merge from dev; free huge objects directly and keep them abandoned

src/alloc.c

@@ -115,6 +115,21 @@ static mi_decl_noinline void _mi_free_block_mt(mi_page_t* page, mi_block_t* bloc
   mi_thread_free_t tfreex;
   bool use_delayed;
 
+  mi_segment_t* segment = _mi_page_segment(page);
+  if (segment->kind==MI_SEGMENT_HUGE) {
+    // huge page segments are always abandoned and can be freed immediately
+    mi_assert_internal(segment->thread_id==0);
+    mi_assert_internal(segment->abandoned_next==NULL);
+    // claim it and immediately free it
+    mi_block_set_next(page, block, page->free);
+    page->free = block;
+    page->used--;
+    mi_heap_t* heap = mi_get_default_heap();
+    segment->thread_id = heap->thread_id;
+    _mi_segment_page_free(page,true,&heap->tld->segments);
+    return;
+  }
+
   do {
     tfree = page->thread_free;
     use_delayed = (mi_tf_delayed(tfree) == MI_USE_DELAYED_FREE ||

src/page-queue.c

@@ -268,6 +268,7 @@ static void mi_page_queue_remove(mi_page_queue_t* queue, mi_page_t* page) {
 static void mi_page_queue_push(mi_heap_t* heap, mi_page_queue_t* queue, mi_page_t* page) {
   mi_assert_internal(page->heap == NULL);
   mi_assert_internal(!mi_page_queue_contains(queue, page));
+  mi_assert_internal(_mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
   mi_assert_internal(page->block_size == queue->block_size ||
                       (page->block_size > MI_MEDIUM_OBJ_SIZE_MAX && mi_page_queue_is_huge(queue)) ||
                         (mi_page_is_in_full(page) && mi_page_queue_is_full(queue)));

src/page.c

@@ -98,10 +98,12 @@ bool _mi_page_is_valid(mi_page_t* page) {
   if (page->heap!=NULL) {
     mi_segment_t* segment = _mi_page_segment(page);
     mi_assert_internal(!_mi_process_is_initialized || segment->thread_id==0 || segment->thread_id == page->heap->thread_id);
-    mi_page_queue_t* pq = mi_page_queue_of(page);
-    mi_assert_internal(mi_page_queue_contains(pq, page));
-    mi_assert_internal(pq->block_size==page->block_size || page->block_size > MI_MEDIUM_OBJ_SIZE_MAX || mi_page_is_in_full(page));
-    mi_assert_internal(mi_heap_contains_queue(page->heap,pq));
+    if (segment->kind != MI_SEGMENT_HUGE) {
+      mi_page_queue_t* pq = mi_page_queue_of(page);
+      mi_assert_internal(mi_page_queue_contains(pq, page));
+      mi_assert_internal(pq->block_size==page->block_size || page->block_size > MI_MEDIUM_OBJ_SIZE_MAX || mi_page_is_in_full(page));
+      mi_assert_internal(mi_heap_contains_queue(page->heap,pq));
+    }
   }
   return true;
 }
@@ -207,6 +209,7 @@ void _mi_page_free_collect(mi_page_t* page, bool force) {
 void _mi_page_reclaim(mi_heap_t* heap, mi_page_t* page) {
   mi_assert_expensive(mi_page_is_valid_init(page));
   mi_assert_internal(page->heap == NULL);
+  mi_assert_internal(_mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
   _mi_page_free_collect(page,false);
   mi_page_queue_t* pq = mi_page_queue(heap, page->block_size);
   mi_page_queue_push(heap, pq, page);
@@ -215,12 +218,13 @@ void _mi_page_reclaim(mi_heap_t* heap, mi_page_t* page) {
 
 // allocate a fresh page from a segment
 static mi_page_t* mi_page_fresh_alloc(mi_heap_t* heap, mi_page_queue_t* pq, size_t block_size) {
-  mi_assert_internal(mi_heap_contains_queue(heap, pq));
+  mi_assert_internal(pq==NULL||mi_heap_contains_queue(heap, pq));
   mi_page_t* page = _mi_segment_page_alloc(block_size, &heap->tld->segments, &heap->tld->os);
   if (page == NULL) return NULL;
+  mi_assert_internal(pq==NULL || _mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
   mi_page_init(heap, page, block_size, &heap->tld->stats);
   _mi_stat_increase( &heap->tld->stats.pages, 1);
-  mi_page_queue_push(heap, pq, page);
+  if (pq!=NULL) mi_page_queue_push(heap, pq, page); // huge pages use pq==NULL
   mi_assert_expensive(_mi_page_is_valid(page));
   return page;
 }
@@ -701,16 +705,26 @@ void mi_register_deferred_free(mi_deferred_free_fun* fn) mi_attr_noexcept {
   General allocation
 ----------------------------------------------------------- */
 
-// Large and huge pages are allocated directly without being in a queue
+// Large and huge pages are allocated directly 
 static mi_page_t* mi_large_page_alloc(mi_heap_t* heap, size_t size) {
   size_t block_size = _mi_wsize_from_size(size) * sizeof(uintptr_t);
   mi_assert_internal(_mi_bin(block_size) == MI_BIN_HUGE); 
-  mi_page_queue_t* pq = mi_page_queue(heap,block_size);
-  mi_assert_internal(mi_page_queue_is_huge(pq));
+  bool is_huge = (block_size > MI_LARGE_OBJ_SIZE_MAX);
+  mi_page_queue_t* pq = (is_huge ? NULL : mi_page_queue(heap,block_size));
   mi_page_t* page = mi_page_fresh_alloc(heap,pq,block_size);
   if (page != NULL) {
     mi_assert_internal(mi_page_immediate_available(page));
     mi_assert_internal(page->block_size == block_size);
+    if (pq == NULL) {
+      // huge pages are directly abandoned
+      mi_assert_internal(_mi_page_segment(page)->kind == MI_SEGMENT_HUGE);
+      mi_assert_internal(_mi_page_segment(page)->used==1);
+      mi_assert_internal(_mi_page_segment(page)->thread_id==0); // abandoned, not in the huge queue
+      page->heap = NULL;
+    }
+    else {
+      mi_assert_internal(_mi_page_segment(page)->kind != MI_SEGMENT_HUGE);
+    }
     if (page->block_size <= MI_LARGE_OBJ_SIZE_MAX) {
       _mi_stat_increase(&heap->tld->stats.large, block_size);
       _mi_stat_counter_increase(&heap->tld->stats.large_count, 1);

src/segment.c

@@ -915,6 +915,7 @@ static mi_page_t* mi_segment_huge_page_alloc(size_t size, mi_segments_tld_t* tld
   if (segment == NULL || page==NULL) return NULL;
   mi_assert_internal(segment->used==1);
   mi_assert_internal(page->block_size >= size);
+  segment->thread_id = 0; // huge segments are immediately abandoned
   return page;
 }