Introduce qemu_madvise()
vl.c has a Sun-specific hack to supply a prototype for madvise(),
but the call site has apparently moved to arch_init.c.
Haiku doesn't implement madvise() in favor of posix_madvise().
OpenBSD and Solaris 10 don't implement posix_madvise() but madvise().
MinGW implements neither.
Check for madvise() and posix_madvise() in configure and supply qemu_madvise()
as wrapper. Prefer madvise() over posix_madvise() due to flag availability.
Convert all callers to use qemu_madvise() and QEMU_MADV_*.
Note that on Solaris the warning is fixed by moving the madvise() prototype,
not by qemu_madvise() itself. It helps with porting though, and it simplifies
most call sites.
v7 -> v8:
* Some versions of MinGW have no sys/mman.h header. Reported by Blue Swirl.
v6 -> v7:
* Adopt madvise() rather than posix_madvise() semantics for returning errors.
* Use EINVAL in place of ENOTSUP.
v5 -> v6:
* Replace two leftover instances of POSIX_MADV_NORMAL with QEMU_MADV_INVALID.
Spotted by Blue Swirl.
v4 -> v5:
* Introduce QEMU_MADV_INVALID, suggested by Alexander Graf.
Note that this relies on -1 not being a valid advice value.
v3 -> v4:
* Eliminate #ifdefs at qemu_advise() call sites. Requested by Blue Swirl.
This will currently break the check in kvm-all.c by calling madvise() with
a supported flag, which will not fail. Ideas/patches welcome.
v2 -> v3:
* Reuse the *_MADV_* defines for QEMU_MADV_*. Suggested by Alexander Graf.
* Add configure check for madvise(), too.
Add defines to Makefile, not QEMU_CFLAGS.
Convert all callers, untested. Suggested by Blue Swirl.
* Keep Solaris' madvise() prototype around. Pointed out by Alexander Graf.
* Display configure check results.
v1 -> v2:
* Don't rely on posix_madvise() availability, add qemu_madvise().
Suggested by Blue Swirl.
Signed-off-by: Andreas Färber <afaerber@opensolaris.org>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/configure b/configure
index 3bfc5e9..6a21bf2 100755
--- a/configure
+++ b/configure
@@ -2072,6 +2072,31 @@
fi
##########################################
+# check if we have madvise
+
+madvise=no
+cat > $TMPC << EOF
+#include <sys/types.h>
+#include <sys/mman.h>
+int main(void) { return madvise(NULL, 0, MADV_DONTNEED); }
+EOF
+if compile_prog "" "" ; then
+ madvise=yes
+fi
+
+##########################################
+# check if we have posix_madvise
+
+posix_madvise=no
+cat > $TMPC << EOF
+#include <sys/mman.h>
+int main(void) { return posix_madvise(NULL, 0, POSIX_MADV_DONTNEED); }
+EOF
+if compile_prog "" "" ; then
+ posix_madvise=yes
+fi
+
+##########################################
# check if trace backend exists
sh "$source_path/tracetool" "--$trace_backend" --check-backend > /dev/null 2> /dev/null
@@ -2238,6 +2263,8 @@
echo "fdt support $fdt"
echo "preadv support $preadv"
echo "fdatasync $fdatasync"
+echo "madvise $madvise"
+echo "posix_madvise $posix_madvise"
echo "uuid support $uuid"
echo "vhost-net support $vhost_net"
echo "Trace backend $trace_backend"
@@ -2478,6 +2505,12 @@
if test "$fdatasync" = "yes" ; then
echo "CONFIG_FDATASYNC=y" >> $config_host_mak
fi
+if test "$madvise" = "yes" ; then
+ echo "CONFIG_MADVISE=y" >> $config_host_mak
+fi
+if test "$posix_madvise" = "yes" ; then
+ echo "CONFIG_POSIX_MADVISE=y" >> $config_host_mak
+fi
# XXX: suppress that
if [ "$bsd" = "yes" ] ; then
