GDB: Improve tools to debug vm structures

sys/debug/__init__.py

@@ -10,6 +10,7 @@
 from .sync import CondVar, Mutex
 from .thread import Kthread, Thread, CurrentThread
 from .events import stop_handler
+from .virtmem import VmInfo
 
 
 def addPrettyPrinters():
@@ -32,6 +33,7 @@ def addPrettyPrinters():
 Kthread()
 Ktrace()
 Kgmon()
+VmInfo()
 
 # Functions
 CurrentThread()

sys/debug/cpu.py

@@ -1,7 +1,7 @@
 import gdb
 
 from .struct import GdbStructMeta
-from .utils import TextTable, cast
+from .utils import TextTable, cast, cast_ptr, get_arch
 from .cmd import UserCommand, CommandDispatcher
 
 
@@ -110,3 +110,54 @@ class Cpu(CommandDispatcher):
 
     def __init__(self):
         super().__init__('cpu', [TLB()])
+
+
+class PageTableMips():
+    def __init__(self, pmap):
+        self._pmap = pmap
+
+    def print(self):
+        pdp = cast_ptr(self._pmap['pde'], 'pde_t')
+        table = TextTable(types='ttttt', align='rrrrr')
+        table.header(['vpn', 'pte0', 'pte1', 'pte2', 'pte3'])
+        for i in range(1024):
+            pde = TLBLo(pdp[i])
+            if not pde.valid:
+                continue
+            ptp = cast_ptr(pde.ppn, 'pte_t')
+            pte = [TLBLo(ptp[j]) for j in range(1024)]
+            for j in range(0, 1024, 4):
+                if not any(pte.valid for pte in pte[j:j+4]):
+                    continue
+                pte4 = [str(pte) if pte.valid else '-' for pte in pte[j:j+4]]
+                table.add_row([f'{(i << 22) + (j << 12):8x}', pte4[0], pte4[1],
+                               pte4[2], pte4[3]])
+        print(table)
+
+
+class PageTableAArch64():
+    def __init__(self, pmap):
+        self._pmap = pmap
+        print("Page table not implemented for AArch64")
+
+    def print(self):
+        pass
+
+
+class PageTableRiscv():
+    def __init__(self, pmap):
+        self._pmap = pmap
+        print("Page table not implemented for RISC-V")
+
+    def print(self):
+        pass
+
+
+if get_arch() == 'mips':
+    PageTable = PageTableMips
+elif get_arch() == 'aarch64':
+    PageTable = PageTableAArch64
+elif get_arch() == 'riscv':
+    PageTable = PageTableRiscv
+else:
+    print(f'Arch {get_arch()} not supported')

sys/debug/kdump.py

@@ -1,4 +1,3 @@
-from .virtmem import VmPhysSeg, VmFreePages, VmMapSeg, PhysMap
 from .memory import Vmem, MallocStats, PoolStats
 from .cmd import CommandDispatcher
 
@@ -7,6 +6,7 @@ class Kdump(CommandDispatcher):
     """Examine kernel data structures."""
 
     def __init__(self):
-        super().__init__('kdump', [VmPhysSeg(), VmFreePages(), VmMapSeg(),
-                                   PhysMap(), Vmem(), MallocStats(),
-                                   PoolStats()])
+        super().__init__('kdump', [Vmem(),
+                                   MallocStats(),
+                                   PoolStats(),
+                                   ])

sys/debug/proc.py

@@ -1,9 +1,10 @@
 import gdb
 
-from .cmd import SimpleCommand, AutoCompleteMixin
+from .cmd import SimpleCommand
 from .utils import TextTable, global_var
 from .struct import GdbStructMeta, TailQueue, enum
 from .thread import Thread
+from .vm_map import VmMap
 from .sync import Mutex
 
 
@@ -12,6 +13,7 @@ class Process(metaclass=GdbStructMeta):
     __cast__ = {'p_pid': int,
                 'p_lock': Mutex,
                 'p_thread': Thread,
+                'p_uspace': VmMap,
                 'p_state': enum}
 
     @staticmethod
@@ -32,6 +34,12 @@ def list_all(cls):
         dead = TailQueue(global_var('zombie_list'), 'p_all')
         return map(cls, list(alive) + list(dead))
 
+    @classmethod
+    def find_by_pid(cls, pid):
+        for p in cls.list_all():
+            if p.p_pid == pid:
+                return p
+
     def __repr__(self):
         return 'proc{pid=%d}' % self.p_pid
 

sys/debug/utils.py

@@ -9,6 +9,10 @@ def cast(value, typename):
     return value.cast(gdb.lookup_type(typename))
 
 
+def cast_ptr(value, typename):
+    return value.cast(gdb.lookup_type(typename).pointer())
+
+
 def local_var(name):
     return gdb.newest_frame().read_var(name)
 
@@ -21,6 +25,14 @@ def relpath(path):
     return path.rsplit('sys/')[-1]
 
 
+def get_arch():
+    for arch in ['mips', 'aarch64', 'riscv']:
+        if arch in gdb.architecture_names():
+            return arch
+    print('Current architecture is not supported')
+    raise KeyError
+
+
 # calculates address of ret instruction within function body (MIPS specific)
 def func_ret_addr(name):
     s = gdb.execute('disass thread_create', to_string=True)