Re: [PATCH v3 46/57] perf: Simplify pmu_dev_alloc()
From: Peter Zijlstra <peterz@infradead.org>
Date: 2023-06-12 10:03:40
Also in:
dmaengine, linux-kbuild, linux-perf-users, lkml, llvm, rcu
On Mon, Jun 12, 2023 at 11:07:59AM +0200, Peter Zijlstra wrote:
quoted hunk ↗ jump to hunk
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> --- 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;
}