@@ -50,7 +50,7 @@ def run_vm(self, record, shift, args, replay_path, image_path, port):
vm.add_args('-icount', 'shift=%s,rr=%s,rrfile=%s,rrsnapshot=init' %
(shift, mode, replay_path),
'-net', 'none')
- vm.add_args('-drive', 'file=%s,if=none' % image_path)
+ vm.add_args('-drive', 'file=%s,if=none,id=disk0' % image_path)
if args:
vm.add_args(*args)
vm.launch()
@@ -124,6 +124,14 @@ def gdb_bstep(g):
def vm_get_icount(vm):
return vm.qmp('query-replay')['return']['icount']
+ @staticmethod
+ def vm_snapshot(vm):
+ return vm.qmp('snapshot-save',
+ {'job-id': 'snapshot-job',
+ 'tag': 'manual',
+ 'vmstate': 'disk0',
+ 'devices': []})
+
def reverse_debugging(self, shift=7, args=None, x86_workaround=False):
logger = logging.getLogger('replay')
@@ -162,6 +170,9 @@ def reverse_debugging(self, shift=7, args=None, x86_workaround=False):
pc = self.get_pc(g)
logger.info('saving position %x' % pc)
steps.append(pc)
+ if i == self.STEPS//2:
+ logger.info('saving VM snapshot at step %x...' % i)
+ self.vm_snapshot(vm)
self.gdb_step(g)
if x86_workaround and i == 0 and self.vm_get_icount(vm) == 0:
logger.warn('failed to take first step, stepping again')
@@ -208,7 +219,9 @@ def reverse_debugging(self, shift=7, args=None, x86_workaround=False):
self.gdb_step(g)
logger.info('found position %x' % addr)
- # Try reverse stepping
+ # Try reverse stepping. The manual snapshot taken in the record
+ # phase should be used for reverse-stepping until the machine
+ # reverses to an icount older than the snapshot.
logger.info('stepping backward')
for addr in steps[::-1]:
self.gdb_bstep(g)
@@ -232,6 +245,8 @@ def reverse_debugging(self, shift=7, args=None, x86_workaround=False):
self.check_pc(g, last_pc)
logger.info('found position %x' % last_pc)
+ # This should load the last snapshot taken. Could that be verified
+ # with QMP?
logger.info('stepping backward')
self.gdb_bstep(g)
Make a manual snapshot halfway though initial building of the address map in record mode. This will cause the reverse-step and reverse-continue tests to load that snapshot when beginning from later points in the trace, exercising the post-initial snapshot saving and loading. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- tests/avocado/reverse_debugging.py | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-)