RFR: 8237198+8237199+8237200: ZGC: Share heap multi-mapping code across platforms
per.liden at oracle.com
Thu Jan 16 13:31:34 UTC 2020
Thanks for reviewing, Stuart!
On 1/16/20 2:24 PM, Stuart Monteith wrote:
> Looks good to me, thanks.
> On Wed, 15 Jan 2020 at 12:57, Per Liden <per.liden at oracle.com> wrote:
>> Please review this cleanup of the ZPhysicalMemory/ZBackingFile layer,
>> which aims to de-duplicate some of the multi-mapping code. I've split
>> the change into three separate patches, the main patch followed by two
>> patches doing some renaming.
>> 1) The ZBackingFile code was designed to allow platforms to decide if
>> they want to use heap multi-mapping or some other (possibly HW
>> supported) scheme. As of today, all our supported platforms do heap
>> multi-mapping, so there's some degree of code duplication in
>> ZBackingFile for each platform. This patch moves common multi-mapping
>> code into ZPhysicalMemoryManager. If we in the future find that we want
>> to support a platform that doesn't do multi-mapping, then we can
>> introduce an abstraction for this again.
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8237198
>> Webrev: http://cr.openjdk.java.net/~pliden/8237198/webrev.0
>> 2) Rename ZBackingFile to ZPhysicalMemoryBacking, since "File" is
>> somewhat misleading on platforms other than Linux.
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8237199
>> Webrev: http://cr.openjdk.java.net/~pliden/8237199/webrev.0
>> 3) Rename ZBackingPath to ZMountPoint, as it's a better name in light of
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8237200
>> Webrev: http://cr.openjdk.java.net/~pliden/8237200/webrev.0
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