[3/3] s390x: Check HWCAP bits against compiler flags

Message ID a9688d1a65abfd24b92120d36e6ccaad51e64d32.1620304013.git.fweimer@redhat.com
State New
Headers show
Series
  • Checking HWCAP bits against compiler flags
Related show

Commit Message

H.J. Lu via Libc-alpha May 6, 2021, 12:30 p.m.
When compiled with GCC 11.1 and -march=z14 -O3 build flags, running
ld.so (or any dynamically linked program) prints:

Fatal glibc error: CPU lacks VXE support (z14 or later required)

Co-Authored-By: Stefan Liebler <stli@linux.ibm.com>
---
 sysdeps/s390/s390-64/dl-hwcap-check.h | 40 +++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 sysdeps/s390/s390-64/dl-hwcap-check.h

-- 
2.30.2

Comments

H.J. Lu via Libc-alpha May 12, 2021, 7:43 a.m. | #1
On 06/05/2021 14:30, Florian Weimer via Libc-alpha wrote:
> When compiled with GCC 11.1 and -march=z14 -O3 build flags, running

> ld.so (or any dynamically linked program) prints:

> 

> Fatal glibc error: CPU lacks VXE support (z14 or later required)

> 

> Co-Authored-By: Stefan Liebler <stli@linux.ibm.com>

> ---

>  sysdeps/s390/s390-64/dl-hwcap-check.h | 40 +++++++++++++++++++++++++++

>  1 file changed, 40 insertions(+)

>  create mode 100644 sysdeps/s390/s390-64/dl-hwcap-check.h

> 

> diff --git a/sysdeps/s390/s390-64/dl-hwcap-check.h b/sysdeps/s390/s390-64/dl-hwcap-check.h

> new file mode 100644

> index 0000000000..87e18be6bd

> --- /dev/null

> +++ b/sysdeps/s390/s390-64/dl-hwcap-check.h

> @@ -0,0 +1,40 @@

> +/* Check for hardware capabilities after HWCAP parsing.  S390 version.

> +   Copyright (C) 2021 Free Software Foundation, Inc.

> +   This file is part of the GNU C Library.

> +

> +   The GNU C Library is free software; you can redistribute it and/or

> +   modify it under the terms of the GNU Lesser General Public

> +   License as published by the Free Software Foundation; either

> +   version 2.1 of the License, or (at your option) any later version.

> +

> +   The GNU C Library 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

> +   Lesser General Public License for more details.

> +

> +   You should have received a copy of the GNU Lesser General Public

> +   License along with the GNU C Library; if not, see

> +   <https://www.gnu.org/licenses/>.  */

> +

> +#ifndef _DL_HWCAP_CHECK_H

> +#define _DL_HWCAP_CHECK_H

> +

> +#include <ldsodefs.h>

> +

> +static inline void

> +dl_hwcap_check (void)

> +{

> +#if defined __ARCH__

> +# if __ARCH__ >= 13

> +  if (!(GLRO(dl_hwcap) & HWCAP_S390_VXRS_EXT2))

> +    _dl_fatal_printf ("\

> +Fatal glibc error: CPU lacks VXRS_EXT2 support (z15 or later required)\n");

> +# elif __ARCH__ >= 12

> +  if (!(GLRO(dl_hwcap) & HWCAP_S390_VXE))

> +    _dl_fatal_printf ("\

> +Fatal glibc error: CPU lacks VXE support (z14 or later required)\n");

> +# endif

> +#endif /* __ARCH__ */

> +}

> +

> +#endif /* _DL_HWCAP_CHECK_H */

> 


Hi Florian,

while running some tests, I got the messages as expected:
on z13:
- "-march=z13" => no message
- "-march=z14" => "z14 or later required"
- "-march=z15" => "z15 or later required"

on z14:
- "-march=z13" => no message
- "-march=z14" => no message
- "-march=z15" => "z15 or later required"

on z15:
- "-march=z13" => no message
- "-march=z14" => no message
- "-march=z15" => no message

Reviewed-by: Stefan Liebler <stli@linux.ibm.com>


Thanks,
Stefan

Patch

diff --git a/sysdeps/s390/s390-64/dl-hwcap-check.h b/sysdeps/s390/s390-64/dl-hwcap-check.h
new file mode 100644
index 0000000000..87e18be6bd
--- /dev/null
+++ b/sysdeps/s390/s390-64/dl-hwcap-check.h
@@ -0,0 +1,40 @@ 
+/* Check for hardware capabilities after HWCAP parsing.  S390 version.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _DL_HWCAP_CHECK_H
+#define _DL_HWCAP_CHECK_H
+
+#include <ldsodefs.h>
+
+static inline void
+dl_hwcap_check (void)
+{
+#if defined __ARCH__
+# if __ARCH__ >= 13
+  if (!(GLRO(dl_hwcap) & HWCAP_S390_VXRS_EXT2))
+    _dl_fatal_printf ("\
+Fatal glibc error: CPU lacks VXRS_EXT2 support (z15 or later required)\n");
+# elif __ARCH__ >= 12
+  if (!(GLRO(dl_hwcap) & HWCAP_S390_VXE))
+    _dl_fatal_printf ("\
+Fatal glibc error: CPU lacks VXE support (z14 or later required)\n");
+# endif
+#endif /* __ARCH__ */
+}
+
+#endif /* _DL_HWCAP_CHECK_H */