On Thu, Jul 4, 2019 at 7:31 PM Rafael J. Wysocki <r...@rjwysocki.net> wrote: > > On Friday, June 28, 2019 5:10:40 PM CEST Greg KH wrote: > > On Thu, Jun 27, 2019 at 03:53:35PM -0700, Tri Vo wrote: > > > Userspace can use wakeup_sources debugfs node to plot history of suspend > > > blocking wakeup sources over device's boot cycle. This information can > > > then be used (1) for power-specific bug reporting and (2) towards > > > attributing battery consumption to specific processes over a period of > > > time. > > > > > > However, debugfs doesn't have stable ABI. For this reason, expose wakeup > > > sources statistics in sysfs under /sys/power/wakeup_sources/<name>/ > > > > > > Embedding a struct kobject into struct wakeup_source changes lifetime > > > requirements on the latter. To that end, change deallocation of struct > > > wakeup_source using kfree to kobject_put(). > > > > > > Change struct wakelock's wakeup_source member to a pointer to decouple > > > lifetimes of struct wakelock and struct wakeup_source for above reason. > > > > > > Introduce CONFIG_PM_SLEEP_STATS that enables/disables showing wakeup > > > source statistics in sysfs. > > > > > > Signed-off-by: Tri Vo <tr...@android.com> > > > > Ok, this looks much better, but I don't like the use of a "raw" kobject > > here. It is much simpler, and less code, to use 'struct device' > > instead. > > > > As proof, I reworked the patch to do just that, and it saves over 50 > > lines of .c code, which is always nice :) > > Thanks for taking the time to do that!
Thanks a lot, Greg! > > > Attached below is the reworked code, along with the updated > > documentation file. It creates devices in a virtual class, and you can > > easily iterate over them all by looking in /sys/class/wakeup/. > > That actually is nice - no need to add anything under /sys/power/. > > > Note, I'm note quite sure you need all of the changes you made in > > kernel/power/wakelock.c when you make the structure contain a pointer to > > the wakeup source and not the structure itself, but I just went with it > > and got it all to build properly. > > I'm not really sure about it either. > > > Also note, I've not actually tested this at all, only built it, so I > > _strongly_ suggest that you test this to make sure it really works :) > > > > What do you think? > > I agree with the direction. :-) I'll test things out and send v3 of the patch. Thanks!