From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54958) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a7YuK-0005Fr-LK for qemu-devel@nongnu.org; Fri, 11 Dec 2015 20:23:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a7YuJ-00007o-E5 for qemu-devel@nongnu.org; Fri, 11 Dec 2015 20:23:32 -0500 References: <1449804437-30373-1-git-send-email-eblake@redhat.com> From: John Snow Message-ID: <566B770C.8070308@redhat.com> Date: Fri, 11 Dec 2015 20:23:24 -0500 MIME-Version: 1.0 In-Reply-To: <1449804437-30373-1-git-send-email-eblake@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Qemu-block] [PATCH for-2.5?] qemu-iotests: Reduce racy output in 028 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake , qemu-devel@nongnu.org Cc: Kevin Wolf , "open list:Block layer core" On 12/10/2015 10:27 PM, Eric Blake wrote: > On my machine, './check -qcow2 028' was failing about 80% of the > time, due to a race in how many times the repeated attempts > to run 'info block-jobs' could occur before the job was done, > showing up as a failure of fewer '(qemu) ' prompts than in the > expected output. Silence the output during the repetitions, then > add a final clean command to keep the expected output useful; > once patched, I was finally able to run the test 20 times in a > row with no failures. > Son of a gun: 028 4s ... - output mismatch (see 028.out.bad) --- /home/bos/jsnow/src/q3mu/tests/qemu-iotests/028.out 2015-10-09 13:33:06.823758271 -0400 +++ 028.out.bad 2015-12-11 20:12:23.688952510 -0500 @@ -470,7 +470,7 @@ Formatting 'TEST_DIR/t.IMGFMT.copy', fmt=IMGFMT size=4294968832 backing_file=TEST_DIR/t.IMGFMT.base backing_fmt=IMGFMT (qemu) -(qemu) info block-jobs +info block-jobs Type backup, device disk: Completed 0 of 4294968832 bytes, speed limit 0 bytes/s info block-jobs No active jobs Something must have changed to make it more prone to races, somehow. Venus... Swamp gas... > Signed-off-by: Eric Blake > --- > > Not sure if this is the best fix, or if it is even appropriate > for inclusion in 2.5 this late in the game. > > tests/qemu-iotests/028 | 6 ++++-- > tests/qemu-iotests/028.out | 3 --- > 2 files changed, 4 insertions(+), 5 deletions(-) > > diff --git a/tests/qemu-iotests/028 b/tests/qemu-iotests/028 > index a1f4423..756c335 100755 > --- a/tests/qemu-iotests/028 > +++ b/tests/qemu-iotests/028 > @@ -111,10 +111,12 @@ h=$QEMU_HANDLE > QEMU_COMM_TIMEOUT=1 > > # Silence output since it contains the disk image path and QEMU's readline > -# character echoing makes it very hard to filter the output > +# character echoing makes it very hard to filter the output. Plus, there > +# is no telling how many times the command will repeat before succeeding. > _send_qemu_cmd $h "drive_backup disk ${TEST_IMG}.copy" "(qemu)" >/dev/null > _send_qemu_cmd $h "" "Formatting" | _filter_img_create > -qemu_cmd_repeat=20 _send_qemu_cmd $h "info block-jobs" "No active jobs" > +qemu_cmd_repeat=20 _send_qemu_cmd $h "info block-jobs" "No active jobs" >/dev/null > +_send_qemu_cmd $h "info block-jobs" "No active jobs" > _send_qemu_cmd $h 'quit' "" > > # Base image sectors > diff --git a/tests/qemu-iotests/028.out b/tests/qemu-iotests/028.out > index 29c9972..e03452d 100644 > --- a/tests/qemu-iotests/028.out > +++ b/tests/qemu-iotests/028.out > @@ -469,10 +469,7 @@ No errors were found on the image. > block-backup > > Formatting 'TEST_DIR/t.IMGFMT.copy', fmt=IMGFMT size=4294968832 backing_file=TEST_DIR/t.IMGFMT.base backing_fmt=IMGFMT > -(qemu) > (qemu) iininfinfoinfo info binfo blinfo bloinfo blocinfo blockinfo block-info block-jinfo block-joinfo block-jobinfo block-jobs > -Type backup, device disk: Completed 0 of 4294968832 bytes, speed limit 0 bytes/s > -iininfinfoinfo info binfo blinfo bloinfo blocinfo blockinfo block-info block-jinfo block-joinfo block-jobinfo block-jobs > No active jobs > === IO: pattern 195 > read 512/512 bytes at offset 3221194240 >