[pypy-commit] stmgc c7-refactor: A first real test for nursery collection. Fails

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: c7-refactor
Changeset: r813:07aa2f23e825
Date: 2014-02-23 14:40 +0100
http://bitbucket.org/pypy/stmgc/changeset/07aa2f23e825/

Log:	A first real test for nursery collection. Fails

diff --git a/c7/stm/gcpage.c b/c7/stm/gcpage.c
--- a/c7/stm/gcpage.c
+++ b/c7/stm/gcpage.c
@@ -24,10 +24,6 @@
     free_uniform_pages = NULL;
 }
 
-//static void check_gcpage_still_shared(void)
-//{
-//    //...;
-//}
 
 #define GCPAGE_NUM_PAGES   20
 
diff --git a/c7/stm/gcpage.h b/c7/stm/gcpage.h
--- a/c7/stm/gcpage.h
+++ b/c7/stm/gcpage.h
@@ -43,7 +43,6 @@
 
 static void setup_gcpage(void);
 static void teardown_gcpage(void);
-//static void check_gcpage_still_shared(void);
 static char *allocate_outside_nursery_large(uint64_t size);
 
 
diff --git a/c7/stm/nursery.c b/c7/stm/nursery.c
--- a/c7/stm/nursery.c
+++ b/c7/stm/nursery.c
@@ -29,6 +29,7 @@
 static union {
     struct {
         uint64_t used;    /* number of bytes from the nursery used so far */
+        uint64_t initial_value_of_used;
     };
     char reserved[64];
 } nursery_ctl __attribute__((aligned(64)));
@@ -51,6 +52,7 @@
 static void teardown_nursery(void)
 {
     list_free(old_objects_pointing_to_young);
+    nursery_ctl.initial_value_of_used = 0;
 }
 
 static inline bool _is_in_nursery(object_t *obj)
@@ -289,7 +291,7 @@
 static void reset_nursery(void)
 {
     /* reset the global amount-of-nursery-used-so-far */
-    nursery_ctl.used = 0;
+    nursery_ctl.used = nursery_ctl.initial_value_of_used;
 
     /* reset the write locks */
     memset(write_locks + ((NURSERY_START >> 4) - READMARKER_START),
@@ -332,7 +334,7 @@
         if (old_end > NURSERY_START) {
             char *creation_markers = REAL_ADDRESS(other_pseg->pub.segment_base,
                                                   NURSERY_START >> 8);
-            assert(old_end < NURSERY_START + NURSERY_SIZE);
+            assert(old_end <= NURSERY_START + NURSERY_SIZE);
             memset(creation_markers, 0, (old_end - NURSERY_START) >> 8);
         }
         else {
@@ -371,8 +373,6 @@
        information).
     */
 
-    //check_gcpage_still_shared();
-
     collect_roots_in_nursery();
 
     long i;
@@ -516,5 +516,6 @@
     assert(free_count == NURSERY_ALIGN(free_count));
     assert(nursery_ctl.used <= NURSERY_SIZE - free_count);
     nursery_ctl.used = NURSERY_SIZE - free_count;
+    nursery_ctl.initial_value_of_used = nursery_ctl.used;
 }
 #endif
diff --git a/c7/test/test_nursery.py b/c7/test/test_nursery.py
--- a/c7/test/test_nursery.py
+++ b/c7/test/test_nursery.py
@@ -58,10 +58,31 @@
         self.pop_root()
         #
         self.push_root(lp1)
-        lp2 = stm_allocate(16)
+        lp2 = stm_allocate(SOME_MEDIUM_SIZE)
         lp1b = self.pop_root()
         assert lp1b != lp1      # collection occurred
 
+    def test_several_minor_collections(self):
+        # make a long, ever-growing linked list of objects, in one transaction
+        lib._stm_set_nursery_free_count(NURSERY_SECTION_SIZE * 2)
+        self.start_transaction()
+        lp1 = stm_allocate(16)
+        self.push_root(lp1)
+        lp2 = lp1
+        N = (NURSERY_SECTION_SIZE * 5) / 16
+        for i in range(N):
+            self.push_root(lp2)
+            lp3 = stm_allocate(16)
+            lp2 = self.pop_root()
+            stm_set_ref(lp2, 0, lp3)
+            lp2 = lp3
+        lp1 = self.pop_root()
+        lp2 = lp1
+        for i in range(N):
+            assert lp2
+            lp2 = stm_get_ref(lp2, 0)
+        assert lp2 == lp3
+
     def test_many_allocs(self):
         obj_size = 1024
         num = (lib.NB_NURSERY_PAGES * 4096) / obj_size + 100 # more than what fits in the nursery