* UCW Library -- Memory Pools (One-Time Allocation)
*
* (c) 1997--2001 Martin Mares <mj@ucw.cz>
+ * (c) 2007 Pavel Charvat <pchar@ucw.cz>
*
* This software may be freely distributed and used according to the terms
* of the GNU Lesser General Public License.
*/
+#undef LOCAL_DEBUG
+
#include "lib/lib.h"
#include "lib/mempool.h"
#include <string.h>
-struct memchunk {
- struct memchunk *next;
- byte data[0];
+#define MP_CHUNK_TAIL ALIGN_TO(sizeof(struct mempool_chunk), CPU_STRUCT_ALIGN)
+#define MP_SIZE_MAX (~0U - MP_CHUNK_TAIL - CPU_PAGE_SIZE)
+
+struct mempool_chunk {
+ struct mempool_chunk *next;
+ uns size;
};
+static uns
+mp_align_size(uns size)
+{
+#ifdef POOL_IS_MMAP
+ return ALIGN_TO(size + MP_CHUNK_TAIL, CPU_PAGE_SIZE) - MP_CHUNK_TAIL;
+#else
+ return ALIGN_TO(size, CPU_STRUCT_ALIGN);
+#endif
+}
+
+void
+mp_init(struct mempool *pool, uns chunk_size)
+{
+ chunk_size = mp_align_size(MAX(sizeof(struct mempool), chunk_size));
+ *pool = (struct mempool) {
+ .chunk_size = chunk_size,
+ .threshold = chunk_size >> 1,
+ .last_big = &pool->last_big };
+}
+
+static void *
+mp_new_big_chunk(uns size)
+{
+ struct mempool_chunk *chunk;
+ chunk = xmalloc(size + MP_CHUNK_TAIL) + size;
+ chunk->size = size;
+ return chunk;
+}
+
+static void
+mp_free_big_chunk(struct mempool_chunk *chunk)
+{
+ xfree((void *)chunk - chunk->size);
+}
+
+static void *
+mp_new_chunk(uns size)
+{
+#ifdef POOL_IS_MMAP
+ struct mempool_chunk *chunk;
+ chunk = page_alloc(size + MP_CHUNK_TAIL) + size;
+ chunk->size = size;
+ return chunk;
+#else
+ return mp_new_big_chunk(size);
+#endif
+}
+
+static void
+mp_free_chunk(struct mempool_chunk *chunk)
+{
+#ifdef POOL_IS_MMAP
+ page_free((void *)chunk - chunk->size, chunk->size + MP_CHUNK_TAIL);
+#else
+ mp_free_big_chunk(chunk);
+#endif
+}
+
struct mempool *
-mp_new(uns size)
+mp_new(uns chunk_size)
{
- struct mempool *p = xmalloc(sizeof(struct mempool));
+ chunk_size = mp_align_size(MAX(sizeof(struct mempool), chunk_size));
+ struct mempool_chunk *chunk = mp_new_chunk(chunk_size);
+ struct mempool *pool = (void *)chunk - chunk_size;
+ DBG("Creating mempool %p with %u bytes long chunks", pool, chunk_size);
+ chunk->next = NULL;
+ *pool = (struct mempool) {
+ .state = { .free = { chunk_size - sizeof(*pool) }, .last = { chunk } },
+ .chunk_size = chunk_size,
+ .threshold = chunk_size >> 1,
+ .last_big = &pool->last_big };
+ return pool;
+}
- size -= sizeof(struct memchunk);
- p->free = p->last = NULL;
- p->first = p->current = p->first_large = NULL;
- p->plast = &p->first;
- p->chunk_size = size;
- p->threshold = size / 3;
- return p;
+static void
+mp_free_chain(struct mempool_chunk *chunk)
+{
+ while (chunk)
+ {
+ struct mempool_chunk *next = chunk->next;
+ mp_free_chunk(chunk);
+ chunk = next;
+ }
+}
+
+static void
+mp_free_big_chain(struct mempool_chunk *chunk)
+{
+ while (chunk)
+ {
+ struct mempool_chunk *next = chunk->next;
+ mp_free_big_chunk(chunk);
+ chunk = next;
+ }
}
void
-mp_delete(struct mempool *p)
+mp_delete(struct mempool *pool)
{
- struct memchunk *c, *d;
+ DBG("Deleting mempool %p", pool);
+ mp_free_big_chain(pool->state.last[1]);
+ mp_free_chain(pool->unused);
+ mp_free_chain(pool->state.last[0]); // can contain the mempool structure
+}
- for(d=p->first; d; d = c)
+void
+mp_flush(struct mempool *pool)
+{
+ mp_free_big_chain(pool->state.last[1]);
+ struct mempool_chunk *chunk, *next;
+ for (chunk = pool->state.last[0]; chunk && (void *)chunk - chunk->size != pool; chunk = next)
{
- c = d->next;
- xfree(d);
+ next = chunk->next;
+ chunk->next = pool->unused;
+ pool->unused = chunk;
}
- for(d=p->first_large; d; d = c)
+ pool->state.last[0] = chunk;
+ pool->state.free[0] = chunk ? chunk->size - sizeof(*pool) : 0;
+ pool->state.last[1] = NULL;
+ pool->state.free[1] = 0;
+ pool->state.next = NULL;
+ pool->last_big = &pool->last_big;
+}
+
+static void
+mp_stats_chain(struct mempool_chunk *chunk, struct mempool_stats *stats, uns idx)
+{
+ while (chunk)
{
- c = d->next;
- xfree(d);
+ stats->chain_size[idx] += chunk->size + sizeof(*chunk);
+ stats->chain_count[idx]++;
+ chunk = chunk->next;
}
- xfree(p);
+ stats->total_size += stats->chain_size[idx];
}
void
-mp_flush(struct mempool *p)
+mp_stats(struct mempool *pool, struct mempool_stats *stats)
{
- struct memchunk *c;
+ bzero(stats, sizeof(*stats));
+ mp_stats_chain(pool->state.last[0], stats, 0);
+ mp_stats_chain(pool->state.last[1], stats, 1);
+ mp_stats_chain(pool->unused, stats, 2);
+}
- p->free = p->last = NULL;
- p->current = p->first;
- while (c = p->first_large)
+void *
+mp_alloc_internal(struct mempool *pool, uns size)
+{
+ struct mempool_chunk *chunk;
+ if (size <= pool->threshold)
+ {
+ pool->idx = 0;
+ if (pool->unused)
+ {
+ chunk = pool->unused;
+ pool->unused = chunk->next;
+ }
+ else
+ chunk = mp_new_chunk(pool->chunk_size);
+ chunk->next = pool->state.last[0];
+ pool->state.last[0] = chunk;
+ pool->state.free[0] = pool->chunk_size - size;
+ return (void *)chunk - pool->chunk_size;
+ }
+ else if (likely(size <= MP_SIZE_MAX))
{
- p->first_large = c->next;
- xfree(c);
+ pool->idx = 1;
+ uns aligned = ALIGN_TO(size, CPU_STRUCT_ALIGN);
+ chunk = mp_new_big_chunk(aligned);
+ chunk->next = pool->state.last[1];
+ pool->state.last[1] = chunk;
+ pool->state.free[1] = aligned - size;
+ return pool->last_big = (void *)chunk - aligned;
}
+ else
+ die("Cannot allocate %u bytes from a mempool", size);
+}
+
+void *
+mp_alloc(struct mempool *pool, uns size)
+{
+ return mp_alloc_fast(pool, size);
+}
+
+void *
+mp_alloc_noalign(struct mempool *pool, uns size)
+{
+ return mp_alloc_fast_noalign(pool, size);
+}
+
+void *
+mp_alloc_zero(struct mempool *pool, uns size)
+{
+ void *ptr = mp_alloc_fast(pool, size);
+ bzero(ptr, size);
+ return ptr;
+}
+
+void *
+mp_start_internal(struct mempool *pool, uns size)
+{
+ void *ptr = mp_alloc_internal(pool, size);
+ pool->state.free[pool->idx] += size;
+ return ptr;
+}
+
+void *
+mp_start(struct mempool *pool, uns size)
+{
+ return mp_start_fast(pool, size);
+}
+
+void *
+mp_start_noalign(struct mempool *pool, uns size)
+{
+ return mp_start_fast_noalign(pool, size);
}
void *
-mp_alloc(struct mempool *p, uns s)
+mp_grow_internal(struct mempool *pool, uns size)
{
- if (s <= p->threshold)
+ if (unlikely(size > MP_SIZE_MAX))
+ die("Cannot allocate %u bytes of memory", size);
+ uns avail = mp_avail(pool);
+ void *ptr = mp_ptr(pool);
+ if (pool->idx)
{
- byte *x = (byte *)(((uintptr_t) p->free + POOL_ALIGN - 1) & ~(uintptr_t)(POOL_ALIGN - 1));
- if (x + s > p->last)
- {
- struct memchunk *c;
-
- if (p->current)
- {
- /* Still have free chunks from previous incarnation */
- c = p->current;
- p->current = c->next;
- }
- else
- {
- c = xmalloc(sizeof(struct memchunk) + p->chunk_size);
- *p->plast = c;
- p->plast = &c->next;
- c->next = NULL;
- }
- x = c->data;
- p->last = x + p->chunk_size;
- }
- p->free = x + s;
- return x;
+ uns amortized = likely(avail <= MP_SIZE_MAX / 2) ? avail * 2 : MP_SIZE_MAX;
+ amortized = MAX(amortized, size);
+ amortized = ALIGN_TO(amortized, CPU_STRUCT_ALIGN);
+ struct mempool_chunk *chunk = pool->state.last[1], *next = chunk->next;
+ ptr = xrealloc(ptr, amortized + MP_CHUNK_TAIL);
+ chunk = ptr + amortized;
+ chunk->next = next;
+ chunk->size = amortized;
+ pool->state.last[1] = chunk;
+ pool->state.free[1] = amortized;
+ pool->last_big = ptr;
+ return ptr;
}
else
{
- struct memchunk *c = xmalloc(sizeof(struct memchunk) + s);
- c->next = p->first_large;
- p->first_large = c;
- return c->data;
+ void *p = mp_start_internal(pool, size);
+ memcpy(p, ptr, avail);
+ return p;
}
}
+uns
+mp_open(struct mempool *pool, void *ptr)
+{
+ return mp_open_fast(pool, ptr);
+}
+
+void *
+mp_realloc(struct mempool *pool, void *ptr, uns size)
+{
+ return mp_realloc_fast(pool, ptr, size);
+}
+
void *
-mp_alloc_zero(struct mempool *p, uns s)
+mp_realloc_zero(struct mempool *pool, void *ptr, uns size)
+{
+ uns old_size = mp_open_fast(pool, ptr);
+ ptr = mp_grow(pool, size);
+ if (size > old_size)
+ bzero(ptr + old_size, size - old_size);
+ mp_end(pool, ptr + size);
+ return ptr;
+}
+
+void *
+mp_spread_internal(struct mempool *pool, void *p, uns size)
+{
+ void *old = mp_ptr(pool);
+ void *new = mp_grow_internal(pool, p-old+size);
+ return p-old+new;
+}
+
+void
+mp_restore(struct mempool *pool, struct mempool_state *state)
+{
+ struct mempool_chunk *chunk, *next;
+ struct mempool_state s = *state;
+ for (chunk = pool->state.last[0]; chunk != s.last[0]; chunk = next)
+ {
+ next = chunk->next;
+ chunk->next = pool->unused;
+ pool->unused = chunk;
+ }
+ for (chunk = pool->state.last[1]; chunk != s.last[1]; chunk = next)
+ {
+ next = chunk->next;
+ mp_free_big_chunk(chunk);
+ }
+ pool->state = s;
+ pool->last_big = &pool->last_big;
+}
+
+struct mempool_state *
+mp_push(struct mempool *pool)
+{
+ struct mempool_state state = pool->state;
+ struct mempool_state *p = mp_alloc_fast(pool, sizeof(*p));
+ *p = state;
+ pool->state.next = p;
+ return p;
+}
+
+void
+mp_pop(struct mempool *pool)
+{
+ ASSERT(pool->state.next);
+ struct mempool_state state = pool->state;
+ mp_restore(pool, &state);
+}
+
+#ifdef TEST
+
+#include "lib/getopt.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+static void
+fill(byte *ptr, uns len, uns magic)
+{
+ while (len--)
+ *ptr++ = (magic++ & 255);
+}
+
+static void
+check(byte *ptr, uns len, uns magic, uns align)
{
- void *x = mp_alloc(p, s);
- bzero(x, s);
- return x;
+ ASSERT(!((uintptr_t)ptr & (align - 1)));
+ while (len--)
+ if (*ptr++ != (magic++ & 255))
+ ASSERT(0);
}
+
+int main(int argc, char **argv)
+{
+ srand(time(NULL));
+ log_init(argv[0]);
+ cf_def_file = NULL;
+ if (cf_getopt(argc, argv, CF_SHORT_OPTS, CF_NO_LONG_OPTS, NULL) >= 0 || argc != optind)
+ die("Invalid usage");
+
+ uns max = 1000, n = 0, m = 0, can_realloc = 0;
+ void *ptr[max];
+ struct mempool_state *state[max];
+ uns len[max], num[max], align[max];
+ struct mempool *mp = mp_new(128), mp_static;
+
+ for (uns i = 0; i < 5000; i++)
+ {
+ for (uns j = 0; j < n; j++)
+ check(ptr[j], len[j], j, align[j]);
+#if 0
+ DBG("free_small=%u free_big=%u idx=%u chunk_size=%u last_big=%p", mp->state.free[0], mp->state.free[1], mp->idx, mp->chunk_size, mp->last_big);
+ for (struct mempool_chunk *ch = mp->state.last[0]; ch; ch = ch->next)
+ DBG("small %p %p %p %d", (byte *)ch - ch->size, ch, ch + 1, ch->size);
+ for (struct mempool_chunk *ch = mp->state.last[1]; ch; ch = ch->next)
+ DBG("big %p %p %p %d", (byte *)ch - ch->size, ch, ch + 1, ch->size);
+#endif
+ int r = random_max(100);
+ if ((r -= 1) < 0)
+ {
+ DBG("flush");
+ mp_flush(mp);
+ n = m = 0;
+ }
+ else if ((r -= 1) < 0)
+ {
+ DBG("delete & new");
+ mp_delete(mp);
+ if (random_max(2))
+ mp = mp_new(random_max(0x1000) + 1);
+ else
+ mp = &mp_static, mp_init(mp, random_max(512) + 1);
+ n = m = 0;
+ }
+ else if (n < max && (r -= 30) < 0)
+ {
+ len[n] = random_max(0x2000);
+ DBG("alloc(%u)", len[n]);
+ align[n] = random_max(2) ? CPU_STRUCT_ALIGN : 1;
+ ptr[n] = (align[n] == 1) ? mp_alloc_fast_noalign(mp, len[n]) : mp_alloc_fast(mp, len[n]);
+ DBG(" -> (%p)", ptr[n]);
+ fill(ptr[n], len[n], n);
+ n++;
+ can_realloc = 1;
+ }
+ else if (n < max && (r -= 20) < 0)
+ {
+ len[n] = random_max(0x2000);
+ DBG("start(%u)", len[n]);
+ align[n] = random_max(2) ? CPU_STRUCT_ALIGN : 1;
+ ptr[n] = (align[n] == 1) ? mp_start_fast_noalign(mp, len[n]) : mp_start_fast(mp, len[n]);
+ DBG(" -> (%p)", ptr[n]);
+ fill(ptr[n], len[n], n);
+ n++;
+ can_realloc = 1;
+ goto grow;
+ }
+ else if (can_realloc && n && (r -= 10) < 0)
+ {
+ if (mp_open(mp, ptr[n - 1]) != len[n - 1])
+ ASSERT(0);
+grow:
+ {
+ uns k = n - 1;
+ for (uns i = random_max(4); i--; )
+ {
+ uns l = len[k];
+ len[k] = random_max(0x2000);
+ DBG("grow(%u)", len[k]);
+ ptr[k] = mp_grow(mp, len[k]);
+ DBG(" -> (%p)", ptr[k]);
+ check(ptr[k], MIN(l, len[k]), k, align[k]);
+ fill(ptr[k], len[k], k);
+ }
+ mp_end(mp, ptr[k] + len[k]);
+ }
+ }
+ else if (can_realloc && n && (r -= 20) < 0)
+ {
+ uns i = n - 1, l = len[i];
+ DBG("realloc(%p, %u)", ptr[i], len[i]);
+ ptr[i] = mp_realloc(mp, ptr[i], len[i] = random_max(0x2000));
+ DBG(" -> (%p, %u)", ptr[i], len[i]);
+ check(ptr[i], MIN(len[i], l), i, align[i]);
+ fill(ptr[i], len[i], i);
+ }
+ else if (m < max && (r -= 5) < 0)
+ {
+ DBG("push(%u)", m);
+ num[m] = n;
+ state[m++] = mp_push(mp);
+ can_realloc = 0;
+ }
+ else if (m && (r -= 2) < 0)
+ {
+ m--;
+ DBG("pop(%u)", m);
+ mp_pop(mp);
+ n = num[m];
+ can_realloc = 0;
+ }
+ else if (m && (r -= 1) < 0)
+ {
+ uns i = random_max(m);
+ DBG("restore(%u)", i);
+ mp_restore(mp, state[i]);
+ n = num[m = i];
+ can_realloc = 0;
+ }
+ else if (can_realloc && n && (r -= 5) < 0)
+ ASSERT(mp_size(mp, ptr[n - 1]) == len[n - 1]);
+ }
+
+ mp_delete(mp);
+ return 0;
+}
+
+#endif
projects / libucw.git / blobdiff