* Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> [200918 15:59]: > On Fri, Sep 18, 2020 at 06:25:02PM +0300, Tomi Valkeinen wrote: > > Hi, > > > > Has anyone noticed that booting would have slowed down in 5.8 and in 5.9-rcs? I'm booting x15 with > > my custom config builder, which uses omap2plus_defconfig as a base. I see: > > > > v5.7 > > [ 0.597765] cpuidle: using governor menu > > [ 0.793198] No ATAGs? > > > > [ 9.654611] Run /sbin/init as init process > > > > 5.8 > > [ 0.616660] cpuidle: using governor menu > > [ 4.439856] No ATAGs? > > > > [ 15.484710] Run /sbin/init as init process > > > > v5.9-rc5 > > [ 0.706165] cpuidle: using governor menu > > [ 6.761812] No ATAGs? > > > > [ 19.522536] Run /sbin/init as init process > > > > > > So v5.7 boots quickly, and init starts around 9.6 secs. 5.8 is much slower, and 5.9-rc5 even slower. > > I've tracked this down to device_link_add_missing_supplier_links() > taking about 40+ms to run, for every device added to the system. Given > the large number of devices, this adds up to 10s on v5.9-rc5, when > called during the initial of_platform_populate(). > > It doesn't seem there's a single culprit here (although I may have > missed it), "just" lots of walks through the whole device tree that end > up taking way too much time. I'm not planning to investigate this > further at this point. Hmm so do you have some commit that causes this slowness? In general, we should now be looking each device at module_init time only when configured in the dts. I guess it's possible we still have some extra walking of the whole device tree left but this sounds like a more generic issue though and not related to the omap dts conversion. Regards, Tony
