[pypy-commit] stmgc c7-refactor: Replace stm_allocate_prebuilt() with stm_copy_prebuilt_objects()

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: c7-refactor
Changeset: r726:a73a0beed91e
Date: 2014-02-11 15:49 +0100
http://bitbucket.org/pypy/stmgc/changeset/a73a0beed91e/

Log:	Replace stm_allocate_prebuilt() with stm_copy_prebuilt_objects()
	which is probably a better fit for PyPy.

diff --git a/c7/stm/gcpage.c b/c7/stm/gcpage.c
--- a/c7/stm/gcpage.c
+++ b/c7/stm/gcpage.c
@@ -9,11 +9,6 @@
                            (NB_PAGES - END_NURSERY_PAGE) * 4096UL);
 }
 
-object_t *stm_allocate_prebuilt(ssize_t size_rounded_up)
-{
-    abort();
-}
-
 object_t *_stm_allocate_old(ssize_t size_rounded_up)
 {
     char *addr = large_malloc(size_rounded_up);
diff --git a/c7/stm/prebuilt.c b/c7/stm/prebuilt.c
new file mode 100644
--- /dev/null
+++ b/c7/stm/prebuilt.c
@@ -0,0 +1,41 @@
+#ifndef _STM_CORE_H_
+# error "must be compiled via stmgc.c"
+#endif
+
+
+void stm_copy_prebuilt_objects(object_t *target, char *source, ssize_t size)
+{
+    /* Initialize a region of 'size' bytes at the 'target' address,
+       containing prebuilt objects copied from 'source'.  The caller
+       must ensure that the 'target' address is valid.  It might be
+       called several times but care must be taken not to overlap the
+       ranges.  The exact rules are a bit complicated:
+
+       - the range [target, target + size] must be inside the
+         range [131072, FIRST_READMARKER_PAGE*4096]
+
+       - the range [target / 16, (target + size) / 16] will be
+         used by read markers, so it must be fully before the
+         range [target, target + size].
+
+       The objects themselves can contain more pointers to other
+       prebuilt objects.  Their stm_flags field must be initialized
+       with STM_FLAGS_PREBUILT.
+    */
+
+    uintptr_t utarget = (uintptr_t)target;
+    if (utarget / 16 < 8192 ||
+            utarget + size > FIRST_READMARKER_PAGE * 4096UL ||
+            (utarget + size + 15) / 16 > utarget) {
+        fprintf(stderr,
+                "stm_copy_prebuilt_objects: invalid range (%ld, %ld)",
+                (long)utarget, (long)size);
+        abort();
+    }
+    uintptr_t start_page = utarget / 4096;
+    uintptr_t end_page = (utarget + size + 4095) / 4096;
+    pages_initialize_shared(start_page, end_page - start_page);
+
+    char *segment_base = get_segment_base(0);
+    memcpy(REAL_ADDRESS(segment_base, utarget), source, size);
+}
diff --git a/c7/stmgc.c b/c7/stmgc.c
--- a/c7/stmgc.c
+++ b/c7/stmgc.c
@@ -7,6 +7,7 @@
 
 #include "stm/misc.c"
 #include "stm/pages.c"
+#include "stm/prebuilt.c"
 #include "stm/gcpage.c"
 #include "stm/largemalloc.c"
 #include "stm/nursery.c"
diff --git a/c7/stmgc.h b/c7/stmgc.h
--- a/c7/stmgc.h
+++ b/c7/stmgc.h
@@ -78,6 +78,7 @@
 #endif
 
 #define _STM_GCFLAG_WRITE_BARRIER  0x01
+#define STM_FLAGS_PREBUILT         _STM_GCFLAG_WRITE_BARRIER
 
 
 /* ==================== HELPERS ==================== */
@@ -140,12 +141,11 @@
     return (object_t *)p;
 }
 
-object_t *stm_allocate_prebuilt(ssize_t size_rounded_up);
-
 void stm_setup(void);
 void stm_teardown(void);
 void stm_register_thread_local(stm_thread_local_t *tl);
 void stm_unregister_thread_local(stm_thread_local_t *tl);
+void stm_copy_prebuilt_objects(object_t *target, char *source, ssize_t size);
 
 void stm_start_transaction(stm_thread_local_t *tl, stm_jmpbuf_t *jmpbuf);
 void stm_start_inevitable_transaction(stm_thread_local_t *tl);
diff --git a/c7/test/support.py b/c7/test/support.py
--- a/c7/test/support.py
+++ b/c7/test/support.py
@@ -41,11 +41,13 @@
 void stm_read(object_t *obj);
 /*void stm_write(object_t *obj); use _checked_stm_write() instead */
 object_t *stm_allocate(ssize_t size_rounded_up);
-object_t *stm_allocate_prebuilt(ssize_t size_rounded_up);
 object_t *_stm_allocate_old(ssize_t size_rounded_up);
 
 void stm_setup(void);
 void stm_teardown(void);
+void stm_register_thread_local(stm_thread_local_t *tl);
+void stm_unregister_thread_local(stm_thread_local_t *tl);
+void stm_copy_prebuilt_objects(object_t *target, char *source, ssize_t size);
 
 bool _checked_stm_write(object_t *obj);
 bool _stm_was_read(object_t *obj);
@@ -56,9 +58,6 @@
 bool _stm_in_transaction(stm_thread_local_t *tl);
 void _stm_test_switch(stm_thread_local_t *tl);
 
-void stm_register_thread_local(stm_thread_local_t *tl);
-void stm_unregister_thread_local(stm_thread_local_t *tl);
-
 void stm_start_transaction(stm_thread_local_t *tl, stm_jmpbuf_t *jmpbuf);
 void stm_commit_transaction(void);
 bool _check_abort_transaction(void);