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| author | Ben Gamari <bgamari.foss@gmail.com> | 2018-07-06 11:11:20 -0400 |
|---|---|---|
| committer | Ben Gamari <ben@smart-cactus.org> | 2018-07-06 14:08:37 -0400 |
| commit | 8736715857d08cc1f88d766c257b39c05df20639 (patch) | |
| tree | 88d687c08c55aa0bc4a684536d5e32554a5c02ef /configure.ac | |
| parent | f03f0d61bebe287e0df0254c175eb2f183d697aa (diff) | |
| download | haskell-8736715857d08cc1f88d766c257b39c05df20639.tar.gz | |
rts: Enable two-step allocator on FreeBSD
Previously we would prevent any operating system not providing the
MEM_NORESERVE flag
from using the two-step allocator. Afterall, Linux will reserve
swap-space for
a mapping unless this flag is given, which is most certainly not what
we want.
However, it seems that FreeBSD provides the reservation-only mapping
behavior
that we expect despite not providing the MEM_NORESERVE macro. In fact,
it
provided the macro until 2014, when it was removed on account of not
being
implemented in the kernel. However, empirical evidence suggests that
just plain
mmap does what we want.
Reviewers: erikd, simonmar
Subscribers: rwbarton, thomie, erikd, carter
GHC Trac Issues: #15348
Differential Revision: https://phabricator.haskell.org/D4939
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/configure.ac b/configure.ac index ac464b6d2f..1976530df9 100644 --- a/configure.ac +++ b/configure.ac @@ -1182,22 +1182,23 @@ if test "$ac_cv_sizeof_void_p" -eq 8 ; then if test "x$EnableLargeAddressSpace" = "xyes" ; then if test "$ghc_host_os" = "darwin" ; then use_large_address_space=yes - elif test "$ghc_host_os" = "openbsd" ; then - # as of OpenBSD 5.8 (2015), OpenBSD does not support mmap with MAP_NORESERVE. - # The flag MAP_NORESERVE is supported for source compatibility reasons, - # but is completely ignored by OS mmap + elif test "$ghc_host_os" = "openbsd" ; then + # as of OpenBSD 5.8 (2015), OpenBSD does not support mmap with MAP_NORESERVE. + # The flag MAP_NORESERVE is supported for source compatibility reasons, + # but is completely ignored by OS mmap use_large_address_space=no else - AC_CHECK_DECLS([MAP_NORESERVE, MADV_FREE, MADV_DONTNEED],[],[], + AC_CHECK_DECLS([MAP_NORESERVE, MAP_GUARD, MADV_FREE, MADV_DONTNEED],[],[], [ #include <unistd.h> #include <sys/types.h> #include <sys/mman.h> #include <fcntl.h> ]) - if test "$ac_cv_have_decl_MAP_NORESERVE" = "yes" && - test "$ac_cv_have_decl_MADV_FREE" = "yes" || - test "$ac_cv_have_decl_MADV_DONTNEED" = "yes" ; then + if ( test "$ac_cv_have_decl_MAP_NORESERVE" = "yes" || + test "$ac_cv_have_decl_MAP_GUARD" = "yes" ) && + ( test "$ac_cv_have_decl_MADV_FREE" = "yes" || + test "$ac_cv_have_decl_MADV_DONTNEED" = "yes" ) ; then use_large_address_space=yes fi fi |