On Mon, Jun 12, 2023 at 11:07:59AM +0200, Peter Zijlstra wrote:
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
> kernel/events/core.c | 65 ++++++++++++++++++++++++---------------------------
> 1 file changed, 31 insertions(+), 34 deletions(-)
>
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -11285,49 +11285,46 @@ static void pmu_dev_release(struct devic
>
> static int pmu_dev_alloc(struct pmu *pmu)
> {
> + int ret;
>
> + struct device *dev __free(put_device) =
> + kzalloc(sizeof(struct device), GFP_KERNEL);
> + if (!dev)
> + return -ENOMEM;
>
> + dev->groups = pmu->attr_groups;
> + device_initialize(dev);
>
> + dev_set_drvdata(dev, pmu);
> + dev->bus = &pmu_bus;
> + dev->release = pmu_dev_release;
>
> + ret = dev_set_name(dev, "%s", pmu->name);
> if (ret)
> + return ret;
>
> + ret = device_add(dev);
> if (ret)
> + return ret;
>
> + struct device *del __free(device_del) = dev;
Greg, I'm not much familiar with the whole device model, but it seems
unfortunate to me that one has to call device_del() explicitly if we
already have a put_device() queued.
Is there a saner way to write this?
>
> + /* For PMUs with address filters, throw in an extra attribute: */
> + if (pmu->nr_addr_filters) {
> + ret = device_create_file(dev, &dev_attr_nr_addr_filters);
> + if (ret)
> + return ret;
> + }
> +
> + if (pmu->attr_update) {
> + ret = sysfs_update_groups(&dev->kobj, pmu->attr_update);
> + if (ret)
> + return ret;
> + }
> +
> + no_free_ptr(del);
> + pmu->dev = no_free_ptr(dev);
> + return 0;
> }
