On Thu, 2017-09-28 at 12:31 +0100, Szabolcs Nagy wrote:
>
> i think this should be improved, see below.
Those were all good suggestions, here is a new patch that incorporates
the changes. I fixed the IFUNC_OPTIONS argument,
renamed ARCH_AARCH64_LINUX_LSE, got rid of the auxv references, and
changed HWCAP_TYPE to IFUNC_RESOLVER_ARGS.
Here is the new patch, tested with no regressions.
Steve Ellcey
sell...@cavium.com
2017-09-29 Steve Ellcey <sell...@cavium.com>
* Makefile.am (ARCH_AARCH64_LINUX): Add IFUNC_OPTIONS and
libatomic_la_LIBADD.
* config/linux/aarch64/host-config.h: New file.
* configure.ac (IFUNC_RESOLVER_ARGS): Define.
(ARCH_AARCH64_LINUX): New conditional for IFUNC builds.
* configure.tgt (aarch64): Set ARCH and try_ifunc.
(aarch64*-*-linux*) Update config_path.
(aarch64*-*-linux*) Set IFUNC_RESOLVER_ARGS.
* libatomic_i.h (GEN_SELECTOR): Add IFUNC_RESOLVER_ARGS argument.
* Makefile.in: Regenerate.
* auto-config.h.in: Regenerate.
* configure: Regenerate.
diff --git a/libatomic/Makefile.am b/libatomic/Makefile.am
index d731406..92d19c6 100644
--- a/libatomic/Makefile.am
+++ b/libatomic/Makefile.am
@@ -122,6 +122,10 @@ libatomic_la_LIBADD = $(foreach s,$(SIZES),$(addsuffix _$(s)_.lo,$(SIZEOBJS)))
## On a target-specific basis, include alternates to be selected by IFUNC.
if HAVE_IFUNC
+if ARCH_AARCH64_LINUX
+IFUNC_OPTIONS = -march=armv8.1-a
+libatomic_la_LIBADD += $(foreach s,$(SIZES),$(addsuffix _$(s)_1_.lo,$(SIZEOBJS)))
+endif
if ARCH_ARM_LINUX
IFUNC_OPTIONS = -march=armv7-a -DHAVE_KERNEL64
libatomic_la_LIBADD += $(foreach s,$(SIZES),$(addsuffix _$(s)_1_.lo,$(SIZEOBJS)))
diff --git a/libatomic/config/linux/aarch64/host-config.h b/libatomic/config/linux/aarch64/host-config.h
index e69de29..08810a9 100644
--- a/libatomic/config/linux/aarch64/host-config.h
+++ b/libatomic/config/linux/aarch64/host-config.h
@@ -0,0 +1,36 @@
+/* Copyright (C) 2017 Free Software Foundation, Inc.
+
+ This file is part of the GNU Atomic Library (libatomic).
+
+ Libatomic is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ Libatomic is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ more details.
+
+ Under Section 7 of GPL version 3, you are granted additional
+ permissions described in the GCC Runtime Library Exception, version
+ 3.1, as published by the Free Software Foundation.
+
+ You should have received a copy of the GNU General Public License and
+ a copy of the GCC Runtime Library Exception along with this program;
+ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+ <http://www.gnu.org/licenses/>. */
+
+#if HAVE_IFUNC
+#include <stdlib.h>
+
+# ifdef HWCAP_ATOMICS
+# define IFUNC_COND_1 (hwcap & HWCAP_ATOMICS)
+# else
+# define IFUNC_COND_1 (false)
+# endif
+# define IFUNC_NCOND(N) (1)
+
+#endif /* HAVE_IFUNC */
+
+#include_next <host-config.h>
diff --git a/libatomic/configure.ac b/libatomic/configure.ac
index 023f172..b717d3d 100644
--- a/libatomic/configure.ac
+++ b/libatomic/configure.ac
@@ -163,6 +163,10 @@ if test -n "$UNSUPPORTED"; then
AC_MSG_ERROR([Configuration ${target} is unsupported.])
fi
+# Write out the ifunc resolver arg type.
+AC_DEFINE_UNQUOTED(IFUNC_RESOLVER_ARGS, $IFUNC_RESOLVER_ARGS,
+ [Define ifunc resolver function argument.])
+
# Disable fallbacks to __sync routines from libgcc. Otherwise we'll
# make silly decisions about what the cpu can do.
CFLAGS="$save_CFLAGS -fno-sync-libcalls $XCFLAGS"
@@ -247,6 +251,8 @@ AC_SUBST(LIBS)
AC_SUBST(SIZES)
AM_CONDITIONAL(HAVE_IFUNC, test x$libat_cv_have_ifunc = xyes)
+AM_CONDITIONAL(ARCH_AARCH64_LINUX,
+ [expr "$config_path" : ".* linux/aarch64 .*" > /dev/null])
AM_CONDITIONAL(ARCH_ARM_LINUX,
[expr "$config_path" : ".* linux/arm .*" > /dev/null])
AM_CONDITIONAL(ARCH_I386,
diff --git a/libatomic/configure.tgt b/libatomic/configure.tgt
index b8af3ab..388ae95 100644
--- a/libatomic/configure.tgt
+++ b/libatomic/configure.tgt
@@ -40,6 +40,14 @@ case "${target_cpu}" in
riscv*) ARCH=riscv ;;
sh*) ARCH=sh ;;
+ aarch64*)
+ ARCH=aarch64
+ case "${target}" in
+ aarch64*-*-linux*)
+ try_ifunc=yes
+ ;;
+ esac
+ ;;
arm*)
ARCH=arm
case "${target}" in
@@ -109,6 +117,11 @@ fi
# Other system configury
case "${target}" in
+ aarch64*-*-linux*)
+ # OS support for atomic primitives.
+ config_path="${config_path} linux/aarch64 posix"
+ ;;
+
arm*-*-linux*)
# OS support for atomic primitives.
config_path="${config_path} linux/arm posix"
@@ -153,3 +166,14 @@ case "${target}" in
UNSUPPORTED=1
;;
esac
+
+# glibc will pass hwcap to ifunc resolver functions as an argument.
+# The type may be different on different architectures.
+case "${target}" in
+ aarch64*-*-*)
+ IFUNC_RESOLVER_ARGS="uint64_t hwcap"
+ ;;
+ *)
+ IFUNC_RESOLVER_ARGS="void"
+ ;;
+esac
diff --git a/libatomic/libatomic_i.h b/libatomic/libatomic_i.h
index 4eb372a..b25f2f3 100644
--- a/libatomic/libatomic_i.h
+++ b/libatomic/libatomic_i.h
@@ -240,7 +240,7 @@ bool libat_is_lock_free (size_t, void *) MAN(is_lock_free);
# if IFUNC_NCOND(N) == 1
# define GEN_SELECTOR(X) \
extern typeof(C2(libat_,X)) C3(libat_,X,_i1) HIDDEN; \
- static void * C2(select_,X) (void) \
+ static void * C2(select_,X) (IFUNC_RESOLVER_ARGS) \
{ \
if (IFUNC_COND_1) \
return C3(libat_,X,_i1); \
@@ -250,7 +250,7 @@ bool libat_is_lock_free (size_t, void *) MAN(is_lock_free);
# define GEN_SELECTOR(X) \
extern typeof(C2(libat_,X)) C3(libat_,X,_i1) HIDDEN; \
extern typeof(C2(libat_,X)) C3(libat_,X,_i2) HIDDEN; \
- static void * C2(select_,X) (void) \
+ static void * C2(select_,X) (IFUNC_RESOLVER_ARGS) \
{ \
if (IFUNC_COND_1) \
return C3(libat_,X,_i1); \
@@ -263,7 +263,7 @@ bool libat_is_lock_free (size_t, void *) MAN(is_lock_free);
extern typeof(C2(libat_,X)) C3(libat_,X,_i1) HIDDEN; \
extern typeof(C2(libat_,X)) C3(libat_,X,_i2) HIDDEN; \
extern typeof(C2(libat_,X)) C3(libat_,X,_i3) HIDDEN; \
- static void * C2(select_,X) (void) \
+ static void * C2(select_,X) (IFUNC_RESOLVER_ARGS) \
{ \
if (IFUNC_COND_1) \
return C3(libat_,X,_i1); \
