bird/lib/resource.h
Maria Matejka f772afc525 Memory statistics split into Effective and Overhead
This feature is intended mostly for checking that BIRD's allocation
strategies don't consume much memory space. There are some cases where
withdrawing routes in a specific order lead to memory fragmentation and
this output should give the user at least a notion of how much memory is
actually used for data storage and how much memory is "just allocated"
or used for overhead.

Also raising the "system allocator overhead estimation" from 8 to 16
bytes; it is probably even more. I've found 16 as a local minimum in
best scenarios among reachable machines. I couldn't find any reasonable
method to estimate this value when BIRD starts up.

This commit also fixes the inaccurate computation of memory overhead for
slabs where the "system allocater overhead estimation" was improperly
added to the size of mmap-ed memory.
2021-11-27 22:54:15 +01:00

139 lines
3.9 KiB
C

/*
* BIRD Resource Manager
*
* (c) 1998--1999 Martin Mares <mj@ucw.cz>
* (c) 2021 Maria Matejka <mq@jmq.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_RESOURCE_H_
#define _BIRD_RESOURCE_H_
#include "lib/lists.h"
struct resmem {
size_t effective; /* Memory actually used for data storage */
size_t overhead; /* Overhead memory imposed by allocator strategies */
};
/* Resource */
typedef struct resource {
node n; /* Inside resource pool */
struct resclass *class; /* Resource class */
} resource;
/* Resource class */
struct resclass {
char *name; /* Resource class name */
unsigned size; /* Standard size of single resource */
void (*free)(resource *); /* Freeing function */
void (*dump)(resource *); /* Dump to debug output */
resource *(*lookup)(resource *, unsigned long); /* Look up address (only for debugging) */
struct resmem (*memsize)(resource *); /* Return size of memory used by the resource, may be NULL */
};
/* Estimate of system allocator overhead per item, for memory consumtion stats */
#define ALLOC_OVERHEAD 16
/* Generic resource manipulation */
typedef struct pool pool;
void resource_init(void);
pool *rp_new(pool *, const char *); /* Create new pool */
void rfree(void *); /* Free single resource */
void rdump(void *); /* Dump to debug output */
struct resmem rmemsize(void *res); /* Return size of memory used by the resource */
void rlookup(unsigned long); /* Look up address (only for debugging) */
void rmove(void *, pool *); /* Move to a different pool */
void *ralloc(pool *, struct resclass *);
extern pool root_pool;
/* Normal memory blocks */
void *mb_alloc(pool *, unsigned size);
void *mb_allocz(pool *, unsigned size);
void *mb_realloc(void *m, unsigned size);
void mb_move(void *, pool *);
void mb_free(void *);
/* Memory pools with linear allocation */
typedef struct linpool linpool;
typedef struct lp_state {
void *current, *large;
byte *ptr;
} lp_state;
linpool *lp_new(pool *, unsigned blk);
void *lp_alloc(linpool *, unsigned size); /* Aligned */
void *lp_allocu(linpool *, unsigned size); /* Unaligned */
void *lp_allocz(linpool *, unsigned size); /* With clear */
void lp_flush(linpool *); /* Free everything, but leave linpool */
void lp_save(linpool *m, lp_state *p); /* Save state */
void lp_restore(linpool *m, lp_state *p); /* Restore state */
extern const int lp_chunk_size;
#define LP_GAS 1024
#define LP_GOOD_SIZE(x) (((x + LP_GAS - 1) & (~(LP_GAS - 1))) - lp_chunk_size)
#define lp_new_default(p) lp_new(p, LP_GOOD_SIZE(LP_GAS*4))
/* Slabs */
typedef struct slab slab;
slab *sl_new(pool *, unsigned size);
void *sl_alloc(slab *);
void *sl_allocz(slab *);
void sl_free(slab *, void *);
/*
* Low-level memory allocation functions, please don't use
* outside resource manager and possibly sysdep code.
*/
void buffer_realloc(void **buf, unsigned *size, unsigned need, unsigned item_size);
/* Allocator of whole pages; for use in slabs and other high-level allocators. */
u64 get_page_size(void);
void *alloc_page(void);
void free_page(void *);
extern uint pages_kept;
#ifdef HAVE_LIBDMALLOC
/*
* The standard dmalloc macros tend to produce lots of namespace
* conflicts and we use only xmalloc, xrealloc and xfree, so we
* can define the stubs ourselves.
*/
#define DMALLOC_DISABLE
#include <dmalloc.h>
#define xmalloc(size) \
dmalloc_malloc(__FILE__, __LINE__, (size), DMALLOC_FUNC_MALLOC, 0, 1)
#define xrealloc(ptr, size) \
dmalloc_realloc(__FILE__, __LINE__, (ptr), (size), DMALLOC_FUNC_REALLOC, 1)
#define xfree(ptr) \
dmalloc_free(__FILE__, __LINE__, (ptr), DMALLOC_FUNC_FREE)
#else
/*
* Unfortunately, several libraries we might want to link to define
* their own xmalloc and we don't want to interfere with them, hence
* the renaming.
*/
#define xmalloc bird_xmalloc
#define xrealloc bird_xrealloc
void *xmalloc(unsigned);
void *xrealloc(void *, unsigned);
#define xfree(x) free(x)
#endif
#endif