Fix regressions

sdb/commands/echo.py

@@ -38,8 +38,7 @@ def _init_parser(cls, name: str) -> argparse.ArgumentParser:
         return parser
 
     def _call(self, objs: Iterable[drgn.Object]) -> Iterable[drgn.Object]:
-        for obj in objs:
-            yield obj
+        yield from objs
 
         for addr in self.args.addrs:
             try:

sdb/commands/linux/internal/slub_helpers.py

@@ -151,6 +151,9 @@ def util(cache: drgn.Object) -> int:
 
 def lookup_cache_by_address(obj: drgn.Object) -> Optional[drgn.Object]:
     try:
+        # The pylint error disabled below is a false positive
+        # triggered by some updates to drgn's function signatures.
+        # pylint: disable=no-value-for-parameter
         cache = find_containing_slab_cache(obj)
         if cache.value_() == 0x0:
             return None

sdb/commands/linux/process.py

@@ -58,6 +58,9 @@ def _init_parser(cls, name: str) -> argparse.ArgumentParser:
 
     def _call(self, objs: Iterable[drgn.Object]) -> Iterable[drgn.Object]:
         for pid in self.args.pid:
+            # The pylint error disabled below is a false positive
+            # triggered by some updates to drgn's function signatures.
+            # pylint: disable=no-value-for-parameter
             yield find_pid(sdb.get_prog(), pid)
 
 
@@ -90,4 +93,7 @@ def _init_parser(cls, name: str) -> argparse.ArgumentParser:
 
     def _call(self, objs: Iterable[drgn.Object]) -> Iterable[drgn.Object]:
         for pid in self.args.pid:
+            # The pylint error disabled below is a false positive
+            # triggered by some updates to drgn's function signatures.
+            # pylint: disable=no-value-for-parameter
             yield find_task(sdb.get_prog(), pid)

sdb/commands/linux/stacks.py

@@ -400,6 +400,9 @@ def pretty_print(self, objs: Iterable[drgn.Object]) -> None:
 
     def no_input(self) -> Iterable[drgn.Object]:
         self.validate_context()
+        # The pylint error disabled below is a false positive
+        # triggered by some updates to drgn's function signatures.
+        # pylint: disable=no-value-for-parameter
         yield from filter(self.match_stack, for_each_task(sdb.get_prog()))
 
 

sdb/commands/linux/threads.py

@@ -30,7 +30,10 @@
 
 def _cmdline(obj: drgn.Object) -> str:
     try:
-        s = " ".join(map(lambda s: s.decode("utf-8"), cmdline(obj)))
+        ret = cmdline(obj)
+        if ret is None:
+            return ""
+        s = " ".join(map(lambda s: s.decode("utf-8"), ret))
 
         #
         # The command line for a given thread can be obnoxiously long,
@@ -97,4 +100,7 @@ def pretty_print(self, objs: Iterable[drgn.Object]) -> None:
         table.print_()
 
     def no_input(self) -> Iterable[drgn.Object]:
+        # The pylint error disabled below is a false positive
+        # triggered by some updates to drgn's function signatures.
+        # pylint: disable=no-value-for-parameter
         yield from for_each_task(sdb.get_prog())

sdb/commands/tail.py

@@ -48,5 +48,4 @@ def _call(self, objs: Iterable[drgn.Object]) -> Iterable[drgn.Object]:
         queue: Deque[drgn.Object] = deque(maxlen=self.args.count)
         for obj in objs:
             queue.append(obj)
-        for obj in queue:
-            yield obj
+        yield from queue

sdb/commands/zfs/histograms.py

@@ -130,8 +130,7 @@ def print_histogram(hist: drgn.Object,
                 min_bucket = bucket
             if bucket > max_bucket and count > 0:
                 max_bucket = bucket
-            if count > max_count:
-                max_count = count
+            max_count = max(max_count, count)
 
         HISTOGRAM_WIDTH_MAX = 40
         max_count = max(max_count, HISTOGRAM_WIDTH_MAX)

tests/integration/data/regression_output/dump.202303131823/zfs/zio -r

@@ -1539,6 +1539,7 @@
           0xffff9ac552bea780   WRITE VDEV_IO_START    -                             -
            0xffff9ac5500d1da0  WRITE VDEV_IO_DONE     -                         -62ms
             0xffff9ac60f5d4f00 WRITE VDEV_IO_START    -                         -78ms
+          0xffff9ac552beac70   WRITE DONE             -                             -
           0xffff9ac552bed8e0   WRITE VDEV_IO_START    -                             -
            0xffff9ac5500d4520  WRITE VDEV_IO_DONE     -                         -63ms
             0xffff9ac60f5d4f00 WRITE VDEV_IO_START    -                         -78ms