On Wed, 05 Jun 2019, Greg Kroah-Hartman wrote: > On Wed, Jun 05, 2019 at 07:48:39AM +0100, Lee Jones wrote: > > On Tue, 04 Jun 2019, Greg Kroah-Hartman wrote: > > > On Tue, Jun 04, 2019 at 11:39:21AM -0700, Guenter Roeck wrote: > > > > On Tue, Jun 4, 2019 at 11:35 AM Greg Kroah-Hartman > > > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > > > > > > On Tue, Jun 04, 2019 at 01:58:38PM -0300, Ezequiel Garcia wrote: > > > > > > Hey Greg, > > > > > > > > > > > > > > + dev_info(&pdev->dev, "Created misc device /dev/%s\n", > > > > > > > > + data->misc.name); > > > > > > > > > > > > > > No need to be noisy, if all goes well, your code should be quiet. > > > > > > > > > > > > > > > > > > > I sometimes wonder about this being noise or not, so I will slightly > > > > > > hijack this thread for this discussion. > > > > > > > > > > > > >From a kernel developer point-of-view, or even from a platform > > > > > > developer or user with a debugging hat point-of-view, having > > > > > > a "device created" or "device registered" message is often very useful. > > > > > > > > > > For you, yes. For someone with 30000 devices attached to their system, > > > > > it is not, and causes booting to take longer than it should be. > > > > Who has 30,000 devices attached to their systems? > > More than you might imagine. > > > I would argue that > > in these special corner-cases, they should knock the log-level *down* > > a notch. For the rest of us who run normal platforms, an extra second > > of boot time renders a more forthcoming/useful system than if each of > > our devices initialised silently. > > > > Personally I like to know what devices I have on my system, and the > > kernel log is the first place I look. As far as I'm concerned, for > > the most part, if it's not in the kernel log, I don't have it. > > Then you "do not have" lots of devices, as we have been removing these > messages for a number of years now :) > > > "Oh wow, I didn't know I had XXX functionality on this platform." > > > > In my real job, I am currently enabling some newly released AArch64 > > based laptops for booting with ACPI. I must have wasted a day whilst > > enabling some of the devices the system relies upon, just to find > > out that 90% of them were actually probing semi-fine (at least probe() > > was succeeding), just silently. *grumble* > > Yup, that's normal. If you want to see what devices are in the system, > look in /sys/devices/ as that is what it is for, not the kernel log. My guess is that less than 1% of Linux users use /sys/devices in this way. It's a very unfriendly interface. Besides, when enabling a new platform, access to sysfs comes too far down the line to be useful in the majority of cases. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog
