Re: [PATCH V2 09/11] cxl/test: Add generic mock events

From: Ira Weiny
Date: Thu Dec 01 2022 - 12:53:45 EST


On Thu, Dec 01, 2022 at 02:37:27PM +0000, Jonathan Cameron wrote:
> On Wed, 30 Nov 2022 16:27:17 -0800
> ira.weiny@xxxxxxxxx wrote:
>
> > From: Ira Weiny <ira.weiny@xxxxxxxxx>
> >
> > Facilitate testing basic Get/Clear Event functionality by creating
> > multiple logs and generic events with made up UUID's.
> >
> > Data is completely made up with data patterns which should be easy to
> > spot in trace output.
> >
> > A single sysfs entry resets the event data and triggers collecting the
> > events for testing.
> >
> > Events are returned one at a time which is within the specification even
> > though it does not exercise the full capabilities of what a device may
> > do.
> >
> > Test traces are easy to obtain with a small script such as this:
> >
> > #!/bin/bash -x
> >
> > devices=`find /sys/devices/platform -name cxl_mem*`
> >
> > # Turn on tracing
> > echo "" > /sys/kernel/tracing/trace
> > echo 1 > /sys/kernel/tracing/events/cxl/enable
> > echo 1 > /sys/kernel/tracing/tracing_on
> >
> > # Generate fake interrupt
> > for device in $devices; do
> > echo 1 > $device/event_trigger
> > done
> >
> > # Turn off tracing and report events
> > echo 0 > /sys/kernel/tracing/tracing_on
> > cat /sys/kernel/tracing/trace
> >
> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> >
>
> A minor comment on xarray cleanup inline
>
> Jonathan
>
>
> > +void cxl_mock_remove_event_logs(struct device *dev)
> > +{
> > + struct mock_event_store *mes;
> > +
> > + mes = xa_erase(&mock_dev_event_store, (unsigned long)dev);
>
> As below, I'd move this into a devm_add_action_or_reset() so
> that we don't need to deal with doing it manually.

yea

>
> > +}
> > +EXPORT_SYMBOL_GPL(cxl_mock_remove_event_logs);
>
> ...
>
> > static int cxl_mock_mem_probe(struct platform_device *pdev)
> > {
> > struct device *dev = &pdev->dev;
> > struct cxl_memdev *cxlmd;
> > struct cxl_dev_state *cxlds;
> > + u32 ev_status;
> > void *lsa;
> > int rc;
> >
> > @@ -281,11 +304,13 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
> > if (rc)
> > return rc;
> >
> > + ev_status = cxl_mock_add_event_logs(cxlds);
>
> On error later in this function these leak. Just use devm_add_action_or_reset()
> inside cxl_mock_add_event_logs() so we don't have to care about that.

I see it now. There is an entry in the xarray which is leaked.

>
> > +
> > cxlmd = devm_cxl_add_memdev(cxlds);
> > if (IS_ERR(cxlmd))
> > return PTR_ERR(cxlmd);
> >
> > - cxl_mem_get_event_records(cxlds);
> > + __cxl_mem_get_event_records(cxlds, ev_status);
> >
> > if (resource_size(&cxlds->pmem_res) && IS_ENABLED(CONFIG_CXL_PMEM))
> > rc = devm_cxl_add_nvdimm(dev, cxlmd);
> > @@ -293,6 +318,12 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
> > return 0;
> > }
> >
> > +static int cxl_mock_mem_remove(struct platform_device *pdev)
> > +{
> > + cxl_mock_remove_event_logs(&pdev->dev);
> Why not use devm_add_action_or_reset()?

Yea that is a better pattern.

Ira