On Fri, Sep 08, 2017 at 03:21:53PM -0600, Ross Zwisler wrote: > This adds a regression test for the following kernel patch: > > xfs: always use DAX if mount option is used > > This test will also pass with kernel v4.14-rc1 and beyond because the XFS > DAX I/O mount option has been disabled (but not removed), so the > "chattr -x" to turn off DAX doesn't actually do anything. > > Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> > Suggested-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> ..... > +pgsize=`$here/src/feature -s` > + > +# disable tracing, clear the existing trace buffer and turn on dax tracepoints > +echo 0 > /sys/kernel/debug/tracing/tracing_on > +echo > /sys/kernel/debug/tracing/trace > +echo 1 > /sys/kernel/debug/tracing/events/fs_dax/enable > + > +# enable tracing for our one mmap I/O, then see if dax was used > +echo 1 > /sys/kernel/debug/tracing/tracing_on > +xfs_io -t -c "truncate $pgsize" \ > + -c "chattr -x" \ > + -c "mmap -r 0 $pgsize" -c "mread 0 $pgsize" -c "munmap" \ > + -f $SCRATCH_MNT/testfile >> $seqres.full > +echo 0 > /sys/kernel/debug/tracing/tracing_on So what happens when the user is already tracing the test to find a bug and the test turns all their tracing off? Regardless of this screwing up developer bug triage, do we really want to add a dependency on kernel tracing into the test harness? Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
