freebsd-dev/contrib/sendmail/libsm/rpool.c
2002-06-11 21:12:04 +00:00

494 lines
11 KiB
C

/*
* Copyright (c) 2000-2002 Sendmail, Inc. and its suppliers.
* All rights reserved.
*
* By using this file, you agree to the terms and conditions set
* forth in the LICENSE file which can be found at the top level of
* the sendmail distribution.
*/
#include <sm/gen.h>
SM_RCSID("@(#)$Id: rpool.c,v 1.24 2002/01/11 21:54:43 ca Exp $")
/*
** resource pools
** For documentation, see rpool.html
*/
#include <sm/exc.h>
#include <sm/heap.h>
#include <sm/rpool.h>
#include <sm/varargs.h>
#include <sm/conf.h>
#if _FFR_PERF_RPOOL
# include <syslog.h>
#endif /* _FFR_PERF_RPOOL */
const char SmRpoolMagic[] = "sm_rpool";
typedef union
{
SM_POOLLINK_T link;
char align[SM_ALIGN_SIZE];
} SM_POOLHDR_T;
/*
** Tune this later
*/
#define POOLSIZE 4096
#define BIG_OBJECT_RATIO 10
/*
** SM_RPOOL_ALLOCBLOCK_X -- allocate a new block for an rpool.
**
** Parameters:
** rpool -- rpool to which the block should be added.
** size -- size of block.
**
** Returns:
** Pointer to block.
**
** Exceptions:
** F:sm_heap -- out of memory
*/
static char *
sm_rpool_allocblock_x(rpool, size)
SM_RPOOL_T *rpool;
size_t size;
{
SM_POOLLINK_T *p;
p = sm_malloc_x(sizeof(SM_POOLHDR_T) + size);
p->sm_pnext = rpool->sm_pools;
rpool->sm_pools = p;
return (char*) p + sizeof(SM_POOLHDR_T);
}
/*
** SM_RPOOL_ALLOCBLOCK -- allocate a new block for an rpool.
**
** Parameters:
** rpool -- rpool to which the block should be added.
** size -- size of block.
**
** Returns:
** Pointer to block, NULL on failure.
*/
static char *
sm_rpool_allocblock(rpool, size)
SM_RPOOL_T *rpool;
size_t size;
{
SM_POOLLINK_T *p;
p = sm_malloc(sizeof(SM_POOLHDR_T) + size);
if (p == NULL)
return NULL;
p->sm_pnext = rpool->sm_pools;
rpool->sm_pools = p;
return (char*) p + sizeof(SM_POOLHDR_T);
}
/*
** SM_RPOOL_MALLOC_TAGGED_X -- allocate memory from rpool
**
** Parameters:
** rpool -- rpool from which memory should be allocated;
** can be NULL, use sm_malloc() then.
** size -- size of block.
** file -- filename.
** line -- line number in file.
** group -- heap group for debugging.
**
** Returns:
** Pointer to block.
**
** Exceptions:
** F:sm_heap -- out of memory
**
** Notice: XXX
** if size == 0 and the rpool is new (no memory
** allocated yet) NULL is returned!
** We could solve this by
** - wasting 1 byte (size < avail)
** - checking for rpool->sm_poolptr != NULL
** - not asking for 0 sized buffer
*/
void *
#if SM_HEAP_CHECK
sm_rpool_malloc_tagged_x(rpool, size, file, line, group)
SM_RPOOL_T *rpool;
size_t size;
char *file;
int line;
int group;
#else /* SM_HEAP_CHECK */
sm_rpool_malloc_x(rpool, size)
SM_RPOOL_T *rpool;
size_t size;
#endif /* SM_HEAP_CHECK */
{
char *ptr;
if (rpool == NULL)
return sm_malloc_tagged_x(size, file, line, group);
/* Ensure that size is properly aligned. */
if (size & SM_ALIGN_BITS)
size = (size & ~SM_ALIGN_BITS) + SM_ALIGN_SIZE;
/* The common case. This is optimized for speed. */
if (size <= rpool->sm_poolavail)
{
ptr = rpool->sm_poolptr;
rpool->sm_poolptr += size;
rpool->sm_poolavail -= size;
return ptr;
}
/*
** The slow case: we need to call malloc.
** The SM_REQUIRE assertion is deferred until now, for speed.
** That's okay: we set rpool->sm_poolavail to 0 when we free an rpool,
** so the common case code won't be triggered on a dangling pointer.
*/
SM_REQUIRE(rpool->sm_magic == SmRpoolMagic);
/*
** If size > sm_poolsize, then malloc a new block especially for
** this request. Future requests will be allocated from the
** current pool.
**
** What if the current pool is mostly unallocated, and the current
** request is larger than the available space, but < sm_poolsize?
** If we discard the current pool, and start allocating from a new
** pool, then we will be wasting a lot of space. For this reason,
** we malloc a block just for the current request if size >
** sm_bigobjectsize, where sm_bigobjectsize <= sm_poolsize.
** Thus, the most space that we will waste at the end of a pool
** is sm_bigobjectsize - 1.
*/
if (size > rpool->sm_bigobjectsize)
{
#if _FFR_PERF_RPOOL
++rpool->sm_nbigblocks;
#endif /* _FFR_PERF_RPOOL */
return sm_rpool_allocblock_x(rpool, size);
}
SM_ASSERT(rpool->sm_bigobjectsize <= rpool->sm_poolsize);
ptr = sm_rpool_allocblock_x(rpool, rpool->sm_poolsize);
rpool->sm_poolptr = ptr + size;
rpool->sm_poolavail = rpool->sm_poolsize - size;
#if _FFR_PERF_RPOOL
++rpool->sm_npools;
#endif /* _FFR_PERF_RPOOL */
return ptr;
}
/*
** SM_RPOOL_MALLOC_TAGGED -- allocate memory from rpool
**
** Parameters:
** rpool -- rpool from which memory should be allocated;
** can be NULL, use sm_malloc() then.
** size -- size of block.
** file -- filename.
** line -- line number in file.
** group -- heap group for debugging.
**
** Returns:
** Pointer to block, NULL on failure.
**
** Notice: XXX
** if size == 0 and the rpool is new (no memory
** allocated yet) NULL is returned!
** We could solve this by
** - wasting 1 byte (size < avail)
** - checking for rpool->sm_poolptr != NULL
** - not asking for 0 sized buffer
*/
void *
#if SM_HEAP_CHECK
sm_rpool_malloc_tagged(rpool, size, file, line, group)
SM_RPOOL_T *rpool;
size_t size;
char *file;
int line;
int group;
#else /* SM_HEAP_CHECK */
sm_rpool_malloc(rpool, size)
SM_RPOOL_T *rpool;
size_t size;
#endif /* SM_HEAP_CHECK */
{
char *ptr;
if (rpool == NULL)
return sm_malloc_tagged(size, file, line, group);
/* Ensure that size is properly aligned. */
if (size & SM_ALIGN_BITS)
size = (size & ~SM_ALIGN_BITS) + SM_ALIGN_SIZE;
/* The common case. This is optimized for speed. */
if (size <= rpool->sm_poolavail)
{
ptr = rpool->sm_poolptr;
rpool->sm_poolptr += size;
rpool->sm_poolavail -= size;
return ptr;
}
/*
** The slow case: we need to call malloc.
** The SM_REQUIRE assertion is deferred until now, for speed.
** That's okay: we set rpool->sm_poolavail to 0 when we free an rpool,
** so the common case code won't be triggered on a dangling pointer.
*/
SM_REQUIRE(rpool->sm_magic == SmRpoolMagic);
/*
** If size > sm_poolsize, then malloc a new block especially for
** this request. Future requests will be allocated from the
** current pool.
**
** What if the current pool is mostly unallocated, and the current
** request is larger than the available space, but < sm_poolsize?
** If we discard the current pool, and start allocating from a new
** pool, then we will be wasting a lot of space. For this reason,
** we malloc a block just for the current request if size >
** sm_bigobjectsize, where sm_bigobjectsize <= sm_poolsize.
** Thus, the most space that we will waste at the end of a pool
** is sm_bigobjectsize - 1.
*/
if (size > rpool->sm_bigobjectsize)
{
#if _FFR_PERF_RPOOL
++rpool->sm_nbigblocks;
#endif /* _FFR_PERF_RPOOL */
return sm_rpool_allocblock(rpool, size);
}
SM_ASSERT(rpool->sm_bigobjectsize <= rpool->sm_poolsize);
ptr = sm_rpool_allocblock(rpool, rpool->sm_poolsize);
if (ptr == NULL)
return NULL;
rpool->sm_poolptr = ptr + size;
rpool->sm_poolavail = rpool->sm_poolsize - size;
#if _FFR_PERF_RPOOL
++rpool->sm_npools;
#endif /* _FFR_PERF_RPOOL */
return ptr;
}
/*
** SM_RPOOL_NEW_X -- create a new rpool.
**
** Parameters:
** parent -- pointer to parent rpool, can be NULL.
**
** Returns:
** Pointer to new rpool.
*/
SM_RPOOL_T *
sm_rpool_new_x(parent)
SM_RPOOL_T *parent;
{
SM_RPOOL_T *rpool;
rpool = sm_malloc_x(sizeof(SM_RPOOL_T));
if (parent == NULL)
rpool->sm_parentlink = NULL;
else
{
SM_TRY
rpool->sm_parentlink = sm_rpool_attach_x(parent,
(SM_RPOOL_RFREE_T) sm_rpool_free,
(void *) rpool);
SM_EXCEPT(exc, "*")
sm_free(rpool);
sm_exc_raise_x(exc);
SM_END_TRY
}
rpool->sm_magic = SmRpoolMagic;
rpool->sm_poolsize = POOLSIZE - sizeof(SM_POOLHDR_T);
rpool->sm_bigobjectsize = rpool->sm_poolsize / BIG_OBJECT_RATIO;
rpool->sm_poolptr = NULL;
rpool->sm_poolavail = 0;
rpool->sm_pools = NULL;
rpool->sm_rptr = NULL;
rpool->sm_ravail = 0;
rpool->sm_rlists = NULL;
#if _FFR_PERF_RPOOL
rpool->sm_nbigblocks = 0;
rpool->sm_npools = 0;
#endif /* _FFR_PERF_RPOOL */
return rpool;
}
/*
** SM_RPOOL_SETSIZES -- set sizes for rpool.
**
** Parameters:
** poolsize -- size of a single rpool block.
** bigobjectsize -- if this size is exceeded, an individual
** block is allocated (must be less or equal poolsize).
**
** Returns:
** none.
*/
void
sm_rpool_setsizes(rpool, poolsize, bigobjectsize)
SM_RPOOL_T *rpool;
size_t poolsize;
size_t bigobjectsize;
{
SM_REQUIRE(poolsize >= bigobjectsize);
if (poolsize == 0)
poolsize = POOLSIZE - sizeof(SM_POOLHDR_T);
if (bigobjectsize == 0)
bigobjectsize = poolsize / BIG_OBJECT_RATIO;
rpool->sm_poolsize = poolsize;
rpool->sm_bigobjectsize = bigobjectsize;
}
/*
** SM_RPOOL_FREE -- free an rpool and release all of its resources.
**
** Parameters:
** rpool -- rpool to free.
**
** Returns:
** none.
*/
void
sm_rpool_free(rpool)
SM_RPOOL_T *rpool;
{
SM_RLIST_T *rl, *rnext;
SM_RESOURCE_T *r, *rmax;
SM_POOLLINK_T *pp, *pnext;
if (rpool == NULL)
return;
/*
** It's important to free the resources before the memory pools,
** because the resource free functions might modify the contents
** of the memory pools.
*/
rl = rpool->sm_rlists;
if (rl != NULL)
{
rmax = rpool->sm_rptr;
for (;;)
{
for (r = rl->sm_rvec; r < rmax; ++r)
{
if (r->sm_rfree != NULL)
r->sm_rfree(r->sm_rcontext);
}
rnext = rl->sm_rnext;
sm_free(rl);
if (rnext == NULL)
break;
rl = rnext;
rmax = &rl->sm_rvec[SM_RLIST_MAX];
}
}
/*
** Now free the memory pools.
*/
for (pp = rpool->sm_pools; pp != NULL; pp = pnext)
{
pnext = pp->sm_pnext;
sm_free(pp);
}
/*
** Disconnect rpool from its parent.
*/
if (rpool->sm_parentlink != NULL)
*rpool->sm_parentlink = NULL;
/*
** Setting these fields to zero means that any future to attempt
** to use the rpool after it is freed will cause an assertion failure.
*/
rpool->sm_magic = NULL;
rpool->sm_poolavail = 0;
rpool->sm_ravail = 0;
#if _FFR_PERF_RPOOL
if (rpool->sm_nbigblocks > 0 || rpool->sm_npools > 1)
syslog(LOG_NOTICE,
"perf: rpool=%lx, sm_nbigblocks=%d, sm_npools=%d",
(long) rpool, rpool->sm_nbigblocks, rpool->sm_npools);
rpool->sm_nbigblocks = 0;
rpool->sm_npools = 0;
#endif /* _FFR_PERF_RPOOL */
sm_free(rpool);
}
/*
** SM_RPOOL_ATTACH_X -- attach a resource to an rpool.
**
** Parameters:
** rpool -- rpool to which resource should be attached.
** rfree -- function to call when rpool is freed.
** rcontext -- argument for function to call when rpool is freed.
**
** Returns:
** Pointer to allocated function.
**
** Exceptions:
** F:sm_heap -- out of memory
*/
SM_RPOOL_ATTACH_T
sm_rpool_attach_x(rpool, rfree, rcontext)
SM_RPOOL_T *rpool;
SM_RPOOL_RFREE_T rfree;
void *rcontext;
{
SM_RLIST_T *rl;
SM_RPOOL_ATTACH_T a;
SM_REQUIRE_ISA(rpool, SmRpoolMagic);
if (rpool->sm_ravail == 0)
{
rl = sm_malloc_x(sizeof(SM_RLIST_T));
rl->sm_rnext = rpool->sm_rlists;
rpool->sm_rlists = rl;
rpool->sm_rptr = rl->sm_rvec;
rpool->sm_ravail = SM_RLIST_MAX;
}
a = &rpool->sm_rptr->sm_rfree;
rpool->sm_rptr->sm_rfree = rfree;
rpool->sm_rptr->sm_rcontext = rcontext;
++rpool->sm_rptr;
--rpool->sm_ravail;
return a;
}