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<p>It could be something simple like os::is_MP() returning false,
but then I would expect a lot more tests to fail.</p>
<p>dl<br>
</p>
<br>
<div class="moz-cite-prefix">On 9/30/16 1:14 PM, Bob Vandette wrote:<br>
</div>
<blockquote
cite="mid:1FE767B9-CD2B-4AA5-9F0E-346DEAEFE2D0@oracle.com"
type="cite">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
I realize that we don’t officially support G1GC for ARM but here’s
a crash running
<div class="">the test harness using G1GC on a 32-bit ARM server
VM in case anyone has</div>
<div class="">any insights.</div>
<div class=""><br class="">
</div>
<div class="">Bob.</div>
<div class=""><br class="">
</div>
<div><br class="">
<blockquote type="cite" class="">
<div class="">Begin forwarded message:</div>
<br class="Apple-interchange-newline">
<div style="margin-top: 0px; margin-right: 0px; margin-bottom:
0px; margin-left: 0px;" class=""><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b
class="">From: </b></span><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif;" class="">Bob Vandette <<a
moz-do-not-send="true"
href="mailto:bob.vandette@oracle.com" class="">bob.vandette@oracle.com</a>><br
class="">
</span></div>
<div style="margin-top: 0px; margin-right: 0px; margin-bottom:
0px; margin-left: 0px;" class=""><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b
class="">Subject: </b></span><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif;" class=""><b class="">Re: Webrev of Oracle ARM
& AARCH64 Sources</b><br class="">
</span></div>
<div style="margin-top: 0px; margin-right: 0px; margin-bottom:
0px; margin-left: 0px;" class=""><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b
class="">Date: </b></span><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif;" class="">September 30, 2016 at 9:58:55 AM EDT<br
class="">
</span></div>
<div style="margin-top: 0px; margin-right: 0px; margin-bottom:
0px; margin-left: 0px;" class=""><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b
class="">To: </b></span><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif;" class="">David Holmes <<a
moz-do-not-send="true"
href="mailto:David.Holmes@oracle.com" class="">David.Holmes@oracle.com</a>><br
class="">
</span></div>
<div style="margin-top: 0px; margin-right: 0px; margin-bottom:
0px; margin-left: 0px;" class=""><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif; color:rgba(0, 0, 0, 1.0);" class=""><b
class="">Cc: </b></span><span style="font-family:
-webkit-system-font, Helvetica Neue, Helvetica,
sans-serif;" class=""><a moz-do-not-send="true"
href="mailto:edward.nevill@gmail.com" class="">edward.nevill@gmail.com</a>,
<a moz-do-not-send="true"
href="mailto:aarch32-port-dev@openjdk.java.net" class="">aarch32-port-dev@openjdk.java.net</a>,
"<a moz-do-not-send="true"
href="mailto:hotspot-dev@openjdk.java.net" class="">hotspot-dev@openjdk.java.net</a>
developers" <<a moz-do-not-send="true"
href="mailto:hotspot-dev@openjdk.java.net" class="">hotspot-dev@openjdk.java.net</a>>,
<a moz-do-not-send="true"
href="mailto:aarch64-port-dev@openjdk.java.net" class="">aarch64-port-dev@openjdk.java.net</a><br
class="">
</span></div>
<br class="">
<div class="">
<div class=""><br class="">
<blockquote type="cite" class="">On Sep 30, 2016, at 7:23
AM, David Holmes <<a moz-do-not-send="true"
href="mailto:David.Holmes@oracle.com" class="">David.Holmes@oracle.com</a>>
wrote:<br class="">
<br class="">
Hi Ed,<br class="">
<br class="">
On 30/09/2016 8:32 PM, Edward Nevill wrote:<br class="">
<blockquote type="cite" class="">Hi Bob,<br class="">
<br class="">
On Wed, 2016-09-28 at 10:07 -0400, Bob Vandette wrote:<br
class="">
<blockquote type="cite" class="">I’m am please to
announce that I have completed our internal reviews
and can now<br class="">
open up the sources to our ARM 32 & 64 bit
implementations of JDK9.<br class="">
</blockquote>
<br class="">
Great news.<br class="">
<br class="">
<blockquote type="cite" class=""><br class="">
Here is a webrev that includes a patch that can be
applied on top of the<br class="">
(<a moz-do-not-send="true"
href="http://hg.openjdk.java.net/aarch32-port/jdk9-arm3264/"
class="">http://hg.openjdk.java.net/aarch32-port/jdk9-arm3264/</a>
) forest.<br class="">
<br class="">
<a moz-do-not-send="true"
href="http://cr.openjdk.java.net/%7Ebobv/arm3264/webrev"
class="">http://cr.openjdk.java.net/~bobv/arm3264/webrev</a>
<<a moz-do-not-send="true"
href="http://cr.openjdk.java.net/%7Ebobv/arm3264/webrev"
class="">http://cr.openjdk.java.net/~bobv/arm3264/webrev</a>><br
class="">
</blockquote>
<br class="">
I have built this natively on armv7 and aarch64
without problems. In both cases I built the
minimal,client,server combination.<br class="">
<br class="">
I have also tested the server build with JTreg hotspot
& langtools.<br class="">
<br class="">
On aarch64 I got the following results:-<br class="">
<br class="">
hotspot: Test results: passed: 1,280; failed: 8;
error: 43<br class="">
langtools: Test results: passed: 3,700; failed: 1;
error: 29<br class="">
<br class="">
This is fairly typical, for example, using the Linaro
1609 build I get<br class="">
<br class="">
hotspot: Test results: passed: 1,271; failed: 17;
error: 43<br class="">
langtools: Test results: passed: 3,715; failed: 3;
error: 12<br class="">
</blockquote>
<br class="">
So most of the "errors" are probably tests that are
ignored.<br class="">
<br class="">
<blockquote type="cite" class="">On armv7 I first of all
had to pin the jvm.cfg to use -server as it kept on
using the client as I was not running on a 'server
class machine' (since my armv7 device is a Samsung
Chromebook this is fair enough).<br class="">
<br class="">
However, I then had problems with the test harness
crashing with the error<br class="">
<br class="">
# Internal Error (synchronizer.cpp:1576), pid=6533,
tid=6542<br class="">
# guarantee(mid->header()->is_neutral())
failed: invariant<br class="">
<br class="">
(hs_err here <a moz-do-not-send="true"
href="http://cr.openjdk.java.net/%7Eenevill/aarch32/hs_err_pid6533.log"
class="">http://cr.openjdk.java.net/~enevill/aarch32/hs_err_pid6533.log</a>)<br
class="">
</blockquote>
<br class="">
Strange - that looks like our closed bug:<br class="">
<br class="">
<a moz-do-not-send="true"
href="https://bugs.openjdk.java.net/browse/JDK-8071540"
class="">https://bugs.openjdk.java.net/browse/JDK-8071540</a><br
class="">
<br class="">
which should be fixed. It was a missing memory barrier
issue.<br class="">
</blockquote>
<br class="">
I checked and this fix was applied but later a newer
implementation<br class="">
was added. The memory barriers were moved to
cas_for_lock_acquire<br class="">
with optimized versions for aarch64.<br class="">
<br class="">
Be aware that G1 support on 32-bit ARM is not fully
supported by the GC team.<br class="">
It’s experimental. This means that there was an attempt
to implement it but it<br class="">
has not undergone the same level of testing as other
platforms. I’ll forward this<br class="">
issue to the GC team.<br class="">
<br class="">
Bob.<br class="">
<br class="">
<br class="">
<blockquote type="cite" class=""><br class="">
Aside: we're going to have to figure out how to deal
with currently closed bug reports.<br class="">
<br class="">
David<br class="">
-----<br class="">
<br class="">
<blockquote type="cite" class="">On a subsequent run the
test harness locked up after 85 tests.<br class="">
<br class="">
It looks like there might be a problem with locks
breaking with G1GC. I will keep investigating.<br
class="">
<br class="">
I ran it again using the template interpreter for the
test harness and the server for the jdk under test and
it ran successfully.<br class="">
<br class="">
On armv7 I got<br class="">
<br class="">
hotspot: Test results: passed: 1,202; failed: 11;
error: 36<br class="">
langtools: Test results: passed: 3,718; failed: 5;
error: 8<br class="">
<br class="">
I also did some limited benchmarking which I am not
going to share on a public forum. Lets just say the
performance of the server JIT on armv7 was pleasing.<br
class="">
<br class="">
Thanks for all your work getting to this stage. It
looks good to push and you should shortly have
committeer rights, if you don't get them within a few
days ping me and I will give ops a nudge.<br class="">
<br class="">
All the best,<br class="">
Ed.<br class="">
<br class="">
<br class="">
</blockquote>
</blockquote>
<br class="">
</div>
</div>
</blockquote>
</div>
<br class="">
</blockquote>
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