From: Greg KH > Sent: 21 October 2020 17:13 > > On Fri, Sep 25, 2020 at 06:51:39AM +0200, Christoph Hellwig wrote: > > From: David Laight <David.Laight@xxxxxxxxxx> > > > > This lets the compiler inline it into import_iovec() generating > > much better code. > > > > Signed-off-by: David Laight <david.laight@xxxxxxxxxx> > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > > --- > > fs/read_write.c | 179 ------------------------------------------------ > > lib/iov_iter.c | 176 +++++++++++++++++++++++++++++++++++++++++++++++ > > 2 files changed, 176 insertions(+), 179 deletions(-) > > Strangely, this commit causes a regression in Linus's tree right now. > > I can't really figure out what the regression is, only that this commit > triggers a "large Android system binary" from working properly. There's > no kernel log messages anywhere, and I don't have any way to strace the > thing in the testing framework, so any hints that people can provide > would be most appreciated. My original commit just moved the function source from one file to another. So it is odd that it makes any difference. I don't even know if it gets inlined by Christoph's actual patch. (I have another patch that depended on it that I need to resubmit.) Some of the other changes from Christoph's same patch set might make a difference though. Might be worth forcing it to be not inlined - so it is no change. Or try adding a kernel log to import_iovec() or the associated copy failing. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
