(unsigned type, pgoff_t offset)
struct tmem_oid oid = oswiz(type, ind);
if (likely(ind64 == ind))
(void)zcache_flush_page(LOCAL_CLIENT, zcache_frontswap_poolid,
(void)zcache_flush(LOCAL_CLIENT, zcache_frontswap_poolid,
&oid, iswiz(ind));
}
......@@ -1862,7 +3076,7 @@ static void zcache_frontswap_init(unsigned ignored)
/* a single tmem poolid is used for all frontswap "types" (swapfiles) */
if (zcache_frontswap_poolid < 0)
zcache_frontswap_poolid =
zcache_new_pool(LOCAL_CLIENT, TMEM_POOL_PERSIST);
zcache_local_new_pool(TMEM_POOL_PERSIST);
}
static struct frontswap_ops zcache_frontswap_ops = {
......@@ -1882,20 +3096,126 @@ struct frontswap_ops zcache_frontswap_register_ops(void)
}
#endif
/*
* frontswap selfshrinking
*/
#ifdef CONFIG_FRONTSWAP
/* In HZ, controls frequency of worker invocation. */
static unsigned int selfshrink_interval __read_mostly = 5;
static void selfshrink_process(struct work_struct *work);
static DECLARE_DELAYED_WORK(selfshrink_worker, selfshrink_process);
/* Enable/disable with sysfs. */
static bool frontswap_selfshrinking __read_mostly;
/* Enable/disable with kernel boot option. */
static bool use_frontswap_selfshrink __initdata = true;
/*
* The default values for the following parameters were deemed reasonable
* by experimentation, may be workload-dependent, and can all be
* adjusted via sysfs.
*/
/* Control rate for frontswap shrinking. Higher hysteresis is slower. */
static unsigned int frontswap_hysteresis __read_mostly = 20;
/*
* Number of selfshrink worker invocations to wait before observing that
* frontswap selfshrinking should commence. Note that selfshrinking does
* not use a separate worker thread.
*/
static unsigned int frontswap_inertia __read_mostly = 3;
/* Countdown to next invocation of frontswap_shrink() */
static unsigned long frontswap_inertia_counter;
/*
* Invoked by the selfshrink worker thread, uses current number of pages
* in frontswap (frontswap_curr_pages()), previous status, and control
* values (hysteresis and inertia) to determine if frontswap should be
* shrunk and what the new frontswap size should be. Note that
* frontswap_shrink is essentially a partial swapoff that immediately
* transfers pages from the "swap device" (frontswap) back into kernel
* RAM; despite the name, frontswap "shrinking" is very different from
* the "shrinker" interface used by the kernel MM subsystem to reclaim
* memory.
*/
static void frontswap_selfshrink(void)
{
static unsigned long cur_frontswap_pages;
static unsigned long last_frontswap_pages;
static unsigned long tgt_frontswap_pages;
last_frontswap_pages = cur_frontswap_pages;
cur_frontswap_pages = frontswap_curr_pages();
if (!cur_frontswap_pages ||
(cur_frontswap_pages > last_frontswap_pages)) {
frontswap_inertia_counter = frontswap_inertia;
return;
}
if (frontswap_inertia_counter && --frontswap_inertia_counter)
return;
if (cur_frontswap_pages <= frontswap_hysteresis)
tgt_frontswap_pages = 0;
else
tgt_frontswap_pages = cur_frontswap_pages -
(cur_frontswap_pages / frontswap_hysteresis);
frontswap_shrink(tgt_frontswap_pages);
}
static int __init ramster_nofrontswap_selfshrink_setup(char *s)
{
use_frontswap_selfshrink = false;
return 1;
}
__setup("noselfshrink", ramster_nofrontswap_selfshrink_setup);
static void selfshrink_process(struct work_struct *work)
{
if (frontswap_selfshrinking && frontswap_enabled) {
frontswap_selfshrink();
schedule_delayed_work(&selfshrink_worker,
selfshrink_interval * HZ);
}
}
static int ramster_enabled;
static int __init ramster_selfshrink_init(void)
{
frontswap_selfshrinking = ramster_enabled && use_frontswap_selfshrink;
if (frontswap_selfshrinking)
pr_info("ramster: Initializing frontswap "
"selfshrinking driver.\n");
else
return -ENODEV;
schedule_delayed_work(&selfshrink_worker, selfshrink_interval * HZ);
return 0;
}
subsys_initcall(ramster_selfshrink_init);
#endif
/*
* zcache initialization
* NOTE FOR NOW zcache MUST BE PROVIDED AS A KERNEL BOOT PARAMETER OR
* NOTE FOR NOW ramster MUST BE PROVIDED AS A KERNEL BOOT PARAMETER OR
* NOTHING HAPPENS!
*/
static int zcache_enabled;
static int ramster_enabled;
static int __init enable_zcache(char *s)
static int __init enable_ramster(char *s)
{
zcache_enabled = 1;
ramster_enabled = 1;
return 1;
}
__setup("zcache", enable_zcache);
__setup("ramster", enable_ramster);
/* allow independent dynamic disabling of cleancache and frontswap */
......@@ -1903,16 +3223,22 @@ static int use_cleancache = 1;
static int __init no_cleancache(char *s)
{
pr_info("INIT no_cleancache called\n");
use_cleancache = 0;
return 1;
}
__setup("nocleancache", no_cleancache);
/*
* FIXME: need to guarantee this gets checked before zcache_init is called
* What is the correct way to achieve this?
*/
early_param("nocleancache", no_cleancache);
static int use_frontswap = 1;
static int __init no_frontswap(char *s)
{
pr_info("INIT no_frontswap called\n");
use_frontswap = 0;
return 1;
}
......@@ -1925,20 +3251,22 @@ static int __init zcache_init(void)
#ifdef CONFIG_SYSFS
ret = sysfs_create_group(mm_kobj, &zcache_attr_group);
ret = sysfs_create_group(mm_kobj, &ramster_attr_group);
if (ret) {
pr_err("zcache: can't create sysfs\n");
pr_err("ramster: can't create sysfs\n");
goto out;
}
#endif /* CONFIG_SYSFS */
#if defined(CONFIG_CLEANCACHE) || defined(CONFIG_FRONTSWAP)
if (zcache_enabled) {
if (ramster_enabled) {
unsigned int cpu;
(void)r2net_register_handlers();
tmem_register_hostops(&zcache_hostops);
tmem_register_pamops(&zcache_pamops);
ret = register_cpu_notifier(&zcache_cpu_notifier_block);
if (ret) {
pr_err("zcache: can't register cpu notifier\n");
pr_err("ramster: can't register cpu notifier\n");
goto out;
}
for_each_online_cpu(cpu) {
......@@ -1951,35 +3279,39 @@ static int __init zcache_init(void)
sizeof(struct tmem_objnode), 0, 0, NULL);
zcache_obj_cache = kmem_cache_create("zcache_obj",
sizeof(struct tmem_obj), 0, 0, NULL);
ret = zcache_new_client(LOCAL_CLIENT);
if (ret) {
pr_err("zcache: can't create client\n");
goto out;
}
ramster_flnode_cache = kmem_cache_create("ramster_flnode",
sizeof(struct flushlist_node), 0, 0, NULL);
#endif
#ifdef CONFIG_CLEANCACHE
if (zcache_enabled && use_cleancache) {
pr_info("INIT ramster_enabled=%d use_cleancache=%d\n",
ramster_enabled, use_cleancache);
if (ramster_enabled && use_cleancache) {
struct cleancache_ops old_ops;
zbud_init();
register_shrinker(&zcache_shrinker);
old_ops = zcache_cleancache_register_ops();
pr_info("zcache: cleancache enabled using kernel "
pr_info("ramster: cleancache enabled using kernel "
"transcendent memory and compression buddies\n");
if (old_ops.init_fs != NULL)
pr_warning("zcache: cleancache_ops overridden");
pr_warning("ramster: cleancache_ops overridden");
}
#endif
#ifdef CONFIG_FRONTSWAP
if (zcache_enabled && use_frontswap) {
pr_info("INIT ramster_enabled=%d use_frontswap=%d\n",
ramster_enabled, use_frontswap);
if (ramster_enabled && use_frontswap) {
struct frontswap_ops old_ops;
zcache_new_client(LOCAL_CLIENT);
old_ops = zcache_frontswap_register_ops();
pr_info("zcache: frontswap enabled using kernel "
pr_info("ramster: frontswap enabled using kernel "
"transcendent memory and xvmalloc\n");
if (old_ops.init != NULL)
pr_warning("zcache: frontswap_ops overridden");
pr_warning("ramster: frontswap_ops overridden");
}
if (ramster_enabled && (use_frontswap || use_cleancache))
ramster_remotify_init();
#endif
out:
return ret;
......
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