[pypy-svn] r77038 - in pypy/branch/gen2-gc/pypy/rpython/memory/gc: . test

[arigo at codespeak.net]

Author: arigo
Date: Mon Sep 13 14:18:55 2010
New Revision: 77038

Added:
   pypy/branch/gen2-gc/pypy/rpython/memory/gc/gen2.py   (contents, props changed)
   pypy/branch/gen2-gc/pypy/rpython/memory/gc/test/test_gen2.py   (contents, props changed)
Log:
Start.


Added: pypy/branch/gen2-gc/pypy/rpython/memory/gc/gen2.py
==============================================================================
--- (empty file)
+++ pypy/branch/gen2-gc/pypy/rpython/memory/gc/gen2.py	Mon Sep 13 14:18:55 2010
@@ -0,0 +1,97 @@
+from pypy.rpython.lltypesystem import lltype, llarena
+from pypy.rpython.memory.gc.base import MovingGCBase
+from pypy.rpython.memory.support import DEFAULT_CHUNK_SIZE
+from pypy.rlib.rarithmetic import LONG_BIT
+from pypy.rlib.objectmodel import we_are_translated
+
+WORD = LONG_BIT // 8
+
+first_gcflag = 1 << (LONG_BIT//2)
+GCFLAG_BIG   = first_gcflag
+
+# ____________________________________________________________
+
+class Gen2GC(MovingGCBase):
+    _alloc_flavor_ = "raw"
+    inline_simple_malloc = True
+    inline_simple_malloc_varsize = True
+    malloc_zero_filled = True
+
+    HDR = lltype.Struct('header', ('tid', lltype.Signed))
+    typeid_is_in_field = 'tid'
+    #withhash_flag_is_in_field = 'tid', _GCFLAG_HASH_BASE * 0x2
+
+    TRANSLATION_PARAMS = {
+        # The size of the nursery.  -1 means "auto", which means that it
+        # will look it up in the env var PYPY_GENERATIONGC_NURSERY and
+        # fall back to half the size of the L2 cache.
+        "nursery_size": -1,
+
+        # The system page size.  Like obmalloc.c, we assume that it is 4K,
+        # which is OK for most systems.
+        "page_size": 4096,
+
+        # The size of an arena.  Arenas are groups of pages allocated
+        # together.
+        "arena_size": 65536*WORD,
+
+        # The maximum size of an object allocated compactly.  All objects
+        # that are larger are just allocated with raw_malloc().
+        "small_request_threshold": 32*WORD,
+        }
+
+    def __init__(self, config, chunk_size=DEFAULT_CHUNK_SIZE,
+                 nursery_size=32*WORD,
+                 page_size=16*WORD,
+                 arena_size=48*WORD,
+                 small_request_threshold=5*WORD):
+        MovingGCBase.__init__(self, config, chunk_size)
+        self.nursery_size = nursery_size
+        self.page_size = page_size
+        self.arena_size = arena_size
+        self.small_request_threshold = small_request_threshold
+
+    def setup(self):
+        pass
+
+# ____________________________________________________________
+
+class Arena(object):
+    _alloc_flavor_ = "raw"
+
+    def __init__(self, arena_size, page_size):
+        self.page_size = page_size
+        self.arena_size = arena_size
+        # 'arena_base' points to the start of malloced memory; it might not
+        # be a page-aligned address
+        self.arena_base = llarena.arena_malloc(self.arena_size, False)
+        if not self.arena_base:
+            raise MemoryError("couldn't allocate the next arena")
+        # 'freepages' points to the first unused page
+        self.freepages = start_of_page(self.arena_base + page_size - 1,
+                                       page_size)
+        # 'nfreepages' is the number of unused pages
+        arena_end = self.arena_base + self.arena_size
+        self.nfreepages = (arena_end - self.freepages) / page_size
+
+# ____________________________________________________________
+# Helpers to go from a pointer to the start of its page
+
+def start_of_page(addr, page_size):
+    """Return the address of the start of the page that contains 'addr'."""
+    if we_are_translated():
+        xxx
+    else:
+        return _start_of_page_untranslated(addr, page_size)
+
+def _start_of_page_untranslated(addr, page_size):
+    assert isinstance(addr, llarena.fakearenaaddress)
+    shift = page_size // 2     # for testing, assuming the whole arena is not
+                               # on a page boundary
+    ofs = ((addr.offset - shift) & ~(page_size-1)) + shift
+    return llarena.fakearenaaddress(addr.arena, ofs)
+
+# ____________________________________________________________
+
+def nursery_size_from_env():
+    return read_from_env('PYPY_GENERATIONGC_NURSERY')

Added: pypy/branch/gen2-gc/pypy/rpython/memory/gc/test/test_gen2.py
==============================================================================
--- (empty file)
+++ pypy/branch/gen2-gc/pypy/rpython/memory/gc/test/test_gen2.py	Mon Sep 13 14:18:55 2010
@@ -0,0 +1,12 @@
+from pypy.rpython.memory.gc import gen2
+
+def test_arena():
+    SHIFT = 4
+    #
+    a = gen2.Arena(SHIFT + 8*20, 8)
+    assert a.freepages == a.arena_base + SHIFT
+    assert a.nfreepages == 20
+    #
+    a = gen2.Arena(SHIFT + 8*20 + 7, 8)
+    assert a.freepages == a.arena_base + SHIFT
+    assert a.nfreepages == 20