diff options
| -rw-r--r-- | configure.ac | 17 | ||||
| -rw-r--r-- | rts/posix/OSMem.c | 11 |
2 files changed, 17 insertions, 11 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 diff --git a/rts/posix/OSMem.c b/rts/posix/OSMem.c index e63e798be9..08f96350c9 100644 --- a/rts/posix/OSMem.c +++ b/rts/posix/OSMem.c @@ -102,8 +102,10 @@ void osMemInit(void) The naming is chosen from the Win32 API (VirtualAlloc) which does the same thing and has done so forever, while support for this in Unix systems has only been added recently and is hidden in the posix portability mess. - It is confusing because to get the reserve behavior we need MAP_NORESERVE - (which tells the kernel not to allocate backing space), but heh... + The Linux manpage suggests that mmap must be passed MAP_NORESERVE in order + to get reservation-only behavior. It is confusing because to get the reserve + behavior we need MAP_NORESERVE (which tells the kernel not to allocate backing + space), but heh... */ enum { @@ -161,7 +163,10 @@ my_mmap (void *addr, W_ size, int operation) else prot = PROT_NONE; if (operation == MEM_RESERVE) -# if defined(MAP_NORESERVE) +# if defined(MAP_GUARD) + // Provided by FreeBSD + flags = MAP_GUARD; +# elif defined(MAP_NORESERVE) flags = MAP_NORESERVE; # else # if defined(USE_LARGE_ADDRESS_SPACE) |