Created student weenix repository

1 files changed, 109 insertions, 0 deletions

diff --git a/python/weenix/kmem.py b/python/weenix/kmem.py
new file mode 100644
index 0000000..8f8a6f2
--- /dev/null
+++ b/python/weenix/kmem.py
@@ -0,0 +1,109 @@
+import gdb
+import weenix
+
+import weenix.list
+
+PAGE_SIZE = 4096
+
+_uint32_type = gdb.lookup_type("uint32_t")
+_uintptr_type = gdb.lookup_type("uintptr_t")
+_slab_type = gdb.lookup_type("struct slab")
+_allocator_type = gdb.lookup_type("struct slab_allocator")
+_bufctl_type = gdb.lookup_type("struct slab_bufctl")
+_void_type = gdb.lookup_type("void")
+
+# for Python 3 compatibility, where xrange is done away with
+try:
+    xrange
+except NameError:
+    xrange = range
+
+class Slab:
+
+	def __init__(self, alloc, val):
+		self._alloc = alloc
+		if (val.type.code == gdb.TYPE_CODE_PTR):
+			self._value = val.cast(_slab_type.pointer()).dereference()
+		else:
+			self._value = val.cast(_slab_type)
+
+	def objs(self, typ=None):
+		next = self._value["s_addr"]
+		for i in xrange(int(self._alloc["sa_slab_nobjs"])):
+			bufctl = (next.cast(_uintptr_type)
+					  + self._alloc["sa_objsize"]).cast(_bufctl_type.pointer())
+			if (bufctl.dereference()["u"]["sb_slab"] == self._value.address):
+				# if redzones are in effect we need to skip them
+				if (int(next.cast(_uint32_type.pointer()).dereference()) == 0xdeadbeef):
+					value = (next.cast(_uint32_type.pointer()) + 1).cast(_void_type.pointer())
+				else:
+					value = next
+
+				if (typ != None):
+					yield value.cast(typ.pointer())
+				else:
+					yield value
+					
+			next = (next.cast(_uintptr_type)
+					+ self._alloc["sa_objsize"]
+					+ _bufctl_type.sizeof).cast(_void_type.pointer())
+
+class SlabAllocator:
+
+	def __init__(self, val):
+		if (val.type.code == gdb.TYPE_CODE_PTR):
+			self._value = val.cast(_allocator_type.pointer()).dereference()
+		else:
+			self._value = val.cast(_allocator_type)
+
+	def name(self):
+		return self._value["sa_name"].string()
+
+	def size(self):
+		return int(self._value["sa_objsize"])
+
+	def slabs(self):
+		next = self._value["sa_slabs"]
+		while (next != 0):
+			yield Slab(self._value, next.dereference())
+			next = next.dereference()["s_next"]
+
+	def objs(self, typ=None):
+		for slab in self.slabs():
+			for obj in slab.objs(typ):
+				yield obj
+
+	def __str__(self):
+		res =  "name:      {0}\n".format(self.name())
+		res += "slabcount: {0}\n".format(len(list(self.slabs())))
+		res += "objsize:   {0}\n".format(self.size())
+		res += "objcount:  {0}".format(len(list(self.objs())))
+		return res
+
+def allocators():
+	next = gdb.parse_and_eval("slab_allocators")
+	while (next != 0):
+		yield SlabAllocator(next.dereference())
+		next = next.dereference()["sa_next"]
+
+def allocator(name):
+	for alloc in allocators():
+		if name == alloc.name():
+			return alloc
+	raise KeyError(name)
+
+def pagesize():
+	return PAGE_SIZE
+
+def freepages():
+	freepages = dict()
+	for pagegroup in weenix.list.load("pagegroup_list", "struct pagegroup", "pg_link"):
+		freelist = pagegroup.item()["pg_freelist"]
+		for order in xrange(freelist.type.sizeof // freelist.type.target().sizeof):
+			psize = (1 << order) * PAGE_SIZE
+			count = len(weenix.list.load(freelist[order]))
+			if (order in freepages):
+				freepages[order] += count
+			else:
+				freepages[order] = count
+	return freepages