FYI, we noticed the below changes on

commit 6098b45b32e6baeacc04790773ced9340601d511 ("aio: block exit_aio() until all context requests are completed")


testbox/testcase/testparams: vm-vp-2G/xfstests/4HDD-btrfs-generic-quick

2ff396be602f10b5  6098b45b32e6baeacc04790773  
----------------  --------------------------  
         %stddev     %change         %stddev
             \          |                \  
     26352 ±  9%     -13.6%      22774 ±  1%  vmstat.system.cs
     10342 ±  6%     -12.3%       9066 ±  0%  vmstat.system.in
        37 ±  4%     -12.1%         32 ±  3%  time.percent_of_cpu_this_job_got
      1197 ±  2%     -14.2%       1028 ±  0%  vmstat.io.bi
     18470 ±  2%     -10.1%      16609 ±  1%  vmstat.io.bo
       157 ±  3%     +13.7%        179 ±  0%  time.elapsed_time

vm-vp-2G: qemu-system-x86_64 -enable-kvm -cpu Penryn
Memory: 2G

                          xfstests.generic.239.seconds

  30 ++-----------O---------------------------------------------------------+
     |              O         O            O         O                      |
  25 ++                O                                                    |
     |  O O  O O            O    O O  O  O    O O  O                        |
     |                   O                                                  |
  20 O+                                                                     |
     |                                                                      |
  15 ++                                                                     |
     |                                                                      |
  10 ++                                                                     |
     |                                                                      |
     |                                                                      |
   5 ++                                                                     |
     |                                                                      |
   0 *+-*-*--*-*--*-*--*-*--*-*--*-*--*--*-*--*-*--*-*--*-*--*-*--*-*--*-*--*


	[*] bisect-good sample
	[O] bisect-bad  sample

To reproduce:

	apt-get install ruby ruby-oj
	git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
	cd lkp-tests
	bin/setup-local job.yaml # the job file attached in this email
	bin/run-local   job.yaml


Disclaimer:
Results have been estimated based on internal Intel analysis and are provided
for informational purposes only. Any difference in system hardware or software
design or configuration may affect actual performance.


Thanks,
Fengguang