def malloc_fixedsize_clear(self,
typeid16,
size,
has_finalizer=False,
is_finalizer_light=False,
contains_weakptr=False):
size_gc_header = self.gcheaderbuilder.size_gc_header
totalsize = size_gc_header + size
result = self.free
if raw_malloc_usage(totalsize) > self.top_of_space - result:
result = self.obtain_free_space(totalsize)
llarena.arena_reserve(result, totalsize)
self.init_gc_object(result, typeid16)
self.free = result + totalsize
#if is_finalizer_light:
# self.objects_with_light_finalizers.append(result + size_gc_header)
#else:
if has_finalizer:
from rpython.rtyper.lltypesystem import rffi
self.objects_with_finalizers.append(result + size_gc_header)
self.objects_with_finalizers.append(rffi.cast(
llmemory.Address, -1))
if contains_weakptr:
self.objects_with_weakrefs.append(result + size_gc_header)
return llmemory.cast_adr_to_ptr(result + size_gc_header,
llmemory.GCREF)
def malloc_fixedsize_clear(self, typeid, size,
has_finalizer=False,
is_finalizer_light=False,
contains_weakptr=False):
if (has_finalizer or
(raw_malloc_usage(size) > self.lb_young_fixedsize and
raw_malloc_usage(size) > self.largest_young_fixedsize)):
# ^^^ we do two size comparisons; the first one appears redundant,
# but it can be constant-folded if 'size' is a constant; then
# it almost always folds down to False, which kills the
# second comparison as well.
ll_assert(not contains_weakptr, "wrong case for mallocing weakref")
# "non-simple" case or object too big: don't use the nursery
return SemiSpaceGC.malloc_fixedsize_clear(self, typeid, size,
has_finalizer,
is_finalizer_light,
contains_weakptr)
size_gc_header = self.gcheaderbuilder.size_gc_header
totalsize = size_gc_header + size
result = self.nursery_free
if raw_malloc_usage(totalsize) > self.nursery_top - result:
result = self.collect_nursery()
llarena.arena_reserve(result, totalsize)
# GCFLAG_NO_YOUNG_PTRS is never set on young objs
self.init_gc_object(result, typeid, flags=0)
self.nursery_free = result + totalsize
if contains_weakptr:
self.young_objects_with_weakrefs.append(result + size_gc_header)
return llmemory.cast_adr_to_ptr(result+size_gc_header, llmemory.GCREF)
def test_address_order():
a = arena_malloc(24, False)
assert eq(a, a)
assert lt(a, a+1)
assert lt(a+5, a+20)
b = arena_malloc(24, False)
if a > b:
a, b = b, a
assert lt(a, b)
assert lt(a+19, b)
assert lt(a, b+19)
c = b + round_up_for_allocation(llmemory.sizeof(lltype.Char))
arena_reserve(c, precomputed_size)
assert lt(b, c)
assert lt(a, c)
assert lt(llmemory.NULL, c)
d = c + llmemory.offsetof(SX, 'x')
assert lt(c, d)
assert lt(b, d)
assert lt(a, d)
assert lt(llmemory.NULL, d)
e = c + precomputed_size
assert lt(d, e)
assert lt(c, e)
assert lt(b, e)
assert lt(a, e)
assert lt(llmemory.NULL, e)
def test_address_order():
a = arena_malloc(24, False)
assert eq(a, a)
assert lt(a, a + 1)
assert lt(a + 5, a + 20)
b = arena_malloc(24, False)
if a > b:
a, b = b, a
assert lt(a, b)
assert lt(a + 19, b)
assert lt(a, b + 19)
c = b + round_up_for_allocation(llmemory.sizeof(lltype.Char))
arena_reserve(c, precomputed_size)
assert lt(b, c)
assert lt(a, c)
assert lt(llmemory.NULL, c)
d = c + llmemory.offsetof(SX, 'x')
assert lt(c, d)
assert lt(b, d)
assert lt(a, d)
assert lt(llmemory.NULL, d)
e = c + precomputed_size
assert lt(d, e)
assert lt(c, e)
assert lt(b, e)
assert lt(a, e)
assert lt(llmemory.NULL, e)
def malloc_fixedsize_clear(self, typeid, size,
has_finalizer=False,
is_finalizer_light=False,
contains_weakptr=False):
if (has_finalizer or
(raw_malloc_usage(size) > self.lb_young_fixedsize and
raw_malloc_usage(size) > self.largest_young_fixedsize)):
# ^^^ we do two size comparisons; the first one appears redundant,
# but it can be constant-folded if 'size' is a constant; then
# it almost always folds down to False, which kills the
# second comparison as well.
ll_assert(not contains_weakptr, "wrong case for mallocing weakref")
# "non-simple" case or object too big: don't use the nursery
return SemiSpaceGC.malloc_fixedsize_clear(self, typeid, size,
has_finalizer,
is_finalizer_light,
contains_weakptr)
size_gc_header = self.gcheaderbuilder.size_gc_header
totalsize = size_gc_header + size
result = self.nursery_free
if raw_malloc_usage(totalsize) > self.nursery_top - result:
result = self.collect_nursery()
llarena.arena_reserve(result, totalsize)
# GCFLAG_NO_YOUNG_PTRS is never set on young objs
self.init_gc_object(result, typeid, flags=0)
self.nursery_free = result + totalsize
if contains_weakptr:
self.young_objects_with_weakrefs.append(result + size_gc_header)
return llmemory.cast_adr_to_ptr(result+size_gc_header, llmemory.GCREF)
def malloc_varsize_collecting_nursery(self, totalsize):
result = self.collect_nursery()
ll_assert(
raw_malloc_usage(totalsize) <= self.nursery_top - result,
"not enough room in malloc_varsize_collecting_nursery()")
llarena.arena_reserve(result, totalsize)
self.nursery_free = result + llarena.round_up_for_allocation(totalsize)
return result
def malloc_varsize_collecting_nursery(self, totalsize):
result = self.collect_nursery()
ll_assert(raw_malloc_usage(totalsize) <= self.nursery_top - result,
"not enough room in malloc_varsize_collecting_nursery()")
llarena.arena_reserve(result, totalsize)
self.nursery_free = result + llarena.round_up_for_allocation(
totalsize)
return result
def malloc(self, size):
nsize = raw_malloc_usage(size)
ll_assert(nsize > 0, "malloc: size is null or negative")
ll_assert(nsize <= self.small_request_threshold,"malloc: size too big")
ll_assert((nsize & (WORD-1)) == 0, "malloc: size is not aligned")
#
result = llarena.arena_malloc(nsize, False)
llarena.arena_reserve(result, size)
self.all_objects.append((result, nsize))
self.total_memory_used += nsize
return result
def malloc(self, size):
nsize = raw_malloc_usage(size)
ll_assert(nsize > 0, "malloc: size is null or negative")
ll_assert(nsize <= self.small_request_threshold,"malloc: size too big")
ll_assert((nsize & (WORD-1)) == 0, "malloc: size is not aligned")
#
result = llarena.arena_malloc(nsize, False)
llarena.arena_reserve(result, size)
self.all_objects.append((result, nsize))
self.total_memory_used += nsize
return result
def test_shrink_obj():
from rpython.memory.gcheader import GCHeaderBuilder
HDR = lltype.Struct('HDR', ('h', lltype.Signed))
gcheaderbuilder = GCHeaderBuilder(HDR)
size_gc_header = gcheaderbuilder.size_gc_header
S = lltype.GcStruct('S', ('x', lltype.Signed),
('a', lltype.Array(lltype.Signed)))
myarenasize = 200
a = arena_malloc(myarenasize, False)
arena_reserve(a, size_gc_header + llmemory.sizeof(S, 10))
arena_shrink_obj(a, size_gc_header + llmemory.sizeof(S, 5))
arena_reset(a, size_gc_header + llmemory.sizeof(S, 5), False)
def test_address_eq_as_int():
a = arena_malloc(50, False)
arena_reserve(a, precomputed_size)
p = llmemory.cast_adr_to_ptr(a, SPTR)
a1 = llmemory.cast_ptr_to_adr(p)
assert a == a1
assert not (a != a1)
assert (a+1) != a1
assert not ((a+1) == a1)
py.test.skip("cast_adr_to_int() is hard to get consistent")
assert llmemory.cast_adr_to_int(a) == llmemory.cast_adr_to_int(a1)
assert llmemory.cast_adr_to_int(a+1) == llmemory.cast_adr_to_int(a1) + 1
def test_address_eq_as_int():
a = arena_malloc(50, False)
arena_reserve(a, precomputed_size)
p = llmemory.cast_adr_to_ptr(a, SPTR)
a1 = llmemory.cast_ptr_to_adr(p)
assert a == a1
assert not (a != a1)
assert (a + 1) != a1
assert not ((a + 1) == a1)
py.test.skip("cast_adr_to_int() is hard to get consistent")
assert llmemory.cast_adr_to_int(a) == llmemory.cast_adr_to_int(a1)
assert llmemory.cast_adr_to_int(a + 1) == llmemory.cast_adr_to_int(a1) + 1
def test_shrink_obj():
from rpython.memory.gcheader import GCHeaderBuilder
HDR = lltype.Struct('HDR', ('h', lltype.Signed))
gcheaderbuilder = GCHeaderBuilder(HDR)
size_gc_header = gcheaderbuilder.size_gc_header
S = lltype.GcStruct('S', ('x', lltype.Signed),
('a', lltype.Array(lltype.Signed)))
myarenasize = 200
a = arena_malloc(myarenasize, False)
arena_reserve(a, size_gc_header + llmemory.sizeof(S, 10))
arena_shrink_obj(a, size_gc_header + llmemory.sizeof(S, 5))
arena_reset(a, size_gc_header + llmemory.sizeof(S, 5), False)
def free_page(self, page):
"""Free a whole page."""
#
# Insert the freed page in the arena's 'freepages' list.
# If nfreepages == totalpages, then it will be freed at the
# end of mass_free().
arena = page.arena
arena.nfreepages += 1
pageaddr = llmemory.cast_ptr_to_adr(page)
pageaddr = llarena.getfakearenaaddress(pageaddr)
llarena.arena_reset(pageaddr, self.page_size, 0)
llarena.arena_reserve(pageaddr, llmemory.sizeof(llmemory.Address))
pageaddr.address[0] = arena.freepages
arena.freepages = pageaddr
def allocate_new_page(self, size_class):
"""Allocate and return a new page for the given size_class."""
#
# Allocate a new arena if needed.
if self.current_arena == ARENA_NULL:
self.allocate_new_arena()
#
# The result is simply 'current_arena.freepages'.
arena = self.current_arena
result = arena.freepages
if arena.nfreepages > 0:
#
# The 'result' was part of the chained list; read the next.
arena.nfreepages -= 1
freepages = result.address[0]
llarena.arena_reset(result,
llmemory.sizeof(llmemory.Address),
0)
#
else:
# The 'result' is part of the uninitialized pages.
ll_assert(self.num_uninitialized_pages > 0,
"fully allocated arena found in self.current_arena")
self.num_uninitialized_pages -= 1
if self.num_uninitialized_pages > 0:
freepages = result + self.page_size
else:
freepages = NULL
#
arena.freepages = freepages
if freepages == NULL:
# This was the last page, so put the arena away into
# arenas_lists[0].
ll_assert(arena.nfreepages == 0,
"freepages == NULL but nfreepages > 0")
arena.nextarena = self.arenas_lists[0]
self.arenas_lists[0] = arena
self.current_arena = ARENA_NULL
#
# Initialize the fields of the resulting page
llarena.arena_reserve(result, llmemory.sizeof(PAGE_HEADER))
page = llmemory.cast_adr_to_ptr(result, PAGE_PTR)
page.arena = arena
page.nfree = 0
page.freeblock = result + self.hdrsize
page.nextpage = PAGE_NULL
ll_assert(self.page_for_size[size_class] == PAGE_NULL,
"allocate_new_page() called but a page is already waiting")
self.page_for_size[size_class] = page
return page
def free_page(self, page):
"""Free a whole page."""
#
# Insert the freed page in the arena's 'freepages' list.
# If nfreepages == totalpages, then it will be freed at the
# end of mass_free().
arena = page.arena
arena.nfreepages += 1
pageaddr = llmemory.cast_ptr_to_adr(page)
pageaddr = llarena.getfakearenaaddress(pageaddr)
llarena.arena_reset(pageaddr, self.page_size, 0)
llarena.arena_reserve(pageaddr, llmemory.sizeof(llmemory.Address))
pageaddr.address[0] = arena.freepages
arena.freepages = pageaddr
def test_arena_protect():
a = arena_malloc(100, False)
S = lltype.Struct('S', ('x', lltype.Signed))
arena_reserve(a, llmemory.sizeof(S))
p = llmemory.cast_adr_to_ptr(a, lltype.Ptr(S))
p.x = 123
assert p.x == 123
arena_protect(a, 100, True)
py.test.raises(ArenaError, arena_reserve, a + 48, llmemory.sizeof(S))
py.test.raises(RuntimeError, "p.x")
py.test.raises(RuntimeError, "p.x = 124")
arena_protect(a, 100, False)
assert p.x == 123
p.x = 125
assert p.x == 125
def test_arena_protect():
a = arena_malloc(100, False)
S = lltype.Struct('S', ('x', lltype.Signed))
arena_reserve(a, llmemory.sizeof(S))
p = llmemory.cast_adr_to_ptr(a, lltype.Ptr(S))
p.x = 123
assert p.x == 123
arena_protect(a, 100, True)
py.test.raises(ArenaError, arena_reserve, a + 48, llmemory.sizeof(S))
py.test.raises(RuntimeError, "p.x")
py.test.raises(RuntimeError, "p.x = 124")
arena_protect(a, 100, False)
assert p.x == 123
p.x = 125
assert p.x == 125
def test_look_inside_object():
# this code is also used in translation tests below
myarenasize = 50
a = arena_malloc(myarenasize, False)
b = a + round_up_for_allocation(llmemory.sizeof(lltype.Char))
arena_reserve(b, precomputed_size)
(b + llmemory.offsetof(SX, 'x')).signed[0] = 123
assert llmemory.cast_adr_to_ptr(b, SPTR).x == 123
llmemory.cast_adr_to_ptr(b, SPTR).x += 1
assert (b + llmemory.offsetof(SX, 'x')).signed[0] == 124
arena_reset(a, myarenasize, True)
arena_reserve(b, round_up_for_allocation(llmemory.sizeof(SX)))
assert llmemory.cast_adr_to_ptr(b, SPTR).x == 0
arena_free(a)
return 42
def test_look_inside_object():
# this code is also used in translation tests below
myarenasize = 50
a = arena_malloc(myarenasize, False)
b = a + round_up_for_allocation(llmemory.sizeof(lltype.Char))
arena_reserve(b, precomputed_size)
(b + llmemory.offsetof(SX, 'x')).signed[0] = 123
assert llmemory.cast_adr_to_ptr(b, SPTR).x == 123
llmemory.cast_adr_to_ptr(b, SPTR).x += 1
assert (b + llmemory.offsetof(SX, 'x')).signed[0] == 124
arena_reset(a, myarenasize, True)
arena_reserve(b, round_up_for_allocation(llmemory.sizeof(SX)))
assert llmemory.cast_adr_to_ptr(b, SPTR).x == 0
arena_free(a)
return 42
def allocate_new_page(self, size_class):
"""Allocate and return a new page for the given size_class."""
#
# Allocate a new arena if needed.
if self.current_arena == ARENA_NULL:
self.allocate_new_arena()
#
# The result is simply 'current_arena.freepages'.
arena = self.current_arena
result = arena.freepages
if arena.nfreepages > 0:
#
# The 'result' was part of the chained list; read the next.
arena.nfreepages -= 1
freepages = result.address[0]
llarena.arena_reset(result, llmemory.sizeof(llmemory.Address), 0)
#
else:
# The 'result' is part of the uninitialized pages.
ll_assert(self.num_uninitialized_pages > 0,
"fully allocated arena found in self.current_arena")
self.num_uninitialized_pages -= 1
if self.num_uninitialized_pages > 0:
freepages = result + self.page_size
else:
freepages = NULL
#
arena.freepages = freepages
if freepages == NULL:
# This was the last page, so put the arena away into
# arenas_lists[0].
ll_assert(arena.nfreepages == 0,
"freepages == NULL but nfreepages > 0")
arena.nextarena = self.arenas_lists[0]
self.arenas_lists[0] = arena
self.current_arena = ARENA_NULL
#
# Initialize the fields of the resulting page
llarena.arena_reserve(result, llmemory.sizeof(PAGE_HEADER))
page = llmemory.cast_adr_to_ptr(result, PAGE_PTR)
page.arena = arena
page.nfree = 0
page.freeblock = result + self.hdrsize
page.nextpage = PAGE_NULL
ll_assert(self.page_for_size[size_class] == PAGE_NULL,
"allocate_new_page() called but a page is already waiting")
self.page_for_size[size_class] = page
return page
def malloc_varsize_clear(self, typeid16, length, size, itemsize,
offset_to_length):
size_gc_header = self.gcheaderbuilder.size_gc_header
nonvarsize = size_gc_header + size
try:
varsize = ovfcheck(itemsize * length)
totalsize = ovfcheck(nonvarsize + varsize)
except OverflowError:
raise memoryError
result = self.free
if raw_malloc_usage(totalsize) > self.top_of_space - result:
result = self.obtain_free_space(totalsize)
llarena.arena_reserve(result, totalsize)
self.init_gc_object(result, typeid16)
(result + size_gc_header + offset_to_length).signed[0] = length
self.free = result + llarena.round_up_for_allocation(totalsize)
return llmemory.cast_adr_to_ptr(result+size_gc_header, llmemory.GCREF)
def _make_a_copy_with_tid(self, obj, objsize, tid):
totalsize = self.size_gc_header() + objsize
newaddr = self.free
llarena.arena_reserve(newaddr, totalsize)
raw_memcopy(obj - self.size_gc_header(), newaddr, totalsize)
if tid & GCFLAG_HASHMASK:
hash = self._get_object_hash(obj, objsize, tid)
llarena.arena_reserve(newaddr + totalsize,
llmemory.sizeof(lltype.Signed))
(newaddr + totalsize).signed[0] = hash
tid |= GC_HASH_HASFIELD
totalsize += llmemory.sizeof(lltype.Signed)
self.free += totalsize
newhdr = llmemory.cast_adr_to_ptr(newaddr, lltype.Ptr(self.HDR))
newhdr.tid = tid
newobj = newaddr + self.size_gc_header()
return newobj
def fn(argv):
testrun = int(argv[1])
a = arena_malloc(65536, False)
arena_reserve(a, llmemory.sizeof(S))
p = llmemory.cast_adr_to_ptr(a + 23432, lltype.Ptr(S))
p.x = 123
assert p.x == 123
arena_protect(a, 65536, True)
result = 0
if testrun == 1:
print p.x # segfault
if testrun == 2:
p.x = 124 # segfault
arena_protect(a, 65536, False)
p.x += 10
print p.x
return 0
def fn(argv):
testrun = int(argv[1])
a = arena_malloc(65536, False)
arena_reserve(a, llmemory.sizeof(S))
p = llmemory.cast_adr_to_ptr(a + 23432, lltype.Ptr(S))
p.x = 123
assert p.x == 123
arena_protect(a, 65536, True)
result = 0
if testrun == 1:
print p.x # segfault
if testrun == 2:
p.x = 124 # segfault
arena_protect(a, 65536, False)
p.x += 10
print p.x
return 0
def _make_a_copy_with_tid(self, obj, objsize, tid):
totalsize = self.size_gc_header() + objsize
newaddr = self.free
llarena.arena_reserve(newaddr, totalsize)
raw_memcopy(obj - self.size_gc_header(), newaddr, totalsize)
if tid & GCFLAG_HASHMASK:
hash = self._get_object_hash(obj, objsize, tid)
llarena.arena_reserve(newaddr + totalsize,
llmemory.sizeof(lltype.Signed))
(newaddr + totalsize).signed[0] = hash
tid |= GC_HASH_HASFIELD
totalsize += llmemory.sizeof(lltype.Signed)
self.free += totalsize
newhdr = llmemory.cast_adr_to_ptr(newaddr, lltype.Ptr(self.HDR))
newhdr.tid = tid
newobj = newaddr + self.size_gc_header()
return newobj
def set_forwarding_address(self, obj, newobj, objsize):
# To mark an object as forwarded, we set the GCFLAG_FORWARDED and
# overwrite the object with a FORWARDSTUB. Doing so is a bit
# long-winded on llarena, but it all melts down to two memory
# writes after translation to C.
size_gc_header = self.size_gc_header()
stubsize = llmemory.sizeof(self.FORWARDSTUB)
tid = self.header(obj).tid
ll_assert(tid & GCFLAG_EXTERNAL == 0, "unexpected GCFLAG_EXTERNAL")
ll_assert(tid & GCFLAG_FORWARDED == 0, "unexpected GCFLAG_FORWARDED")
# replace the object at 'obj' with a FORWARDSTUB.
hdraddr = obj - size_gc_header
llarena.arena_reset(hdraddr, size_gc_header + objsize, False)
llarena.arena_reserve(hdraddr, size_gc_header + stubsize)
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(self.HDR))
hdr.tid = tid | GCFLAG_FORWARDED
stub = llmemory.cast_adr_to_ptr(obj, self.FORWARDSTUBPTR)
stub.forw = newobj
def malloc_varsize_clear(self, typeid16, length, size, itemsize,
offset_to_length):
size_gc_header = self.gcheaderbuilder.size_gc_header
nonvarsize = size_gc_header + size
try:
varsize = ovfcheck(itemsize * length)
totalsize = ovfcheck(nonvarsize + varsize)
except OverflowError:
raise memoryError
result = self.free
if raw_malloc_usage(totalsize) > self.top_of_space - result:
result = self.obtain_free_space(totalsize)
llarena.arena_reserve(result, totalsize)
self.init_gc_object(result, typeid16)
(result + size_gc_header + offset_to_length).signed[0] = length
self.free = result + llarena.round_up_for_allocation(totalsize)
return llmemory.cast_adr_to_ptr(result + size_gc_header,
llmemory.GCREF)
def set_forwarding_address(self, obj, newobj, objsize):
# To mark an object as forwarded, we set the GCFLAG_FORWARDED and
# overwrite the object with a FORWARDSTUB. Doing so is a bit
# long-winded on llarena, but it all melts down to two memory
# writes after translation to C.
size_gc_header = self.size_gc_header()
stubsize = llmemory.sizeof(self.FORWARDSTUB)
tid = self.header(obj).tid
ll_assert(tid & GCFLAG_EXTERNAL == 0, "unexpected GCFLAG_EXTERNAL")
ll_assert(tid & GCFLAG_FORWARDED == 0, "unexpected GCFLAG_FORWARDED")
# replace the object at 'obj' with a FORWARDSTUB.
hdraddr = obj - size_gc_header
llarena.arena_reset(hdraddr, size_gc_header + objsize, False)
llarena.arena_reserve(hdraddr, size_gc_header + stubsize)
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(self.HDR))
hdr.tid = tid | GCFLAG_FORWARDED
stub = llmemory.cast_adr_to_ptr(obj, self.FORWARDSTUBPTR)
stub.forw = newobj
def malloc_varsize_clear(self, typeid, length, size, itemsize,
offset_to_length):
# Only use the nursery if there are not too many items.
if not raw_malloc_usage(itemsize):
too_many_items = False
else:
# The following line is usually constant-folded because both
# min_nursery_size and itemsize are constants (the latter
# due to inlining).
maxlength_for_minimal_nursery = (self.min_nursery_size // 4 //
raw_malloc_usage(itemsize))
# The actual maximum length for our nursery depends on how
# many times our nursery is bigger than the minimal size.
# The computation is done in this roundabout way so that
# only the only remaining computation is the following
# shift.
maxlength = maxlength_for_minimal_nursery << self.nursery_scale
too_many_items = length > maxlength
if (too_many_items or
(raw_malloc_usage(size) > self.lb_young_var_basesize
and raw_malloc_usage(size) > self.largest_young_var_basesize)):
# ^^^ we do two size comparisons; the first one appears redundant,
# but it can be constant-folded if 'size' is a constant; then
# it almost always folds down to False, which kills the
# second comparison as well.
return SemiSpaceGC.malloc_varsize_clear(self, typeid, length, size,
itemsize, offset_to_length)
# with the above checks we know now that totalsize cannot be more
# than about half of the nursery size; in particular, the + and *
# cannot overflow
size_gc_header = self.gcheaderbuilder.size_gc_header
totalsize = size_gc_header + size + itemsize * length
result = self.nursery_free
if raw_malloc_usage(totalsize) > self.nursery_top - result:
result = self.collect_nursery()
llarena.arena_reserve(result, totalsize)
# GCFLAG_NO_YOUNG_PTRS is never set on young objs
self.init_gc_object(result, typeid, flags=0)
(result + size_gc_header + offset_to_length).signed[0] = length
self.nursery_free = result + llarena.round_up_for_allocation(totalsize)
return llmemory.cast_adr_to_ptr(result + size_gc_header,
llmemory.GCREF)
def malloc_varsize_clear(self, typeid, length, size, itemsize,
offset_to_length):
# Only use the nursery if there are not too many items.
if not raw_malloc_usage(itemsize):
too_many_items = False
else:
# The following line is usually constant-folded because both
# min_nursery_size and itemsize are constants (the latter
# due to inlining).
maxlength_for_minimal_nursery = (self.min_nursery_size // 4 //
raw_malloc_usage(itemsize))
# The actual maximum length for our nursery depends on how
# many times our nursery is bigger than the minimal size.
# The computation is done in this roundabout way so that
# only the only remaining computation is the following
# shift.
maxlength = maxlength_for_minimal_nursery << self.nursery_scale
too_many_items = length > maxlength
if (too_many_items or
(raw_malloc_usage(size) > self.lb_young_var_basesize and
raw_malloc_usage(size) > self.largest_young_var_basesize)):
# ^^^ we do two size comparisons; the first one appears redundant,
# but it can be constant-folded if 'size' is a constant; then
# it almost always folds down to False, which kills the
# second comparison as well.
return SemiSpaceGC.malloc_varsize_clear(self, typeid, length, size,
itemsize, offset_to_length)
# with the above checks we know now that totalsize cannot be more
# than about half of the nursery size; in particular, the + and *
# cannot overflow
size_gc_header = self.gcheaderbuilder.size_gc_header
totalsize = size_gc_header + size + itemsize * length
result = self.nursery_free
if raw_malloc_usage(totalsize) > self.nursery_top - result:
result = self.collect_nursery()
llarena.arena_reserve(result, totalsize)
# GCFLAG_NO_YOUNG_PTRS is never set on young objs
self.init_gc_object(result, typeid, flags=0)
(result + size_gc_header + offset_to_length).signed[0] = length
self.nursery_free = result + llarena.round_up_for_allocation(totalsize)
return llmemory.cast_adr_to_ptr(result+size_gc_header, llmemory.GCREF)
def malloc_fixedsize_clear(self, typeid16, size,
has_finalizer=False,
is_finalizer_light=False,
contains_weakptr=False):
size_gc_header = self.gcheaderbuilder.size_gc_header
totalsize = size_gc_header + size
result = self.free
if raw_malloc_usage(totalsize) > self.top_of_space - result:
result = self.obtain_free_space(totalsize)
llarena.arena_reserve(result, totalsize)
self.init_gc_object(result, typeid16)
self.free = result + totalsize
#if is_finalizer_light:
# self.objects_with_light_finalizers.append(result + size_gc_header)
#else:
if has_finalizer:
self.objects_with_finalizers.append(result + size_gc_header)
if contains_weakptr:
self.objects_with_weakrefs.append(result + size_gc_header)
return llmemory.cast_adr_to_ptr(result+size_gc_header, llmemory.GCREF)
def malloc(self, size):
"""Allocate a block from a page in an arena."""
nsize = llmemory.raw_malloc_usage(size)
ll_assert(nsize > 0, "malloc: size is null or negative")
ll_assert(nsize <= self.small_request_threshold,"malloc: size too big")
ll_assert((nsize & (WORD-1)) == 0, "malloc: size is not aligned")
self.total_memory_used += r_uint(nsize)
#
# Get the page to use from the size
size_class = nsize >> WORD_POWER_2
page = self.page_for_size[size_class]
if page == PAGE_NULL:
page = self.allocate_new_page(size_class)
#
# The result is simply 'page.freeblock'
result = page.freeblock
if page.nfree > 0:
#
# The 'result' was part of the chained list; read the next.
page.nfree -= 1
freeblock = result.address[0]
llarena.arena_reset(result,
llmemory.sizeof(llmemory.Address),
0)
#
else:
# The 'result' is part of the uninitialized blocks.
freeblock = result + nsize
#
page.freeblock = freeblock
#
pageaddr = llarena.getfakearenaaddress(llmemory.cast_ptr_to_adr(page))
if freeblock - pageaddr > self.page_size - nsize:
# This was the last free block, so unlink the page from the
# chained list and put it in the 'full_page_for_size' list.
self.page_for_size[size_class] = page.nextpage
page.nextpage = self.full_page_for_size[size_class]
self.full_page_for_size[size_class] = page
#
llarena.arena_reserve(result, _dummy_size(size))
return result
def malloc(self, size):
"""Allocate a block from a page in an arena."""
nsize = llmemory.raw_malloc_usage(size)
ll_assert(nsize > 0, "malloc: size is null or negative")
ll_assert(nsize <= self.small_request_threshold,
"malloc: size too big")
ll_assert((nsize & (WORD - 1)) == 0, "malloc: size is not aligned")
self.total_memory_used += r_uint(nsize)
#
# Get the page to use from the size
size_class = nsize >> WORD_POWER_2
page = self.page_for_size[size_class]
if page == PAGE_NULL:
page = self.allocate_new_page(size_class)
#
# The result is simply 'page.freeblock'
result = page.freeblock
if page.nfree > 0:
#
# The 'result' was part of the chained list; read the next.
page.nfree -= 1
freeblock = result.address[0]
llarena.arena_reset(result, llmemory.sizeof(llmemory.Address), 0)
#
else:
# The 'result' is part of the uninitialized blocks.
freeblock = result + nsize
#
page.freeblock = freeblock
#
pageaddr = llarena.getfakearenaaddress(llmemory.cast_ptr_to_adr(page))
if freeblock - pageaddr > self.page_size - nsize:
# This was the last free block, so unlink the page from the
# chained list and put it in the 'full_page_for_size' list.
self.page_for_size[size_class] = page.nextpage
page.nextpage = self.full_page_for_size[size_class]
self.full_page_for_size[size_class] = page
#
llarena.arena_reserve(result, _dummy_size(size))
return result
def link(pageaddr, size_class, size_block, nblocks, nusedblocks, step=1):
assert step in (1, 2)
llarena.arena_reserve(pageaddr, llmemory.sizeof(PAGE_HEADER))
page = llmemory.cast_adr_to_ptr(pageaddr, PAGE_PTR)
if step == 1:
page.nfree = 0
nuninitialized = nblocks - nusedblocks
else:
page.nfree = nusedblocks
nuninitialized = nblocks - 2*nusedblocks
page.freeblock = pageaddr + hdrsize + nusedblocks * size_block
if nusedblocks < nblocks:
chainedlists = ac.page_for_size
else:
chainedlists = ac.full_page_for_size
page.nextpage = chainedlists[size_class]
page.arena = ac.current_arena
chainedlists[size_class] = page
if fill_with_objects:
for i in range(0, nusedblocks*step, step):
objaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(objaddr, _dummy_size(size_block))
if step == 2:
prev = 'page.freeblock'
for i in range(1, nusedblocks*step, step):
holeaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(holeaddr,
llmemory.sizeof(llmemory.Address))
exec '%s = holeaddr' % prev in globals(), locals()
prevhole = holeaddr
prev = 'prevhole.address[0]'
endaddr = pageaddr + hdrsize + 2*nusedblocks * size_block
exec '%s = endaddr' % prev in globals(), locals()
assert ac._nuninitialized(page, size_class) == nuninitialized
def link(pageaddr, size_class, size_block, nblocks, nusedblocks, step=1):
assert step in (1, 2)
llarena.arena_reserve(pageaddr, llmemory.sizeof(PAGE_HEADER))
page = llmemory.cast_adr_to_ptr(pageaddr, PAGE_PTR)
if step == 1:
page.nfree = 0
nuninitialized = nblocks - nusedblocks
else:
page.nfree = nusedblocks
nuninitialized = nblocks - 2 * nusedblocks
page.freeblock = pageaddr + hdrsize + nusedblocks * size_block
if nusedblocks < nblocks:
chainedlists = ac.page_for_size
else:
chainedlists = ac.full_page_for_size
page.nextpage = chainedlists[size_class]
page.arena = ac.current_arena
chainedlists[size_class] = page
if fill_with_objects:
for i in range(0, nusedblocks * step, step):
objaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(objaddr, _dummy_size(size_block))
if step == 2:
prev = 'page.freeblock'
for i in range(1, nusedblocks * step, step):
holeaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(holeaddr,
llmemory.sizeof(llmemory.Address))
exec('%s = holeaddr' % prev, globals(), locals())
prevhole = holeaddr
prev = 'prevhole.address[0]'
endaddr = pageaddr + hdrsize + 2 * nusedblocks * size_block
exec('%s = endaddr' % prev, globals(), locals())
assert ac._nuninitialized(page, size_class) == nuninitialized
def test_replace_object_with_stub():
from rpython.memory.gcheader import GCHeaderBuilder
HDR = lltype.Struct('HDR', ('x', lltype.Signed))
S = lltype.GcStruct('S', ('y', lltype.Signed), ('z', lltype.Signed))
STUB = lltype.GcStruct('STUB', ('t', lltype.Char))
gcheaderbuilder = GCHeaderBuilder(HDR)
size_gc_header = gcheaderbuilder.size_gc_header
ssize = llmemory.raw_malloc_usage(llmemory.sizeof(S))
a = arena_malloc(13*ssize, True)
hdraddr = a + 3*ssize
arena_reserve(hdraddr, size_gc_header + llmemory.sizeof(S))
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(HDR))
hdr.x = 42
obj = llmemory.cast_adr_to_ptr(hdraddr + size_gc_header, lltype.Ptr(S))
obj.y = -5
obj.z = -6
hdraddr = llmemory.cast_ptr_to_adr(obj) - size_gc_header
arena_reset(hdraddr, size_gc_header + llmemory.sizeof(S), False)
arena_reserve(hdraddr, size_gc_header + llmemory.sizeof(STUB))
# check that it possible to reach the newly reserved HDR+STUB
# via the header of the old 'obj' pointer, both via the existing
# 'hdraddr':
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(HDR))
hdr.x = 46
stub = llmemory.cast_adr_to_ptr(hdraddr + size_gc_header, lltype.Ptr(STUB))
stub.t = '!'
# and via a (now-invalid) pointer to the old 'obj': (this is needed
# because during a garbage collection there are still pointers to
# the old 'obj' around to be fixed)
hdraddr = llmemory.cast_ptr_to_adr(obj) - size_gc_header
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(HDR))
assert hdr.x == 46
stub = llmemory.cast_adr_to_ptr(hdraddr + size_gc_header,
lltype.Ptr(STUB))
assert stub.t == '!'
def malloc_varsize_clear(self, typeid, length, size, itemsize,
offset_to_length):
size_gc_header = self.gcheaderbuilder.size_gc_header
nonvarsize = size_gc_header + size
# Compute the maximal length that makes the object still
# below 'nonlarge_max'. All the following logic is usually
# constant-folded because self.nonlarge_max, size and itemsize
# are all constants (the arguments are constant due to
# inlining) and self.has_gcptr_in_varsize() is constant-folded.
if self.has_gcptr_in_varsize(typeid):
nonlarge_max = self.nonlarge_gcptrs_max
else:
nonlarge_max = self.nonlarge_max
if not raw_malloc_usage(itemsize):
too_many_items = raw_malloc_usage(nonvarsize) > nonlarge_max
else:
maxlength = nonlarge_max - raw_malloc_usage(nonvarsize)
maxlength = maxlength // raw_malloc_usage(itemsize)
too_many_items = length > maxlength
if not too_many_items:
# With the above checks we know now that totalsize cannot be more
# than 'nonlarge_max'; in particular, the + and * cannot overflow.
# Let's try to fit the object in the nursery.
totalsize = nonvarsize + itemsize * length
result = self.nursery_free
if raw_malloc_usage(totalsize) <= self.nursery_top - result:
llarena.arena_reserve(result, totalsize)
# GCFLAG_NO_YOUNG_PTRS is never set on young objs
self.init_gc_object(result, typeid, flags=0)
(result + size_gc_header + offset_to_length).signed[0] = length
self.nursery_free = result + llarena.round_up_for_allocation(
totalsize)
return llmemory.cast_adr_to_ptr(result+size_gc_header,
llmemory.GCREF)
return self.malloc_varsize_slowpath(typeid, length)
def test_replace_object_with_stub():
from rpython.memory.gcheader import GCHeaderBuilder
HDR = lltype.Struct('HDR', ('x', lltype.Signed))
S = lltype.GcStruct('S', ('y', lltype.Signed), ('z', lltype.Signed))
STUB = lltype.GcStruct('STUB', ('t', lltype.Char))
gcheaderbuilder = GCHeaderBuilder(HDR)
size_gc_header = gcheaderbuilder.size_gc_header
ssize = llmemory.raw_malloc_usage(llmemory.sizeof(S))
a = arena_malloc(13 * ssize, True)
hdraddr = a + 3 * ssize
arena_reserve(hdraddr, size_gc_header + llmemory.sizeof(S))
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(HDR))
hdr.x = 42
obj = llmemory.cast_adr_to_ptr(hdraddr + size_gc_header, lltype.Ptr(S))
obj.y = -5
obj.z = -6
hdraddr = llmemory.cast_ptr_to_adr(obj) - size_gc_header
arena_reset(hdraddr, size_gc_header + llmemory.sizeof(S), False)
arena_reserve(hdraddr, size_gc_header + llmemory.sizeof(STUB))
# check that it possible to reach the newly reserved HDR+STUB
# via the header of the old 'obj' pointer, both via the existing
# 'hdraddr':
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(HDR))
hdr.x = 46
stub = llmemory.cast_adr_to_ptr(hdraddr + size_gc_header, lltype.Ptr(STUB))
stub.t = '!'
# and via a (now-invalid) pointer to the old 'obj': (this is needed
# because during a garbage collection there are still pointers to
# the old 'obj' around to be fixed)
hdraddr = llmemory.cast_ptr_to_adr(obj) - size_gc_header
hdr = llmemory.cast_adr_to_ptr(hdraddr, lltype.Ptr(HDR))
assert hdr.x == 46
stub = llmemory.cast_adr_to_ptr(hdraddr + size_gc_header, lltype.Ptr(STUB))
assert stub.t == '!'
def malloc_varsize_clear(self, typeid, length, size, itemsize,
offset_to_length):
size_gc_header = self.gcheaderbuilder.size_gc_header
nonvarsize = size_gc_header + size
# Compute the maximal length that makes the object still
# below 'nonlarge_max'. All the following logic is usually
# constant-folded because self.nonlarge_max, size and itemsize
# are all constants (the arguments are constant due to
# inlining) and self.has_gcptr_in_varsize() is constant-folded.
if self.has_gcptr_in_varsize(typeid):
nonlarge_max = self.nonlarge_gcptrs_max
else:
nonlarge_max = self.nonlarge_max
if not raw_malloc_usage(itemsize):
too_many_items = raw_malloc_usage(nonvarsize) > nonlarge_max
else:
maxlength = nonlarge_max - raw_malloc_usage(nonvarsize)
maxlength = maxlength // raw_malloc_usage(itemsize)
too_many_items = length > maxlength
if not too_many_items:
# With the above checks we know now that totalsize cannot be more
# than 'nonlarge_max'; in particular, the + and * cannot overflow.
# Let's try to fit the object in the nursery.
totalsize = nonvarsize + itemsize * length
result = self.nursery_free
if raw_malloc_usage(totalsize) <= self.nursery_top - result:
llarena.arena_reserve(result, totalsize)
# GCFLAG_NO_YOUNG_PTRS is never set on young objs
self.init_gc_object(result, typeid, flags=0)
(result + size_gc_header + offset_to_length).signed[0] = length
self.nursery_free = result + llarena.round_up_for_allocation(
totalsize)
return llmemory.cast_adr_to_ptr(result + size_gc_header,
llmemory.GCREF)
return self.malloc_varsize_slowpath(typeid, length)
def arena_collection_for_test(pagesize, pagelayout, fill_with_objects=False):
assert " " not in pagelayout.rstrip(" ")
nb_pages = len(pagelayout)
arenasize = pagesize * (nb_pages + 1) - 1
ac = ArenaCollection(arenasize, pagesize, 9*WORD)
#
def link(pageaddr, size_class, size_block, nblocks, nusedblocks, step=1):
assert step in (1, 2)
llarena.arena_reserve(pageaddr, llmemory.sizeof(PAGE_HEADER))
page = llmemory.cast_adr_to_ptr(pageaddr, PAGE_PTR)
if step == 1:
page.nfree = 0
nuninitialized = nblocks - nusedblocks
else:
page.nfree = nusedblocks
nuninitialized = nblocks - 2*nusedblocks
page.freeblock = pageaddr + hdrsize + nusedblocks * size_block
if nusedblocks < nblocks:
chainedlists = ac.page_for_size
else:
chainedlists = ac.full_page_for_size
page.nextpage = chainedlists[size_class]
page.arena = ac.current_arena
chainedlists[size_class] = page
if fill_with_objects:
for i in range(0, nusedblocks*step, step):
objaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(objaddr, _dummy_size(size_block))
if step == 2:
prev = 'page.freeblock'
for i in range(1, nusedblocks*step, step):
holeaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(holeaddr,
llmemory.sizeof(llmemory.Address))
exec '%s = holeaddr' % prev in globals(), locals()
prevhole = holeaddr
prev = 'prevhole.address[0]'
endaddr = pageaddr + hdrsize + 2*nusedblocks * size_block
exec '%s = endaddr' % prev in globals(), locals()
assert ac._nuninitialized(page, size_class) == nuninitialized
#
ac.allocate_new_arena()
num_initialized_pages = len(pagelayout.rstrip(" "))
ac._startpageaddr = ac.current_arena.freepages
if pagelayout.endswith(" "):
ac.current_arena.freepages += pagesize * num_initialized_pages
else:
ac.current_arena.freepages = NULL
ac.num_uninitialized_pages -= num_initialized_pages
#
for i in reversed(range(num_initialized_pages)):
pageaddr = pagenum(ac, i)
c = pagelayout[i]
if '1' <= c <= '9': # a partially used page (1 block free)
size_class = int(c)
size_block = WORD * size_class
nblocks = (pagesize - hdrsize) // size_block
link(pageaddr, size_class, size_block, nblocks, nblocks-1)
elif c == '.': # a free, but initialized, page
llarena.arena_reserve(pageaddr, llmemory.sizeof(llmemory.Address))
pageaddr.address[0] = ac.current_arena.freepages
ac.current_arena.freepages = pageaddr
ac.current_arena.nfreepages += 1
elif c == '#': # a random full page, in the list 'full_pages'
size_class = fill_with_objects or 1
size_block = WORD * size_class
nblocks = (pagesize - hdrsize) // size_block
link(pageaddr, size_class, size_block, nblocks, nblocks)
elif c == '/': # a page 1/3 allocated, 1/3 freed, 1/3 uninit objs
size_class = fill_with_objects or 1
size_block = WORD * size_class
nblocks = (pagesize - hdrsize) // size_block
link(pageaddr, size_class, size_block, nblocks, nblocks // 3,
step=2)
#
ac.allocate_new_arena = lambda: should_not_allocate_new_arenas
return ac
def test_arena_new_view():
a = arena_malloc(50, False)
arena_reserve(a, precomputed_size)
# we can now allocate the same space in new view
b = arena_new_view(a)
arena_reserve(b, precomputed_size)
def test_arena():
S = lltype.Struct('S', ('x', lltype.Signed))
SPTR = lltype.Ptr(S)
ssize = llmemory.raw_malloc_usage(llmemory.sizeof(S))
myarenasize = 2*ssize+1
a = arena_malloc(myarenasize, False)
assert a != llmemory.NULL
assert a + 3 != llmemory.NULL
arena_reserve(a, llmemory.sizeof(S))
s1_ptr1 = cast_adr_to_ptr(a, SPTR)
s1_ptr1.x = 1
s1_ptr2 = cast_adr_to_ptr(a, SPTR)
assert s1_ptr2.x == 1
assert s1_ptr1 == s1_ptr2
py.test.raises(ArenaError, arena_reserve, a + ssize + 1, # misaligned
llmemory.sizeof(S))
arena_reserve(a + ssize + 1, llmemory.sizeof(S), check_alignment=False)
s2_ptr1 = cast_adr_to_ptr(a + ssize + 1, SPTR)
py.test.raises(lltype.UninitializedMemoryAccess, 's2_ptr1.x')
s2_ptr1.x = 2
s2_ptr2 = cast_adr_to_ptr(a + ssize + 1, SPTR)
assert s2_ptr2.x == 2
assert s2_ptr1 == s2_ptr2
assert s1_ptr1 != s2_ptr1
assert not (s2_ptr2 == s1_ptr2)
assert s1_ptr1 == cast_adr_to_ptr(a, SPTR)
S2 = lltype.Struct('S2', ('y',lltype.Char))
S2PTR = lltype.Ptr(S2)
py.test.raises(lltype.InvalidCast, cast_adr_to_ptr, a, S2PTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a+1, SPTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a+ssize, SPTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a+2*ssize, SPTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a+2*ssize+1, SPTR)
py.test.raises(ArenaError, arena_reserve, a+1, llmemory.sizeof(S),
False)
py.test.raises(ArenaError, arena_reserve, a+ssize, llmemory.sizeof(S),
False)
py.test.raises(ArenaError, arena_reserve, a+2*ssize, llmemory.sizeof(S),
False)
py.test.raises(ArenaError, arena_reserve, a+2*ssize+1, llmemory.sizeof(S),
False)
arena_reset(a, myarenasize, True)
py.test.raises(ArenaError, cast_adr_to_ptr, a, SPTR)
arena_reserve(a, llmemory.sizeof(S))
s1_ptr1 = cast_adr_to_ptr(a, SPTR)
assert s1_ptr1.x == 0
s1_ptr1.x = 5
arena_reserve(a + ssize, llmemory.sizeof(S2), check_alignment=False)
s2_ptr1 = cast_adr_to_ptr(a + ssize, S2PTR)
assert s2_ptr1.y == '\x00'
s2_ptr1.y = 'X'
assert cast_adr_to_ptr(a + 0, SPTR).x == 5
assert cast_adr_to_ptr((a + ssize + 1) - 1, S2PTR).y == 'X'
assert (a + 4) - (a + 1) == 3
def walk_page(self, page, block_size, ok_to_free_func):
"""Walk over all objects in a page, and ask ok_to_free_func()."""
#
# 'freeblock' is the next free block
freeblock = page.freeblock
#
# 'prevfreeblockat' is the address of where 'freeblock' was read from.
prevfreeblockat = lltype.direct_fieldptr(page, 'freeblock')
prevfreeblockat = llmemory.cast_ptr_to_adr(prevfreeblockat)
#
obj = llarena.getfakearenaaddress(llmemory.cast_ptr_to_adr(page))
obj += self.hdrsize
surviving = 0 # initially
skip_free_blocks = page.nfree
#
while True:
#
if obj == freeblock:
#
if skip_free_blocks == 0:
#
# 'obj' points to the first uninitialized block,
# or to the end of the page if there are none.
break
#
# 'obj' points to a free block. It means that
# 'prevfreeblockat.address[0]' does not need to be updated.
# Just read the next free block from 'obj.address[0]'.
skip_free_blocks -= 1
prevfreeblockat = obj
freeblock = obj.address[0]
#
else:
# 'obj' points to a valid object.
ll_assert(freeblock > obj,
"freeblocks are linked out of order")
#
if ok_to_free_func(obj):
#
# The object should die.
llarena.arena_reset(obj, _dummy_size(block_size), 0)
llarena.arena_reserve(obj,
llmemory.sizeof(llmemory.Address))
# Insert 'obj' in the linked list of free blocks.
prevfreeblockat.address[0] = obj
prevfreeblockat = obj
obj.address[0] = freeblock
#
# Update the number of free objects in the page.
page.nfree += 1
#
else:
# The object survives.
surviving += 1
#
obj += block_size
#
# Update the global total size of objects.
self.total_memory_used += r_uint(surviving * block_size)
#
# Return the number of surviving objects.
return surviving
def reserve(i):
b = a + i * llmemory.raw_malloc_usage(precomputed_size)
arena_reserve(b, precomputed_size)
return b
def test_arena():
S = lltype.Struct('S', ('x', lltype.Signed))
SPTR = lltype.Ptr(S)
ssize = llmemory.raw_malloc_usage(llmemory.sizeof(S))
myarenasize = 2 * ssize + 1
a = arena_malloc(myarenasize, False)
assert a != llmemory.NULL
assert a + 3 != llmemory.NULL
arena_reserve(a, llmemory.sizeof(S))
s1_ptr1 = cast_adr_to_ptr(a, SPTR)
s1_ptr1.x = 1
s1_ptr2 = cast_adr_to_ptr(a, SPTR)
assert s1_ptr2.x == 1
assert s1_ptr1 == s1_ptr2
py.test.raises(
ArenaError,
arena_reserve,
a + ssize + 1, # misaligned
llmemory.sizeof(S))
arena_reserve(a + ssize + 1, llmemory.sizeof(S), check_alignment=False)
s2_ptr1 = cast_adr_to_ptr(a + ssize + 1, SPTR)
py.test.raises(lltype.UninitializedMemoryAccess, 's2_ptr1.x')
s2_ptr1.x = 2
s2_ptr2 = cast_adr_to_ptr(a + ssize + 1, SPTR)
assert s2_ptr2.x == 2
assert s2_ptr1 == s2_ptr2
assert s1_ptr1 != s2_ptr1
assert not (s2_ptr2 == s1_ptr2)
assert s1_ptr1 == cast_adr_to_ptr(a, SPTR)
S2 = lltype.Struct('S2', ('y', lltype.Char))
S2PTR = lltype.Ptr(S2)
py.test.raises(lltype.InvalidCast, cast_adr_to_ptr, a, S2PTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a + 1, SPTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a + ssize, SPTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a + 2 * ssize, SPTR)
py.test.raises(ArenaError, cast_adr_to_ptr, a + 2 * ssize + 1, SPTR)
py.test.raises(ArenaError, arena_reserve, a + 1, llmemory.sizeof(S), False)
py.test.raises(ArenaError, arena_reserve, a + ssize, llmemory.sizeof(S),
False)
py.test.raises(ArenaError, arena_reserve, a + 2 * ssize,
llmemory.sizeof(S), False)
py.test.raises(ArenaError, arena_reserve, a + 2 * ssize + 1,
llmemory.sizeof(S), False)
arena_reset(a, myarenasize, True)
py.test.raises(ArenaError, cast_adr_to_ptr, a, SPTR)
arena_reserve(a, llmemory.sizeof(S))
s1_ptr1 = cast_adr_to_ptr(a, SPTR)
assert s1_ptr1.x == 0
s1_ptr1.x = 5
arena_reserve(a + ssize, llmemory.sizeof(S2), check_alignment=False)
s2_ptr1 = cast_adr_to_ptr(a + ssize, S2PTR)
assert s2_ptr1.y == '\x00'
s2_ptr1.y = 'X'
assert cast_adr_to_ptr(a + 0, SPTR).x == 5
assert cast_adr_to_ptr((a + ssize + 1) - 1, S2PTR).y == 'X'
assert (a + 4) - (a + 1) == 3
def test_arena_new_view():
a = arena_malloc(50, False)
arena_reserve(a, precomputed_size)
# we can now allocate the same space in new view
b = arena_new_view(a)
arena_reserve(b, precomputed_size)
def walk_page(self, page, block_size, ok_to_free_func):
"""Walk over all objects in a page, and ask ok_to_free_func()."""
#
# 'freeblock' is the next free block
freeblock = page.freeblock
#
# 'prevfreeblockat' is the address of where 'freeblock' was read from.
prevfreeblockat = lltype.direct_fieldptr(page, 'freeblock')
prevfreeblockat = llmemory.cast_ptr_to_adr(prevfreeblockat)
#
obj = llarena.getfakearenaaddress(llmemory.cast_ptr_to_adr(page))
obj += self.hdrsize
surviving = 0 # initially
skip_free_blocks = page.nfree
#
while True:
#
if obj == freeblock:
#
if skip_free_blocks == 0:
#
# 'obj' points to the first uninitialized block,
# or to the end of the page if there are none.
break
#
# 'obj' points to a free block. It means that
# 'prevfreeblockat.address[0]' does not need to be updated.
# Just read the next free block from 'obj.address[0]'.
skip_free_blocks -= 1
prevfreeblockat = obj
freeblock = obj.address[0]
#
else:
# 'obj' points to a valid object.
ll_assert(freeblock > obj,
"freeblocks are linked out of order")
#
if ok_to_free_func(obj):
#
# The object should die.
llarena.arena_reset(obj, _dummy_size(block_size), 0)
llarena.arena_reserve(obj,
llmemory.sizeof(llmemory.Address))
# Insert 'obj' in the linked list of free blocks.
prevfreeblockat.address[0] = obj
prevfreeblockat = obj
obj.address[0] = freeblock
#
# Update the number of free objects in the page.
page.nfree += 1
#
else:
# The object survives.
surviving += 1
#
obj += block_size
#
# Update the global total size of objects.
self.total_memory_used += r_uint(surviving * block_size)
#
# Return the number of surviving objects.
return surviving
def reserve(i):
b = a + i * llmemory.raw_malloc_usage(precomputed_size)
arena_reserve(b, precomputed_size)
return b
def arena_collection_for_test(pagesize, pagelayout, fill_with_objects=False):
assert " " not in pagelayout.rstrip(" ")
nb_pages = len(pagelayout)
arenasize = pagesize * (nb_pages + 1) - 1
ac = ArenaCollection(arenasize, pagesize, 9 * WORD)
#
def link(pageaddr, size_class, size_block, nblocks, nusedblocks, step=1):
assert step in (1, 2)
llarena.arena_reserve(pageaddr, llmemory.sizeof(PAGE_HEADER))
page = llmemory.cast_adr_to_ptr(pageaddr, PAGE_PTR)
if step == 1:
page.nfree = 0
nuninitialized = nblocks - nusedblocks
else:
page.nfree = nusedblocks
nuninitialized = nblocks - 2 * nusedblocks
page.freeblock = pageaddr + hdrsize + nusedblocks * size_block
if nusedblocks < nblocks:
chainedlists = ac.page_for_size
else:
chainedlists = ac.full_page_for_size
page.nextpage = chainedlists[size_class]
page.arena = ac.current_arena
chainedlists[size_class] = page
if fill_with_objects:
for i in range(0, nusedblocks * step, step):
objaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(objaddr, _dummy_size(size_block))
if step == 2:
prev = 'page.freeblock'
for i in range(1, nusedblocks * step, step):
holeaddr = pageaddr + hdrsize + i * size_block
llarena.arena_reserve(holeaddr,
llmemory.sizeof(llmemory.Address))
exec('%s = holeaddr' % prev, globals(), locals())
prevhole = holeaddr
prev = 'prevhole.address[0]'
endaddr = pageaddr + hdrsize + 2 * nusedblocks * size_block
exec('%s = endaddr' % prev, globals(), locals())
assert ac._nuninitialized(page, size_class) == nuninitialized
#
ac.allocate_new_arena()
num_initialized_pages = len(pagelayout.rstrip(" "))
ac._startpageaddr = ac.current_arena.freepages
if pagelayout.endswith(" "):
ac.current_arena.freepages += pagesize * num_initialized_pages
else:
ac.current_arena.freepages = NULL
ac.num_uninitialized_pages -= num_initialized_pages
#
for i in reversed(range(num_initialized_pages)):
pageaddr = pagenum(ac, i)
c = pagelayout[i]
if '1' <= c <= '9': # a partially used page (1 block free)
size_class = int(c)
size_block = WORD * size_class
nblocks = (pagesize - hdrsize) // size_block
link(pageaddr, size_class, size_block, nblocks, nblocks - 1)
elif c == '.': # a free, but initialized, page
llarena.arena_reserve(pageaddr, llmemory.sizeof(llmemory.Address))
pageaddr.address[0] = ac.current_arena.freepages
ac.current_arena.freepages = pageaddr
ac.current_arena.nfreepages += 1
elif c == '#': # a random full page, in the list 'full_pages'
size_class = fill_with_objects or 1
size_block = WORD * size_class
nblocks = (pagesize - hdrsize) // size_block
link(pageaddr, size_class, size_block, nblocks, nblocks)
elif c == '/': # a page 1/3 allocated, 1/3 freed, 1/3 uninit objs
size_class = fill_with_objects or 1
size_block = WORD * size_class
nblocks = (pagesize - hdrsize) // size_block
link(pageaddr,
size_class,
size_block,
nblocks,
nblocks // 3,
step=2)
#
ac.allocate_new_arena = lambda: should_not_allocate_new_arenas
return ac