mirror_zfs/include/sys/kmem_cache.h
Brian Behlendorf 9b13f65d28 Fix CPU hotplug
Allocate a kmem cache magazine for every possible CPU which might
be added to the system.  This ensures that when one of these CPUs
is enabled it can be safely used immediately.

For many systems the number of online CPUs is identical to the
number of present CPUs so this does imply an increased memory
footprint.  In fact, dynamically allocating the array of magazine
pointers instead of using the worst case NR_CPUS can end up
decreasing our memory footprint.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #482
2015-10-13 09:50:40 -07:00

241 lines
9.6 KiB
C

/*
* Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
* Copyright (C) 2007 The Regents of the University of California.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* UCRL-CODE-235197
*
* This file is part of the SPL, Solaris Porting Layer.
* For details, see <http://zfsonlinux.org/>.
*
* The SPL is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* The SPL is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with the SPL. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _SPL_KMEM_CACHE_H
#define _SPL_KMEM_CACHE_H
#include <sys/taskq.h>
/*
* Slab allocation interfaces. The SPL slab differs from the standard
* Linux SLAB or SLUB primarily in that each cache may be backed by slabs
* allocated from the physical or virtal memory address space. The virtual
* slabs allow for good behavior when allocation large objects of identical
* size. This slab implementation also supports both constructors and
* destructors which the Linux slab does not.
*/
enum {
KMC_BIT_NOTOUCH = 0, /* Don't update ages */
KMC_BIT_NODEBUG = 1, /* Default behavior */
KMC_BIT_NOMAGAZINE = 2, /* XXX: Unsupported */
KMC_BIT_NOHASH = 3, /* XXX: Unsupported */
KMC_BIT_QCACHE = 4, /* XXX: Unsupported */
KMC_BIT_KMEM = 5, /* Use kmem cache */
KMC_BIT_VMEM = 6, /* Use vmem cache */
KMC_BIT_SLAB = 7, /* Use Linux slab cache */
KMC_BIT_OFFSLAB = 8, /* Objects not on slab */
KMC_BIT_NOEMERGENCY = 9, /* Disable emergency objects */
KMC_BIT_DEADLOCKED = 14, /* Deadlock detected */
KMC_BIT_GROWING = 15, /* Growing in progress */
KMC_BIT_REAPING = 16, /* Reaping in progress */
KMC_BIT_DESTROY = 17, /* Destroy in progress */
KMC_BIT_TOTAL = 18, /* Proc handler helper bit */
KMC_BIT_ALLOC = 19, /* Proc handler helper bit */
KMC_BIT_MAX = 20, /* Proc handler helper bit */
};
/* kmem move callback return values */
typedef enum kmem_cbrc {
KMEM_CBRC_YES = 0, /* Object moved */
KMEM_CBRC_NO = 1, /* Object not moved */
KMEM_CBRC_LATER = 2, /* Object not moved, try again later */
KMEM_CBRC_DONT_NEED = 3, /* Neither object is needed */
KMEM_CBRC_DONT_KNOW = 4, /* Object unknown */
} kmem_cbrc_t;
#define KMC_NOTOUCH (1 << KMC_BIT_NOTOUCH)
#define KMC_NODEBUG (1 << KMC_BIT_NODEBUG)
#define KMC_NOMAGAZINE (1 << KMC_BIT_NOMAGAZINE)
#define KMC_NOHASH (1 << KMC_BIT_NOHASH)
#define KMC_QCACHE (1 << KMC_BIT_QCACHE)
#define KMC_KMEM (1 << KMC_BIT_KMEM)
#define KMC_VMEM (1 << KMC_BIT_VMEM)
#define KMC_SLAB (1 << KMC_BIT_SLAB)
#define KMC_OFFSLAB (1 << KMC_BIT_OFFSLAB)
#define KMC_NOEMERGENCY (1 << KMC_BIT_NOEMERGENCY)
#define KMC_DEADLOCKED (1 << KMC_BIT_DEADLOCKED)
#define KMC_GROWING (1 << KMC_BIT_GROWING)
#define KMC_REAPING (1 << KMC_BIT_REAPING)
#define KMC_DESTROY (1 << KMC_BIT_DESTROY)
#define KMC_TOTAL (1 << KMC_BIT_TOTAL)
#define KMC_ALLOC (1 << KMC_BIT_ALLOC)
#define KMC_MAX (1 << KMC_BIT_MAX)
#define KMC_REAP_CHUNK INT_MAX
#define KMC_DEFAULT_SEEKS 1
#define KMC_EXPIRE_AGE 0x1 /* Due to age */
#define KMC_EXPIRE_MEM 0x2 /* Due to low memory */
#define KMC_RECLAIM_ONCE 0x1 /* Force a single shrinker pass */
extern unsigned int spl_kmem_cache_expire;
extern struct list_head spl_kmem_cache_list;
extern struct rw_semaphore spl_kmem_cache_sem;
#define SKM_MAGIC 0x2e2e2e2e
#define SKO_MAGIC 0x20202020
#define SKS_MAGIC 0x22222222
#define SKC_MAGIC 0x2c2c2c2c
#define SPL_KMEM_CACHE_DELAY 15 /* Minimum slab release age */
#define SPL_KMEM_CACHE_REAP 0 /* Default reap everything */
#define SPL_KMEM_CACHE_OBJ_PER_SLAB 8 /* Target objects per slab */
#define SPL_KMEM_CACHE_OBJ_PER_SLAB_MIN 1 /* Minimum objects per slab */
#define SPL_KMEM_CACHE_ALIGN 8 /* Default object alignment */
#ifdef _LP64
#define SPL_KMEM_CACHE_MAX_SIZE 32 /* Max slab size in MB */
#else
#define SPL_KMEM_CACHE_MAX_SIZE 4 /* Max slab size in MB */
#endif
#define SPL_MAX_ORDER (MAX_ORDER - 3)
#define SPL_MAX_ORDER_NR_PAGES (1 << (SPL_MAX_ORDER - 1))
#ifdef CONFIG_SLUB
#define SPL_MAX_KMEM_CACHE_ORDER PAGE_ALLOC_COSTLY_ORDER
#define SPL_MAX_KMEM_ORDER_NR_PAGES (1 << (SPL_MAX_KMEM_CACHE_ORDER - 1))
#else
#define SPL_MAX_KMEM_ORDER_NR_PAGES (KMALLOC_MAX_SIZE >> PAGE_SHIFT)
#endif
#define POINTER_IS_VALID(p) 0 /* Unimplemented */
#define POINTER_INVALIDATE(pp) /* Unimplemented */
typedef int (*spl_kmem_ctor_t)(void *, void *, int);
typedef void (*spl_kmem_dtor_t)(void *, void *);
typedef void (*spl_kmem_reclaim_t)(void *);
typedef struct spl_kmem_magazine {
uint32_t skm_magic; /* Sanity magic */
uint32_t skm_avail; /* Available objects */
uint32_t skm_size; /* Magazine size */
uint32_t skm_refill; /* Batch refill size */
struct spl_kmem_cache *skm_cache; /* Owned by cache */
unsigned long skm_age; /* Last cache access */
unsigned int skm_cpu; /* Owned by cpu */
void *skm_objs[0]; /* Object pointers */
} spl_kmem_magazine_t;
typedef struct spl_kmem_obj {
uint32_t sko_magic; /* Sanity magic */
void *sko_addr; /* Buffer address */
struct spl_kmem_slab *sko_slab; /* Owned by slab */
struct list_head sko_list; /* Free object list linkage */
} spl_kmem_obj_t;
typedef struct spl_kmem_slab {
uint32_t sks_magic; /* Sanity magic */
uint32_t sks_objs; /* Objects per slab */
struct spl_kmem_cache *sks_cache; /* Owned by cache */
struct list_head sks_list; /* Slab list linkage */
struct list_head sks_free_list; /* Free object list */
unsigned long sks_age; /* Last modify jiffie */
uint32_t sks_ref; /* Ref count used objects */
} spl_kmem_slab_t;
typedef struct spl_kmem_alloc {
struct spl_kmem_cache *ska_cache; /* Owned by cache */
int ska_flags; /* Allocation flags */
taskq_ent_t ska_tqe; /* Task queue entry */
} spl_kmem_alloc_t;
typedef struct spl_kmem_emergency {
struct rb_node ske_node; /* Emergency tree linkage */
unsigned long ske_obj; /* Buffer address */
} spl_kmem_emergency_t;
typedef struct spl_kmem_cache {
uint32_t skc_magic; /* Sanity magic */
uint32_t skc_name_size; /* Name length */
char *skc_name; /* Name string */
spl_kmem_magazine_t **skc_mag; /* Per-CPU warm cache */
uint32_t skc_mag_size; /* Magazine size */
uint32_t skc_mag_refill; /* Magazine refill count */
spl_kmem_ctor_t skc_ctor; /* Constructor */
spl_kmem_dtor_t skc_dtor; /* Destructor */
spl_kmem_reclaim_t skc_reclaim; /* Reclaimator */
void *skc_private; /* Private data */
void *skc_vmp; /* Unused */
struct kmem_cache *skc_linux_cache; /* Linux slab cache if used */
unsigned long skc_flags; /* Flags */
uint32_t skc_obj_size; /* Object size */
uint32_t skc_obj_align; /* Object alignment */
uint32_t skc_slab_objs; /* Objects per slab */
uint32_t skc_slab_size; /* Slab size */
uint32_t skc_delay; /* Slab reclaim interval */
uint32_t skc_reap; /* Slab reclaim count */
atomic_t skc_ref; /* Ref count callers */
taskqid_t skc_taskqid; /* Slab reclaim task */
struct list_head skc_list; /* List of caches linkage */
struct list_head skc_complete_list; /* Completely alloc'ed */
struct list_head skc_partial_list; /* Partially alloc'ed */
struct rb_root skc_emergency_tree; /* Min sized objects */
spinlock_t skc_lock; /* Cache lock */
wait_queue_head_t skc_waitq; /* Allocation waiters */
uint64_t skc_slab_fail; /* Slab alloc failures */
uint64_t skc_slab_create; /* Slab creates */
uint64_t skc_slab_destroy; /* Slab destroys */
uint64_t skc_slab_total; /* Slab total current */
uint64_t skc_slab_alloc; /* Slab alloc current */
uint64_t skc_slab_max; /* Slab max historic */
uint64_t skc_obj_total; /* Obj total current */
uint64_t skc_obj_alloc; /* Obj alloc current */
uint64_t skc_obj_max; /* Obj max historic */
uint64_t skc_obj_deadlock; /* Obj emergency deadlocks */
uint64_t skc_obj_emergency; /* Obj emergency current */
uint64_t skc_obj_emergency_max; /* Obj emergency max */
} spl_kmem_cache_t;
#define kmem_cache_t spl_kmem_cache_t
extern spl_kmem_cache_t *spl_kmem_cache_create(char *name, size_t size,
size_t align, spl_kmem_ctor_t ctor, spl_kmem_dtor_t dtor,
spl_kmem_reclaim_t reclaim, void *priv, void *vmp, int flags);
extern void spl_kmem_cache_set_move(spl_kmem_cache_t *,
kmem_cbrc_t (*)(void *, void *, size_t, void *));
extern void spl_kmem_cache_destroy(spl_kmem_cache_t *skc);
extern void *spl_kmem_cache_alloc(spl_kmem_cache_t *skc, int flags);
extern void spl_kmem_cache_free(spl_kmem_cache_t *skc, void *obj);
extern void spl_kmem_cache_set_allocflags(spl_kmem_cache_t *skc, gfp_t flags);
extern void spl_kmem_cache_reap_now(spl_kmem_cache_t *skc, int count);
extern void spl_kmem_reap(void);
#define kmem_cache_create(name, size, align, ctor, dtor, rclm, priv, vmp, fl) \
spl_kmem_cache_create(name, size, align, ctor, dtor, rclm, priv, vmp, fl)
#define kmem_cache_set_move(skc, move) spl_kmem_cache_set_move(skc, move)
#define kmem_cache_destroy(skc) spl_kmem_cache_destroy(skc)
#define kmem_cache_alloc(skc, flags) spl_kmem_cache_alloc(skc, flags)
#define kmem_cache_free(skc, obj) spl_kmem_cache_free(skc, obj)
#define kmem_cache_reap_now(skc) \
spl_kmem_cache_reap_now(skc, skc->skc_reap)
#define kmem_reap() spl_kmem_reap()
/*
* The following functions are only available for internal use.
*/
extern int spl_kmem_cache_init(void);
extern void spl_kmem_cache_fini(void);
#endif /* _SPL_KMEM_CACHE_H */