POOL_CACHE(9)          NetBSD Kernel Developer's Manual          POOL_CACHE(9)

NAME
     pool_cache, pool_cache_init, pool_cache_destroy, pool_cache_get_paddr,
     pool_cache_get, pool_cache_put_paddr, pool_cache_put,
     pool_cache_destruct_object, pool_cache_invalidate -- resource-pool cache
     manager

SYNOPSIS
     #include <sys/pool.h>

     void
     pool_cache_init(struct pool_cache *pc, struct pool *pp,
         int (*ctor)(void *, void *, int), void (*dtor)(void *, void *),
         void *arg);

     void
     pool_cache_destroy(struct pool_cache *pc);

     void *
     pool_cache_get_paddr(struct pool_cache *pc, int flags, paddr_t *pap);

     void *
     pool_cache_get(struct pool_cache *pc, int flags);

     void
     pool_cache_put_paddr(struct pool_cache *pc, void *object, paddr_t pa);

     void
     pool_cache_put(struct pool_cache *pc, void *object);

     void
     pool_cache_destruct_object(struct pool_cache *pc, void *object);

     void
     pool_cache_invalidate(struct pool_cache *pc);

DESCRIPTION
     The pool_cache utility routines are provided to support caching of con-
     structed objects, similar to the Solaris SLAB allocator.  pool_cache uses
     pool(9) to allocate memory areas used for objects.  If the pool must be
     protected from interrupts, pool_cache routines expect to be called at the
     appropriate interrupt priority level.

FUNCTIONS
     pool_cache_init(pc, pp, ctor, dtor, arg)
              Initialize a pool cache pc.  The pool pp should be initialized
              by the caller in advance.  ctor and dtor are object constructor
              and destructor.  They can be NULL.

     pool_cache_destroy(pc)
              Destroy a pool cache pc.

     pool_cache_get_paddr(pc, flags, pap)
              Get an object from a pool cache pc.  If pap is not NULL, physi-
              cal address of the object or POOL_PADDR_INVALID will be returned
              via it.  flags will be passed to pool_get() function of the
              backing pool(9) and the object constructor specified when the
              pool cache is created by pool_cache_init().

     pool_cache_get(pc, flags)
              pool_cache_get() is the same as pool_cache_get_paddr() with NULL
              pap argument.  It's implemented as a macro.

     pool_cache_put_paddr(pc, object, pa)
              Put an object object back to the pool cache pc.  pa should be
              physical address of the object object or POOL_PADDR_INVALID.

     pool_cache_put(pc, object)
              pool_cache_put() is the same as pool_cache_put_paddr() with
              POOL_PADDR_INVALID pa argument.  It's implemented as a macro.

     pool_cache_destruct_object(pc, object)
              Force destruction of an object object and its release back into
              the pool.

     pool_cache_invalidate(pc)
              Invalidate a pool cache pc.  Destruct and release all of the
              cached objects.

CODE REFERENCES
     This section describes places within the NetBSD source tree where actual
     code implementing the pool_cache subsystem can be found.  All pathnames
     are relative to /usr/src.

     The pool_cache subsystem is implemented within the file
     sys/kern/subr_pool.c.

SEE ALSO
     intro(9), malloc(9), memoryallocators(9), pool(9)

NetBSD 4.0                     September 8, 2003                    NetBSD 4.0