We now pass the POOL_QALIGN flag to pool_create(). Also optimized
[rsync/rsync.git] / lib / pool_alloc.c
index 5cf9fbc..0fb3122 100644 (file)
@@ -6,21 +6,18 @@ struct alloc_pool
 {
        size_t                  size;           /* extent size          */
        size_t                  quantum;        /* allocation quantum   */
-       struct pool_extent      *live;          /* current extent for
-                                                * allocations          */
-       struct pool_extent      *free;          /* unfreed extent list  */
-       void                    (*bomb)();
-                                               /* function to call if
+       struct pool_extent      *extents;       /* top extent is "live" */
+       void                    (*bomb)();      /* function to call if
                                                 * malloc fails         */
        int                     flags;
 
        /* statistical data */
        unsigned long           e_created;      /* extents created      */
        unsigned long           e_freed;        /* extents detroyed     */
-       uint64                  n_allocated;    /* calls to alloc       */
-       uint64                  n_freed;        /* calls to free        */
-       uint64                  b_allocated;    /* cum. bytes allocated */
-       uint64                  b_freed;        /* cum. bytes freed     */
+       int64                   n_allocated;    /* calls to alloc       */
+       int64                   n_freed;        /* calls to free        */
+       int64                   b_allocated;    /* cum. bytes allocated */
+       int64                   b_freed;        /* cum. bytes freed     */
 };
 
 struct pool_extent
@@ -33,8 +30,8 @@ struct pool_extent
 };
 
 struct align_test {
-    void *foo;
-    uint64 bar;
+       void *foo;
+       int64 bar;
 };
 
 #define MINALIGN       offsetof(struct align_test, bar)
@@ -44,20 +41,18 @@ struct align_test {
 #define PTR_ADD(b,o)   ( (void*) ((char*)(b) + (o)) )
 
 alloc_pool_t
-pool_create(size_t size, size_t quantum,
-    void (*bomb)(char *), int flags)
+pool_create(size_t size, size_t quantum, void (*bomb)(const char *), int flags)
 {
        struct alloc_pool       *pool;
 
-       if (!(pool = (struct alloc_pool*) malloc(sizeof (struct alloc_pool))))
+       if (!(pool = new(struct alloc_pool)))
                return pool;
        memset(pool, 0, sizeof (struct alloc_pool));
 
        pool->size = size       /* round extent size to min alignment reqs */
            ? (size + MINALIGN - 1) & ~(MINALIGN - 1)
            : POOL_DEF_EXTENT;
-       if (pool->flags & POOL_INTERN)
-       {
+       if (flags & POOL_INTERN) {
                pool->size -= sizeof (struct pool_extent);
                flags |= POOL_APPEND;
        }
@@ -77,15 +72,7 @@ pool_destroy(alloc_pool_t p)
        if (!pool)
                return;
 
-       if (pool->live)
-       {
-               cur = pool->live;
-               free(cur->start);
-               if (!(pool->flags & POOL_APPEND))
-                       free(cur);
-       }
-       for (cur = pool->free; cur; cur = next)
-       {
+       for (cur = pool->extents; cur; cur = next) {
                next = cur->next;
                free(cur->start);
                if (!(pool->flags & POOL_APPEND))
@@ -95,7 +82,7 @@ pool_destroy(alloc_pool_t p)
 }
 
 void *
-pool_alloc(alloc_pool_t p, size_t len, char *bomb)
+pool_alloc(alloc_pool_t p, size_t len, const char *bomb_msg)
 {
        struct alloc_pool *pool = (struct alloc_pool *) p;
        if (!pool)
@@ -107,21 +94,15 @@ pool_alloc(alloc_pool_t p, size_t len, char *bomb)
                len += pool->quantum - len % pool->quantum;
 
        if (len > pool->size)
-               goto bomb;
+               goto bomb_out;
 
-       if (!pool->live || len > pool->live->free)
-       {
+       if (!pool->extents || len > pool->extents->free) {
                void    *start;
                size_t  free;
                size_t  bound;
-               size_t  sqew;
+               size_t  skew;
                size_t  asize;
-
-               if (pool->live)
-               {
-                       pool->live->next = pool->free;
-                       pool->free = pool->live;
-               }
+               struct pool_extent *ext;
 
                free = pool->size;
                bound = 0;
@@ -130,30 +111,26 @@ pool_alloc(alloc_pool_t p, size_t len, char *bomb)
                if (pool->flags & POOL_APPEND)
                        asize += sizeof (struct pool_extent);
 
-               if (!(start = (void *) malloc(asize)))
-                       goto bomb;
+               if (!(start = new_array(char, asize)))
+                       goto bomb_out;
 
                if (pool->flags & POOL_CLEAR)
-                       memset(start, 0, pool->size);
+                       memset(start, 0, free);
 
                if (pool->flags & POOL_APPEND)
-               {
-                       pool->live = PTR_ADD(start, free);
-               }
-               else if (!(pool->live = (struct pool_extent *) malloc(sizeof (struct pool_extent))))
-               {
-                       goto bomb;
-               }
+                       ext = PTR_ADD(start, free);
+               else if (!(ext = new(struct pool_extent)))
+                       goto bomb_out;
                if (pool->flags & POOL_QALIGN && pool->quantum > 1
-                   && (sqew = (size_t)PTR_ADD(start, free) % pool->quantum))
-               {
-                       bound  += sqew;
-                       free -= sqew;
+                   && (skew = (size_t)PTR_ADD(start, free) % pool->quantum)) {
+                       bound  += skew;
+                       free -= skew;
                }
-               pool->live->start = start;
-               pool->live->free = free;
-               pool->live->bound = bound;
-               pool->live->next = NULL;
+               ext->start = start;
+               ext->free = free;
+               ext->bound = bound;
+               ext->next = pool->extents;
+               pool->extents = ext;
 
                pool->e_created++;
        }
@@ -161,22 +138,24 @@ pool_alloc(alloc_pool_t p, size_t len, char *bomb)
        pool->n_allocated++;
        pool->b_allocated += len;
 
-       pool->live->free -= len;
+       pool->extents->free -= len;
 
-       return PTR_ADD(pool->live->start, pool->live->free);
+       return PTR_ADD(pool->extents->start, pool->extents->free);
 
-bomb:
+  bomb_out:
        if (pool->bomb)
-               (*pool->bomb)(bomb);
+               (*pool->bomb)(bomb_msg);
        return NULL;
 }
 
+/* This function allows you to declare memory in the pool that you are done
+ * using.  If you free all the memory in a pool's extent, that extent will
+ * be freed. */
 void
 pool_free(alloc_pool_t p, size_t len, void *addr)
 {
-       struct alloc_pool *pool = (struct alloc_pool *) p;
-       struct pool_extent      *cur;
-       struct pool_extent      *prev;
+       struct alloc_pool *pool = (struct alloc_pool *)p;
+       struct pool_extent *cur, *prev;
 
        if (!pool)
                return;
@@ -186,46 +165,71 @@ pool_free(alloc_pool_t p, size_t len, void *addr)
        else if (pool->quantum > 1 && len % pool->quantum)
                len += pool->quantum - len % pool->quantum;
 
-       if (!addr && pool->live)
-       {
-               pool->live->next = pool->free;
-               pool->free = pool->live;
-               pool->live = NULL;
-               return;
-       }
        pool->n_freed++;
        pool->b_freed += len;
 
-       cur = pool->live;
-       if (cur
-           && addr >= cur->start
-           && addr < PTR_ADD(cur->start, pool->size))
-       {
-               if (addr == PTR_ADD(cur->start, cur->free))
-               {
-                       if (pool->flags & POOL_CLEAR)
-                               memset(addr, 0, len);
-                       pool->b_freed += len;
-               } else {
-                       cur->bound += len;
-               }
-               if (cur->free + cur->bound >= pool->size)
-               {
-                       size_t sqew;
+       for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) {
+               if (addr >= cur->start
+                   && addr < PTR_ADD(cur->start, pool->size))
+                       break;
+       }
+       if (!cur)
+               return;
+
+       if (!prev) {
+               /* The "live" extent is kept ready for more allocations. */
+               if (cur->free + cur->bound + len >= pool->size) {
+                       size_t skew;
 
+                       if (pool->flags & POOL_CLEAR) {
+                               memset(PTR_ADD(cur->start, cur->free), 0,
+                                      pool->size - cur->free);
+                       }
                        cur->free = pool->size;
                        cur->bound = 0;
                        if (pool->flags & POOL_QALIGN && pool->quantum > 1
-                           && (sqew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum))
-                       {
-                               cur->bound += sqew;
-                               cur->free -= sqew;
+                           && (skew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum)) {
+                               cur->bound += skew;
+                               cur->free -= skew;
                        }
+               } else if (addr == PTR_ADD(cur->start, cur->free)) {
+                       if (pool->flags & POOL_CLEAR)
+                               memset(addr, 0, len);
+                       cur->free += len;
+               } else
+                       cur->bound += len;
+       } else {
+               cur->bound += len;
+
+               if (cur->free + cur->bound >= pool->size) {
+                       prev->next = cur->next;
+                       free(cur->start);
+                       if (!(pool->flags & POOL_APPEND))
+                               free(cur);
+                       pool->e_freed++;
+               } else if (prev != pool->extents) {
+                       /* Move the extent to be the first non-live extent. */
+                       prev->next = cur->next;
+                       cur->next = pool->extents->next;
+                       pool->extents->next = cur;
                }
-               return;
        }
-       for (prev = NULL, cur = pool->free; cur; prev = cur, cur = cur->next)
-       {
+}
+
+/* This allows you to declare that the given address marks the edge of some
+ * pool memory that is no longer needed.  Any extents that hold only data
+ * older than the boundary address are freed.  NOTE: You MUST NOT USE BOTH
+ * pool_free() and pool_free_old() on the same pool!! */
+void
+pool_free_old(alloc_pool_t p, void *addr)
+{
+       struct alloc_pool *pool = (struct alloc_pool *)p;
+       struct pool_extent *cur, *prev, *next;
+
+       if (!pool || !addr)
+               return;
+
+       for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) {
                if (addr >= cur->start
                    && addr < PTR_ADD(cur->start, pool->size))
                        break;
@@ -233,32 +237,69 @@ pool_free(alloc_pool_t p, size_t len, void *addr)
        if (!cur)
                return;
 
-       if (prev)
-       {
-               prev->next = cur->next;
-               cur->next = pool->free;
-               pool->free = cur;
-       }
-       cur->bound += len;
+       if (addr == PTR_ADD(cur->start, cur->free)) {
+               if (prev) {
+                       prev->next = NULL;
+                       next = cur;
+               } else {
+                       size_t skew;
 
-       if (cur->free + cur->bound >= pool->size)
-       {
-               pool->free = cur->next;
+                       /* The most recent live extent can just be reset. */
+                       if (pool->flags & POOL_CLEAR)
+                               memset(addr, 0, pool->size - cur->free);
+                       cur->free = pool->size;
+                       cur->bound = 0;
+                       if (pool->flags & POOL_QALIGN && pool->quantum > 1
+                           && (skew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum)) {
+                               cur->bound += skew;
+                               cur->free -= skew;
+                       }
+                       next = cur->next;
+                       cur->next = NULL;
+               }
+       } else {
+               next = cur->next;
+               cur->next = NULL;
+       }
 
+       while ((cur = next) != NULL) {
+               next = cur->next;
                free(cur->start);
                if (!(pool->flags & POOL_APPEND))
                        free(cur);
                pool->e_freed++;
        }
-       return;
+}
+
+/* If the current extent doesn't have "len" free space in it, mark it as full
+ * so that the next alloc will start a new extent.  If len is (size_t)-1, this
+ * bump will always occur.  The function returns a boundary address that can
+ * be used with pool_free_old(), or a NULL if no memory is allocated. */
+void *
+pool_boundary(alloc_pool_t p, size_t len)
+{
+       struct alloc_pool *pool = (struct alloc_pool *)p;
+       struct pool_extent *cur;
+
+       if (!pool || !pool->extents)
+               return NULL;
+
+       cur = pool->extents;
+
+       if (cur->free < len) {
+               cur->bound += cur->free;
+               cur->free = 0;
+       }
+
+       return PTR_ADD(cur->start, cur->free);
 }
 
 #define FDPRINT(label, value) \
-       snprintf(buf, BUFSIZ, label, value), \
-       write(fd, buf, strlen(buf));
+       snprintf(buf, sizeof buf, label, value), \
+       write(fd, buf, strlen(buf))
 
 #define FDEXTSTAT(ext) \
-       snprintf(buf, BUFSIZ, "  %12ld  %5ld\n", \
+       snprintf(buf, sizeof buf, "  %12ld  %5ld\n", \
                (long) ext->free, \
                (long) ext->bound), \
        write(fd, buf, strlen(buf))
@@ -279,26 +320,17 @@ pool_stats(alloc_pool_t p, int fd, int summarize)
        FDPRINT("  Extents freed:     %12ld\n",         pool->e_freed);
        FDPRINT("  Alloc count:       %12.0f\n", (double) pool->n_allocated);
        FDPRINT("  Free Count:        %12.0f\n", (double) pool->n_freed);
-       FDPRINT("  Alloc bytes:       %12.0f\n", (double) pool->b_allocated);
-       FDPRINT("  Free bytes:        %12.0f\n", (double) pool->b_freed);
+       FDPRINT("  Bytes allocated:   %12.0f\n", (double) pool->b_allocated);
+       FDPRINT("  Bytes freed:       %12.0f\n", (double) pool->b_freed);
 
        if (summarize)
                return;
 
-       if (!pool->live && !pool->free)
+       if (!pool->extents)
                return;
 
        write(fd, "\n", 1);
 
-       if (pool->live)
-       {
-               FDEXTSTAT(pool->live);
-       }
-       strcpy(buf, "   FREE    BOUND\n");
-       write(fd, buf, strlen(buf));
-
-       for (cur = pool->free; cur; cur = cur->next)
-       {
+       for (cur = pool->extents; cur; cur = cur->next)
                FDEXTSTAT(cur);
-       }
 }