include/os/linux/spl/sys/kmem_cache.h

   1 /*
   2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
   3  *  Copyright (C) 2007 The Regents of the University of California.
   4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
   5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
   6  *  UCRL-CODE-235197
   7  *
   8  *  This file is part of the SPL, Solaris Porting Layer.
   9  *
  10  *  The SPL is free software; you can redistribute it and/or modify it
  11  *  under the terms of the GNU General Public License as published by the
  12  *  Free Software Foundation; either version 2 of the License, or (at your
  13  *  option) any later version.
  14  *
  15  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
  16  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18  *  for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #ifndef _SPL_KMEM_CACHE_H
  25 #define _SPL_KMEM_CACHE_H
  26
  27 #include <sys/taskq.h>
  28
  29 /*
  30  * Slab allocation interfaces.  The SPL slab differs from the standard
  31  * Linux SLAB or SLUB primarily in that each cache may be backed by slabs
  32  * allocated from the physical or virtual memory address space.  The virtual
  33  * slabs allow for good behavior when allocation large objects of identical
  34  * size.  This slab implementation also supports both constructors and
  35  * destructors which the Linux slab does not.
  36  */
  37 typedef enum kmc_bit {
  38         KMC_BIT_NODEBUG         = 1,    /* Default behavior */
  39         KMC_BIT_KVMEM           = 7,    /* Use kvmalloc linux allocator  */
  40         KMC_BIT_SLAB            = 8,    /* Use Linux slab cache */
  41         KMC_BIT_DEADLOCKED      = 14,   /* Deadlock detected */
  42         KMC_BIT_GROWING         = 15,   /* Growing in progress */
  43         KMC_BIT_REAPING         = 16,   /* Reaping in progress */
  44         KMC_BIT_DESTROY         = 17,   /* Destroy in progress */
  45         KMC_BIT_TOTAL           = 18,   /* Proc handler helper bit */
  46         KMC_BIT_ALLOC           = 19,   /* Proc handler helper bit */
  47         KMC_BIT_MAX             = 20,   /* Proc handler helper bit */
  48 } kmc_bit_t;
  49
  50 /* kmem move callback return values */
  51 typedef enum kmem_cbrc {
  52         KMEM_CBRC_YES           = 0,    /* Object moved */
  53         KMEM_CBRC_NO            = 1,    /* Object not moved */
  54         KMEM_CBRC_LATER         = 2,    /* Object not moved, try again later */
  55         KMEM_CBRC_DONT_NEED     = 3,    /* Neither object is needed */
  56         KMEM_CBRC_DONT_KNOW     = 4,    /* Object unknown */
  57 } kmem_cbrc_t;
  58
  59 #define KMC_NODEBUG             (1 << KMC_BIT_NODEBUG)
  60 #define KMC_KVMEM               (1 << KMC_BIT_KVMEM)
  61 #define KMC_SLAB                (1 << KMC_BIT_SLAB)
  62 #define KMC_DEADLOCKED          (1 << KMC_BIT_DEADLOCKED)
  63 #define KMC_GROWING             (1 << KMC_BIT_GROWING)
  64 #define KMC_REAPING             (1 << KMC_BIT_REAPING)
  65 #define KMC_DESTROY             (1 << KMC_BIT_DESTROY)
  66 #define KMC_TOTAL               (1 << KMC_BIT_TOTAL)
  67 #define KMC_ALLOC               (1 << KMC_BIT_ALLOC)
  68 #define KMC_MAX                 (1 << KMC_BIT_MAX)
  69
  70 #define KMC_REAP_CHUNK          INT_MAX
  71 #define KMC_DEFAULT_SEEKS       1
  72
  73 #define KMC_RECLAIM_ONCE        0x1     /* Force a single shrinker pass */
  74
  75 extern struct list_head spl_kmem_cache_list;
  76 extern struct rw_semaphore spl_kmem_cache_sem;
  77
  78 #define SKM_MAGIC                       0x2e2e2e2e
  79 #define SKO_MAGIC                       0x20202020
  80 #define SKS_MAGIC                       0x22222222
  81 #define SKC_MAGIC                       0x2c2c2c2c
  82
  83 #define SPL_KMEM_CACHE_OBJ_PER_SLAB     8       /* Target objects per slab */
  84 #define SPL_KMEM_CACHE_ALIGN            8       /* Default object alignment */
  85 #ifdef _LP64
  86 #define SPL_KMEM_CACHE_MAX_SIZE         32      /* Max slab size in MB */
  87 #else
  88 #define SPL_KMEM_CACHE_MAX_SIZE         4       /* Max slab size in MB */
  89 #endif
  90
  91 #define SPL_MAX_ORDER                   (MAX_ORDER - 3)
  92 #define SPL_MAX_ORDER_NR_PAGES          (1 << (SPL_MAX_ORDER - 1))
  93
  94 #ifdef CONFIG_SLUB
  95 #define SPL_MAX_KMEM_CACHE_ORDER        PAGE_ALLOC_COSTLY_ORDER
  96 #define SPL_MAX_KMEM_ORDER_NR_PAGES     (1 << (SPL_MAX_KMEM_CACHE_ORDER - 1))
  97 #else
  98 #define SPL_MAX_KMEM_ORDER_NR_PAGES     (KMALLOC_MAX_SIZE >> PAGE_SHIFT)
  99 #endif
 100
 101 #define POINTER_IS_VALID(p)             0       /* Unimplemented */
 102 #define POINTER_INVALIDATE(pp)                  /* Unimplemented */
 103
 104 typedef int (*spl_kmem_ctor_t)(void *, void *, int);
 105 typedef void (*spl_kmem_dtor_t)(void *, void *);
 106
 107 typedef struct spl_kmem_magazine {
 108         uint32_t                skm_magic;      /* Sanity magic */
 109         uint32_t                skm_avail;      /* Available objects */
 110         uint32_t                skm_size;       /* Magazine size */
 111         uint32_t                skm_refill;     /* Batch refill size */
 112         struct spl_kmem_cache   *skm_cache;     /* Owned by cache */
 113         unsigned int            skm_cpu;        /* Owned by cpu */
 114         void                    *skm_objs[0];   /* Object pointers */
 115 } spl_kmem_magazine_t;
 116
 117 typedef struct spl_kmem_obj {
 118         uint32_t                sko_magic;      /* Sanity magic */
 119         void                    *sko_addr;      /* Buffer address */
 120         struct spl_kmem_slab    *sko_slab;      /* Owned by slab */
 121         struct list_head        sko_list;       /* Free object list linkage */
 122 } spl_kmem_obj_t;
 123
 124 typedef struct spl_kmem_slab {
 125         uint32_t                sks_magic;      /* Sanity magic */
 126         uint32_t                sks_objs;       /* Objects per slab */
 127         struct spl_kmem_cache   *sks_cache;     /* Owned by cache */
 128         struct list_head        sks_list;       /* Slab list linkage */
 129         struct list_head        sks_free_list;  /* Free object list */
 130         unsigned long           sks_age;        /* Last modify jiffie */
 131         uint32_t                sks_ref;        /* Ref count used objects */
 132 } spl_kmem_slab_t;
 133
 134 typedef struct spl_kmem_alloc {
 135         struct spl_kmem_cache   *ska_cache;     /* Owned by cache */
 136         int                     ska_flags;      /* Allocation flags */
 137         taskq_ent_t             ska_tqe;        /* Task queue entry */
 138 } spl_kmem_alloc_t;
 139
 140 typedef struct spl_kmem_emergency {
 141         struct rb_node          ske_node;       /* Emergency tree linkage */
 142         unsigned long           ske_obj;        /* Buffer address */
 143 } spl_kmem_emergency_t;
 144
 145 typedef struct spl_kmem_cache {
 146         uint32_t                skc_magic;      /* Sanity magic */
 147         uint32_t                skc_name_size;  /* Name length */
 148         char                    *skc_name;      /* Name string */
 149         spl_kmem_magazine_t     **skc_mag;      /* Per-CPU warm cache */
 150         uint32_t                skc_mag_size;   /* Magazine size */
 151         uint32_t                skc_mag_refill; /* Magazine refill count */
 152         spl_kmem_ctor_t         skc_ctor;       /* Constructor */
 153         spl_kmem_dtor_t         skc_dtor;       /* Destructor */
 154         void                    *skc_private;   /* Private data */
 155         void                    *skc_vmp;       /* Unused */
 156         struct kmem_cache       *skc_linux_cache; /* Linux slab cache if used */
 157         unsigned long           skc_flags;      /* Flags */
 158         uint32_t                skc_obj_size;   /* Object size */
 159         uint32_t                skc_obj_align;  /* Object alignment */
 160         uint32_t                skc_slab_objs;  /* Objects per slab */
 161         uint32_t                skc_slab_size;  /* Slab size */
 162         atomic_t                skc_ref;        /* Ref count callers */
 163         taskqid_t               skc_taskqid;    /* Slab reclaim task */
 164         struct list_head        skc_list;       /* List of caches linkage */
 165         struct list_head        skc_complete_list; /* Completely alloc'ed */
 166         struct list_head        skc_partial_list;  /* Partially alloc'ed */
 167         struct rb_root          skc_emergency_tree; /* Min sized objects */
 168         spinlock_t              skc_lock;       /* Cache lock */
 169         spl_wait_queue_head_t   skc_waitq;      /* Allocation waiters */
 170         uint64_t                skc_slab_fail;  /* Slab alloc failures */
 171         uint64_t                skc_slab_create;  /* Slab creates */
 172         uint64_t                skc_slab_destroy; /* Slab destroys */
 173         uint64_t                skc_slab_total; /* Slab total current */
 174         uint64_t                skc_slab_alloc; /* Slab alloc current */
 175         uint64_t                skc_slab_max;   /* Slab max historic  */
 176         uint64_t                skc_obj_total;  /* Obj total current */
 177         uint64_t                skc_obj_alloc;  /* Obj alloc current */
 178         struct percpu_counter   skc_linux_alloc;   /* Linux-backed Obj alloc  */
 179         uint64_t                skc_obj_max;    /* Obj max historic */
 180         uint64_t                skc_obj_deadlock;  /* Obj emergency deadlocks */
 181         uint64_t                skc_obj_emergency; /* Obj emergency current */
 182         uint64_t                skc_obj_emergency_max; /* Obj emergency max */
 183 } spl_kmem_cache_t;
 184 #define kmem_cache_t            spl_kmem_cache_t
 185
 186 extern spl_kmem_cache_t *spl_kmem_cache_create(char *name, size_t size,
 187     size_t align, spl_kmem_ctor_t ctor, spl_kmem_dtor_t dtor,
 188     void *reclaim, void *priv, void *vmp, int flags);
 189 extern void spl_kmem_cache_set_move(spl_kmem_cache_t *,
 190     kmem_cbrc_t (*)(void *, void *, size_t, void *));
 191 extern void spl_kmem_cache_destroy(spl_kmem_cache_t *skc);
 192 extern void *spl_kmem_cache_alloc(spl_kmem_cache_t *skc, int flags);
 193 extern void spl_kmem_cache_free(spl_kmem_cache_t *skc, void *obj);
 194 extern void spl_kmem_cache_set_allocflags(spl_kmem_cache_t *skc, gfp_t flags);
 195 extern void spl_kmem_cache_reap_now(spl_kmem_cache_t *skc);
 196 extern void spl_kmem_reap(void);
 197 extern uint64_t spl_kmem_cache_inuse(kmem_cache_t *cache);
 198 extern uint64_t spl_kmem_cache_entry_size(kmem_cache_t *cache);
 199
 200 #define kmem_cache_create(name, size, align, ctor, dtor, rclm, priv, vmp, fl) \
 201     spl_kmem_cache_create(name, size, align, ctor, dtor, rclm, priv, vmp, fl)
 202 #define kmem_cache_set_move(skc, move)  spl_kmem_cache_set_move(skc, move)
 203 #define kmem_cache_destroy(skc)         spl_kmem_cache_destroy(skc)
 204 #define kmem_cache_alloc(skc, flags)    spl_kmem_cache_alloc(skc, flags)
 205 #define kmem_cache_free(skc, obj)       spl_kmem_cache_free(skc, obj)
 206 #define kmem_cache_reap_now(skc)        spl_kmem_cache_reap_now(skc)
 207 #define kmem_reap()                     spl_kmem_reap()
 208
 209 /*
 210  * The following functions are only available for internal use.
 211  */
 212 extern int spl_kmem_cache_init(void);
 213 extern void spl_kmem_cache_fini(void);
 214
 215 #endif  /* _SPL_KMEM_CACHE_H */