def alloc(self, sz = None):
if sz == None:
sz = self.page_sz
if sz > self.page_sz:
raise Exception("too big")
victim = self.get_free(sz)
if None is victim:
victim = self.get_page()
if victim[1] > sz:
self.free_list += [(victim[0] + sz, victim[1] - sz)]
self.allocations[victim[0]] = sz
c.memset(victim[0], 0, sz)
return victim[0]
def get_page(self):
if self._hugetlb_available:
assert self.page_sz == self._hugetlb_pgsz
prot = c.PROT_READ | c.PROT_WRITE
flags = c.MAP_ANONYMOUS | c.MAP_PRIVATE | c.MAP_LOCKED | c.MAP_HUGETLB | c.MAP_32BIT
flags |= (21 << c.MAP_HUGE_SHIFT)
sz = self._hugetlb_pgsz
page = c.mmap(0, sz, prot, flags, -1, 0)
if c.MAP_FAILED == page:
e = c.errno.value
raise Exception("mmap: 0x%x" % e)
else:
assert self.page_sz == self._page_sz
page = c.valloc(self._page_sz)
if 0 == page:
raise Exception("valloc")
if -1 == c.mlock(page, self._page_sz):
raise Exception("mlock")
c.memset(page, 0xFF, self.page_sz)
self.locked_pages += [page]
return (page, self.page_sz)
def get_page(self):
if self._hugetlb_available:
assert self.page_sz == self._hugetlb_pgsz
prot = c.PROT_READ | c.PROT_WRITE
flags = c.MAP_ANONYMOUS | c.MAP_PRIVATE | c.MAP_LOCKED | c.MAP_HUGETLB
flags |= (21 << c.MAP_HUGE_SHIFT)
sz = self._hugetlb_pgsz
page = c.mmap(0, sz, prot, flags, -1, 0)
if c.MAP_FAILED == page:
e = c.errno.value
raise Exception("mmap: 0x%x" % e)
else:
assert self.page_sz == self._page_sz
page = c.valloc(self._page_sz)
if 0 == page:
raise Exception("valloc")
if -1 == c.mlock(page, self._page_sz):
raise Exception("mlock")
c.memset(page, 0xFF, self.page_sz)
self.locked_pages += [page]
return (page, self.page_sz)
def free(self, v):
sz = self.allocations[v]
del self.allocations[v]
c.memset(v, 0xff, sz)
self.free_list += [(v, sz)]