2010-07-10 Mark Probst <mark.probst@gmail.com>

	* sgen-gray.c: Store only a pointer to one end of the gray queue.

svn path=/trunk/mono/; revision=160197

diff --git a/mono/metadata/ChangeLog b/mono/metadata/ChangeLog
index 21e3b724ed894369d1563a88c03bb50896f46282..96a229fea02e348478e6c2adc0828b1e20c69372 100644 (file)
--- a/mono/metadata/ChangeLog
+++ b/mono/metadata/ChangeLog
@@ -1,3 +1,7 @@
+2010-07-10  Mark Probst  <mark.probst@gmail.com>
+
+       * sgen-gray.c: Store only a pointer to one end of the gray queue.
+
 2010-07-10 Rodrigo Kumpera  <rkumpera@novell.com>
 
        * loader.c (mono_method_signature_checked): Release the domain

diff --git a/mono/metadata/sgen-gray.c b/mono/metadata/sgen-gray.c
index 1a7f4692bd6b1b0c632475e709f1da11c83dd8b3..ef1646fc269c4fd42fea35f1cfb27b2aa0364c6d 100644 (file)
--- a/mono/metadata/sgen-gray.c
+++ b/mono/metadata/sgen-gray.c
@@ -31,13 +31,13 @@
 typedef struct _GrayQueueSection GrayQueueSection;
 struct _GrayQueueSection {
        int end;
-       GrayQueueSection *next, *prev;
+       GrayQueueSection *next;
        char *objects [GRAY_QUEUE_SECTION_SIZE];
 };
 
 struct _GrayQueue {
-       GrayQueueSection *start;
-       GrayQueueSection *end;
+       GrayQueueSection *first;
+       GrayQueueSection *free_list;
        int balance;
 };
 
@@ -48,34 +48,20 @@ gray_object_alloc_queue_section (GrayQueue *queue)
 {
        GrayQueueSection *section;
 
-       /* Use the previously allocated queue sections if possible */
-       if (!queue->end && queue->start) {
-               queue->end = queue->start;
-               queue->end->end = 0;
-               return;
-       }
-       if (queue->end && queue->end->next) {
-               queue->end = queue->end->next;
-               queue->end->end = 0;
-               return;
+       if (queue->free_list) {
+               /* Use the previously allocated queue sections if possible */
+               section = queue->free_list;
+               queue->free_list = section->next;
+       } else {
+               /* Allocate a new section */
+               section = get_internal_mem (sizeof (GrayQueueSection), INTERNAL_MEM_GRAY_QUEUE);
        }
 
-       /* Allocate a new section */
-       section = get_internal_mem (sizeof (GrayQueueSection), INTERNAL_MEM_GRAY_QUEUE);
-
        section->end = 0;
-       section->next = NULL;
-       section->prev = NULL;
 
        /* Link it with the others */
-       if (queue->end) {
-               queue->end->next = section;
-               section->prev = queue->end;
-       } else {
-               g_assert (!queue->start);
-               queue->start = section;
-       }
-       queue->end = section;
+       section->next = queue->first;
+       queue->first = section;
 }
 
 static void
@@ -87,7 +73,7 @@ gray_object_free_queue_section (GrayQueueSection *section)
 static inline gboolean
 gray_object_queue_is_empty (GrayQueue *queue)
 {
-       return queue->end == NULL;
+       return queue->first == NULL;
 }
 
 /*
@@ -100,10 +86,10 @@ static inline void
 gray_object_enqueue (GrayQueue *queue, char *obj)
 {
        DEBUG (9, g_assert (obj));
-       if (G_UNLIKELY (!queue->end || queue->end->end == GRAY_QUEUE_SECTION_SIZE))
+       if (G_UNLIKELY (!queue->first || queue->first->end == GRAY_QUEUE_SECTION_SIZE))
                gray_object_alloc_queue_section (queue);
-       DEBUG (9, g_assert (queue->end && queue->end->end < GRAY_QUEUE_SECTION_SIZE));
-       queue->end->objects [queue->end->end++] = obj;
+       DEBUG (9, g_assert (queue->first && queue->first->end < GRAY_QUEUE_SECTION_SIZE));
+       queue->first->objects [queue->first->end++] = obj;
 
        DEBUG (9, ++queue->balance);
 }
@@ -116,12 +102,16 @@ gray_object_dequeue (GrayQueue *queue)
        if (gray_object_queue_is_empty (queue))
                return NULL;
 
-       DEBUG (9, g_assert (queue->end->end));
+       DEBUG (9, g_assert (queue->first->end));
 
-       obj = queue->end->objects [--queue->end->end];
+       obj = queue->first->objects [--queue->first->end];
 
-       if (G_UNLIKELY (queue->end->end == 0))
-               queue->end = queue->end->prev;
+       if (G_UNLIKELY (queue->first->end == 0)) {
+               GrayQueueSection *section = queue->first;
+               queue->first = section->next;
+               section->next = queue->free_list;
+               queue->free_list = section;
+       }
 
        DEBUG (9, --queue->balance);
 
@@ -133,18 +123,17 @@ gray_object_dequeue (GrayQueue *queue)
 #define GRAY_OBJECT_DEQUEUE(queue,o) ((o) = gray_object_dequeue ((queue)))
 #else
 #define GRAY_OBJECT_ENQUEUE(queue,o) do {                              \
-               if (G_UNLIKELY (!(queue)->end || (queue)->end->end == GRAY_QUEUE_SECTION_SIZE)) \
+               if (G_UNLIKELY (!(queue)->first || (queue)->first->end == GRAY_QUEUE_SECTION_SIZE)) \
                        gray_object_alloc_queue_section ((queue));      \
-               (queue)->end->objects [(queue)->end->end++] = (o);      \
+               (queue)->first->objects [(queue)->first->end++] = (o);  \
        } while (0)
 #define GRAY_OBJECT_DEQUEUE(queue,o) do {                              \
-               if (!(queue)->end) {                                    \
+               if (!(queue)->first)                                    \
                        (o) = NULL;                                     \
-               } else {                                                \
-                       (o) = (queue)->end->objects [--(queue)->end->end]; \
-                       if (G_UNLIKELY ((queue)->end->end == 0))        \
-                               (queue)->end = (queue)->end->prev;      \
-               }                                                       \
+               else if (G_UNLIKELY ((queue)->first->end == 1))         \
+                       (o) = gray_object_dequeue ((queue));            \
+               else                                                    \
+                       (o) = (queue)->first->objects [--(queue)->first->end]; \
        } while (0)
 #endif
 
@@ -160,14 +149,13 @@ gray_object_queue_init (GrayQueue *queue)
 
        /* Free the extra sections allocated during the last collection */
        i = 0;
-       for (section = queue->start; section && i < GRAY_QUEUE_LENGTH_LIMIT; section = section->next)
+       for (section = queue->free_list; section && i < GRAY_QUEUE_LENGTH_LIMIT - 1; section = section->next)
                i ++;
-       if (section) {
-               if (section->prev)
-                       section->prev->next = NULL;
-               for (; section; section = next) {
-                       next = section->next;
-                       gray_object_free_queue_section (section);
-               }
+       if (!section)
+               return;
+       while (section->next) {
+               next = section->next;
+               section->next = next->next;
+               gray_object_free_queue_section (next);
        }
 }