Hi all, On Fri, 22 May 2020 17:17:08 +1000 Stephen Rothwell wrote: > > On Thu, 21 May 2020 18:35:22 +0100 Will Deacon wrote: > > > > [+Marco and Boris] > > > > On Fri, May 22, 2020 at 03:31:19AM +1000, Stephen Rothwell wrote: > > > After merging the tip tree, all my linux-next builds took signficantly > > > longer and used much more memory. In some cases, builds would seg fault > > > due to running out of memory :-( > > > > > > I have eventaully bisected it to commit > > > > > > cdd28ad2d811 ("READ_ONCE: Use data_race() to avoid KCSAN instrumentation") > > > > > > For my (e.g.) x86_64 allmodconfig builds (cross compiled on PowerPC le, > > > -j80) the elapsed time went from around 9 minutes to over 17 minutes > > > and the maximum resident size (as reported by /usr/bin/time) from around > > > 500M to around 2G (I saw lots of cc1 processes over 2G in size). > > > > > > For tomorrow's linux-next (well, later today :-() I will revert that > > > commit (and its child) when I merge the tip tree. > > > > Sorry about that, seems we can't avoid running into compiler problems with > > this lot. The good news is that there's a series to fix this here: > > > > https://lore.kernel.org/r/20200521142047.169334-1-elver@google.com > > > > so hopefully this be fixed in -tip soon (but I agree that reverting the > > thing in -next in the meantime makes sense). > > Unfortunately, the revert didn't work, so instead I have used the tip > tree from next-20200518 for today (hopefully this will all be sorted > out by Monday). And the rcu tree has merged part of the tip tree that contains the offending commits, so I have used the version fo the rcu tree from next-20200519 for today. -- Cheers, Stephen Rothwell