On Mon, Feb 04, 2019 at 03:37:20PM +0000, Sudeep Holla wrote: > On Thu, Jan 31, 2019 at 04:05:59PM +0000, Sudeep Holla wrote: > > On Thu, Jan 31, 2019 at 12:48:49AM +0100, Rafael J. Wysocki wrote: > > > On Friday, January 25, 2019 4:09:06 PM CET Sudeep Holla wrote: > > > > The sysfs for the cpu caches are managed by adding devices with cpu > > > > as the parent in cpu_device_create() when secondary cpu is brought > > > > onlin. Generally when the secondary CPUs are hotplugged back is as part > > > > of resume from suspend-to-ram, we call cpu_device_create() from the cpu > > > > hotplug state machine while the cpu device associated with that CPU is > > > > not yet ready to be resumed as the device_resume() call happens bit > > > > later. > > > > It's not really needed to set the flag is_prepared for cpu devices are > > > > they are mostly pseudo device and hotplug framework deals with state > > > > machine and not managed through the cpu device. > > > > > > > > This often results in annoying warning when resuming: > > > > Enabling non-boot CPUs ... > > > > CPU1: Booted secondary processor > > > > cache: parent cpu1 should not be sleeping > > > > CPU1 is up > > > > CPU2: Booted secondary processor > > > > cache: parent cpu2 should not be sleeping > > > > CPU2 is up > > > > .... and so on. > > > > > > > > Just fix the warning by updating the device state quite early. > > > > > > > > Cc: "Rafael J. Wysocki" <[email protected]> > > > > Reported-by: Jisheng Zhang <[email protected]> > > > > Reported-by: Steve Longerbeam <[email protected]> > > > > Reported-by: Eugeniu Rosca <[email protected]> > > > > Signed-off-by: Sudeep Holla <[email protected]> > > > > --- > > > > drivers/base/cpu.c | 20 +++++++++++++++++++- > > > > include/linux/cpuhotplug.h | 1 + > > > > 2 files changed, 20 insertions(+), 1 deletion(-) > > > > > > > > Hi Rafael, > > > > > > > > This is getting reported for quite some time. Let me know if you have > > > > better solution to fix this harmless yet annoying warnings during system > > > > resume. > > > > > > I'd rather have a flag in struct dev_pm_info that will cause the message > > > to > > > be suppressed if set. > > > > > > It could be used for other purposes too then in princple (like skipping > > > the > > > creation of empty "power" attr groups in sysfs for devices that don't > > > need them etc.). > > > > > Thanks for the suggestion. I did quick hack and came up with something > > below. I wanted to run through you once before I materialise it into > > a formal patch to check if I understood your suggestion correctly. > > We can move no_pm_required outside dev_pm_info struct and rename with > > any better names. > > > > Sorry for the nag, since the title has RFC, thought there are chances of > this getting lost. Let me know if the below idea aligns with your suggestion ?
Personally, I ignore RFC patches unless I'm accidentally interested in them, as it shows that the author doesn't feel good enough to propose them as a real solution :) But that's just me... thanks, greg k-h
