tree 5a07f5969ccc5b761f6f00c3b928a9acb52a8a18
parent e7ca53bac2dbd281779b431b6ab29e9c39984256
author Jason Evans <jasone@canonware.com> 1479407091 -0800
committer Jason Evans <jasone@canonware.com> 1479407868 -0800

Refactor madvise(2) configuration.

Add feature tests for the MADV_FREE and MADV_DONTNEED flags to
madvise(2), so that MADV_FREE is detected and used for Linux kernel
versions 4.5 and newer.  Refactor pages_purge() so that on systems which
support both flags, MADV_FREE is preferred over MADV_DONTNEED.

This resolves #387.