Commit 1ef120f5 authored by Paul Bakker's avatar Paul Bakker
Browse files

Updated buffer-allocator with free-block-list to speed up searches

parent 41350a9a
......@@ -50,6 +50,8 @@ struct _memory_header
size_t alloc;
memory_header *prev;
memory_header *next;
memory_header *prev_free;
memory_header *next_free;
#if defined(POLARSSL_MEMORY_BACKTRACE)
char **trace;
size_t trace_count;
......@@ -62,7 +64,7 @@ typedef struct
unsigned char *buf;
size_t len;
memory_header *first;
size_t largest_free;
memory_header *first_free;
size_t current_alloc_size;
int verify;
#if defined(POLARSSL_MEMORY_DEBUG)
......@@ -87,11 +89,14 @@ static void debug_header( memory_header *hdr )
fprintf( stderr, "HDR: PTR(%10u), PREV(%10u), NEXT(%10u), ALLOC(%u), SIZE(%10u)\n",
(size_t) hdr, (size_t) hdr->prev, (size_t) hdr->next,
hdr->alloc, hdr->size );
fprintf( stderr, " FPREV(%10u), FNEXT(%10u)\n",
(size_t) hdr->prev_free, (size_t) hdr->next_free );
#if defined(POLARSSL_MEMORY_BACKTRACE)
fprintf( stderr, "TRACE: \n" );
for( i = 0; i < hdr->trace_count; i++ )
fprintf( stderr, "%s\n", hdr->trace[i] );
fprintf( stderr, "\n" );
#endif
}
......@@ -99,12 +104,21 @@ static void debug_chain()
{
memory_header *cur = heap.first;
fprintf( stderr, "\nBlock list\n" );
while( cur != NULL )
{
debug_header( cur );
fprintf( stderr, "\n" );
cur = cur->next;
}
fprintf( stderr, "Free list\n" );
cur = heap.first_free;
while( cur != NULL )
{
debug_header( cur );
cur = cur->next_free;
}
}
#endif /* POLARSSL_MEMORY_DEBUG */
......@@ -134,6 +148,22 @@ static int verify_header( memory_header *hdr )
return( 1 );
}
if( hdr->prev != NULL && hdr->prev == hdr->next )
{
#if defined(POLARSSL_MEMORY_DEBUG)
fprintf( stderr, "FATAL: prev == next\n" );
#endif
return( 1 );
}
if( hdr->prev_free != NULL && hdr->prev_free == hdr->next_free )
{
#if defined(POLARSSL_MEMORY_DEBUG)
fprintf( stderr, "FATAL: prev_free == next_free\n" );
#endif
return( 1 );
}
return( 0 );
}
......@@ -184,7 +214,7 @@ static int verify_chain()
static void *buffer_alloc_malloc( size_t len )
{
memory_header *new, *cur = heap.first;
memory_header *new, *cur = heap.first_free;
unsigned char *p;
#if defined(POLARSSL_MEMORY_BACKTRACE)
void *trace_buffer[MAX_BT];
......@@ -204,15 +234,23 @@ static void *buffer_alloc_malloc( size_t len )
//
while( cur != NULL )
{
if( cur->alloc == 0 && cur->size >= len )
if( cur->size >= len )
break;
cur = cur->next;
cur = cur->next_free;
}
if( cur == NULL )
return( NULL );
if( cur->alloc != 0 )
{
#if defined(POLARSSL_MEMORY_DEBUG)
fprintf( stderr, "FATAL: block in free_list but allocated data\n" );
#endif
exit( 1 );
}
#if defined(POLARSSL_MEMORY_DEBUG)
heap.malloc_count++;
#endif
......@@ -223,6 +261,19 @@ static void *buffer_alloc_malloc( size_t len )
{
cur->alloc = 1;
// Remove from free_list
//
if( cur->prev_free != NULL )
cur->prev_free->next_free = cur->next_free;
else
heap.first_free = cur->next_free;
if( cur->next_free != NULL )
cur->next_free->prev_free = cur->prev_free;
cur->prev_free = NULL;
cur->next_free = NULL;
#if defined(POLARSSL_MEMORY_DEBUG)
heap.total_used += cur->size;
if( heap.total_used > heap.maximum_used)
......@@ -257,9 +308,23 @@ static void *buffer_alloc_malloc( size_t len )
if( new->next != NULL )
new->next->prev = new;
// Replace cur with new in free_list
//
new->prev_free = cur->prev_free;
new->next_free = cur->next_free;
if( new->prev_free != NULL )
new->prev_free->next_free = new;
else
heap.first_free = new;
if( new->next_free != NULL )
new->next_free->prev_free = new;
cur->alloc = 1;
cur->size = len;
cur->next = new;
cur->prev_free = NULL;
cur->next_free = NULL;
#if defined(POLARSSL_MEMORY_DEBUG)
heap.header_count++;
......@@ -281,7 +346,7 @@ static void *buffer_alloc_malloc( size_t len )
static void buffer_alloc_free( void *ptr )
{
memory_header *hdr, *old;
memory_header *hdr, *old = NULL;
unsigned char *p = (unsigned char *) ptr;
......@@ -349,6 +414,28 @@ static void buffer_alloc_free( void *ptr )
old = hdr->next;
hdr->next = hdr->next->next;
if( hdr->prev_free != NULL || hdr->next_free != NULL )
{
if( hdr->prev_free != NULL )
hdr->prev_free->next_free = hdr->next_free;
else
heap.first_free = hdr->next_free;
if( hdr->next_free != NULL )
hdr->next_free->prev_free = hdr->prev_free;
}
hdr->prev_free = old->prev_free;
hdr->next_free = old->next_free;
if( hdr->prev_free != NULL )
hdr->prev_free->next_free = hdr;
else
heap.first_free = hdr;
if( hdr->next_free != NULL )
hdr->next_free->prev_free = hdr;
if( hdr->next != NULL )
hdr->next->prev = hdr;
......@@ -358,6 +445,16 @@ static void buffer_alloc_free( void *ptr )
memset( old, 0, sizeof(memory_header) );
}
// Prepend to free_list if we have not merged
// (Does not have to stay in same order as prev / next list)
//
if( old == NULL )
{
hdr->next_free = heap.first_free;
heap.first_free->prev_free = hdr;
heap.first_free = hdr;
}
#if defined(POLARSSL_MEMORY_BACKTRACE)
hdr->trace = NULL;
hdr->trace_count = 0;
......@@ -405,9 +502,7 @@ int memory_buffer_alloc_init( unsigned char *buf, size_t len )
heap.first->size = len - sizeof(memory_header);
heap.first->magic1 = MAGIC1;
heap.first->magic2 = MAGIC2;
heap.largest_free = heap.first->size;
heap.first_free = heap.first;
return( 0 );
}
......
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