On Wed, 18 Mar 2026 22:21:50 -0700 SeongJae Park <[email protected]> wrote:
> DAMON test-purpose sysfs interface control Python module, _damon_sysfs, > is not supporting the newly added pause file. Add the support of the > file, for future test and use of the feature. > > Signed-off-by: SeongJae Park <[email protected]> > --- > tools/testing/selftests/damon/_damon_sysfs.py | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/damon/_damon_sysfs.py > b/tools/testing/selftests/damon/_damon_sysfs.py > index 2b4df655d9fd0..120b96ecbd741 100644 > --- a/tools/testing/selftests/damon/_damon_sysfs.py > +++ b/tools/testing/selftests/damon/_damon_sysfs.py > @@ -604,10 +604,11 @@ class DamonCtx: > targets = None > schemes = None > kdamond = None > + pause = None > idx = None > > def __init__(self, ops='paddr', monitoring_attrs=DamonAttrs(), > targets=[], > - schemes=[]): > + schemes=[], pause=False): Sashiko comment (https://sashiko.dev/#/patchset/[email protected]) and my reply. : Since this line is being modified, could the use of mutable default : arguments for monitoring_attrs, targets, and schemes cause unintended : state sharing between instances? : : In Python, default arguments are evaluated exactly once at function : definition time. If multiple DamonCtx objects are instantiated without : explicitly providing these parameters, they will share the exact same : object instances in memory. : : When the constructor later executes self.monitoring_attrs.context = self, : it overwrites the context reference of the shared object to point to the : newest DamonCtx instance. If multiple contexts are staged concurrently : relying on the default arguments, earlier contexts might inadvertently : write their sysfs files into the directory of the last created context. : : Would it be better to use None for the defaults and instantiate new objects : inside the constructor? Good points. Orthogonal to this patch, though. Also, there is no such use case of this class to my best knowledge. I will consider such change later, though. Thanks, SJ [...]
