[v2] x86: set spincount 1 for x86 hybrid platform
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Commit Message
From: "Zhang, Jun" <jun.zhang@intel.com>
By test, we find in hybrid platform spincount 1 is better.
Use '-march=native -Ofast -funroll-loops -flto',
results as follows:
spec2017 speed RPL ADL
657.xz_s 0.00% 0.50%
603.bwaves_s 10.90% 26.20%
607.cactuBSSN_s 5.50% 72.50%
619.lbm_s 2.40% 2.50%
621.wrf_s -7.70% 2.40%
627.cam4_s 0.50% 0.70%
628.pop2_s 48.20% 153.00%
638.imagick_s -0.10% 0.20%
644.nab_s 2.30% 1.40%
649.fotonik3d_s 8.00% 13.80%
654.roms_s 1.20% 1.10%
Geomean-int 0.00% 0.50%
Geomean-fp 6.30% 21.10%
Geomean-all 5.70% 19.10%
omp2012 RPL ADL
350.md -1.81% -1.75%
351.bwaves 7.72% 12.50%
352.nab 14.63% 19.71%
357.bt331 -0.20% 1.77%
358.botsalgn 0.00% 0.00%
359.botsspar 0.00% 0.65%
360.ilbdc 0.00% 0.25%
362.fma3d 2.66% -0.51%
363.swim 10.44% 0.00%
367.imagick 0.00% 0.12%
370.mgrid331 2.49% 25.56%
371.applu331 1.06% 4.22%
372.smithwa 0.74% 3.34%
376.kdtree 10.67% 16.03%
GEOMEAN 3.34% 5.53%
include/ChangeLog:
* spincount.h: New file.
libgomp/ChangeLog:
* env.c (initialize_env): Use do_adjust_default_spincount.
* config/linux/x86/spincount.h: New file.
---
include/spincount.h | 33 +++++++++++++++++++
libgomp/config/linux/x86/spincount.h | 49 ++++++++++++++++++++++++++++
libgomp/env.c | 6 +++-
3 files changed, 87 insertions(+), 1 deletion(-)
create mode 100644 include/spincount.h
create mode 100644 libgomp/config/linux/x86/spincount.h
Comments
On Wed, Oct 11, 2023 at 04:39:28PM +0800, Jun Zhang wrote:
> include/ChangeLog:
>
> * spincount.h: New file.
>
> libgomp/ChangeLog:
>
> * env.c (initialize_env): Use do_adjust_default_spincount.
> * config/linux/x86/spincount.h: New file.
Ok.
Jakub
new file mode 100644
@@ -0,0 +1,33 @@
+/* Copyright (C) 2023-2023 Free Software Foundation, Inc.
+ Contributed by Jun Zhang <jun.zhang@intel.com>.
+
+ This file is part of the GNU Offloading and Multi Processing Library
+ (libgomp).
+
+ Libgomp 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, or (at your option)
+ any later version.
+
+ Libgomp 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/>. */
+
+#ifndef GOMP_SPINCOUNT_H
+#define GOMP_SPINCOUNT_H 1
+
+static inline void do_adjust_default_spincount (void)
+{
+}
+
+#endif /* GOMP_SPINCOUNT_H */
new file mode 100644
@@ -0,0 +1,49 @@
+/* Copyright (C) 2023-2023 Free Software Foundation, Inc.
+ Contributed by Jun Zhang <jun.zhang@intel.com>.
+
+ This file is part of the GNU Offloading and Multi Processing Library
+ (libgomp).
+
+ Libgomp 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, or (at your option)
+ any later version.
+
+ Libgomp 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/>. */
+
+#ifndef GOMP_SPINCOUNT_H
+#define GOMP_SPINCOUNT_H 1
+
+#ifdef __x86_64__
+#include "cpuid.h"
+#include "libgomp.h"
+
+/* Only for x86 hybrid platform */
+static inline void do_adjust_default_spincount (void)
+{
+ unsigned int eax, ebx, ecx, edx;
+ if (__get_cpuid_count (7, 0, &eax, &ebx, &ecx, &edx)
+ /* CPUID.07H.0H:EDX[15] Hybrid. */
+ && ((edx >> 15) & 1))
+ gomp_spin_count_var = 1LL;
+}
+#else
+
+static inline void do_adjust_default_spincount (void)
+{
+}
+#endif
+
+#endif /* GOMP_SPINCOUNT_H */
@@ -61,6 +61,7 @@
#include "secure_getenv.h"
#include "environ.h"
+#include "spincount.h"
/* Default values of ICVs according to the OpenMP standard,
except for default-device-var. */
@@ -2431,7 +2432,10 @@ initialize_env (void)
if (wait_policy > 0)
gomp_spin_count_var = 30000000000LL;
else if (wait_policy < 0)
- gomp_spin_count_var = 300000LL;
+ {
+ gomp_spin_count_var = 300000LL;
+ do_adjust_default_spincount ();
+ }
}
/* gomp_throttled_spin_count_var is used when there are more libgomp
managed threads than available CPUs. Use very short spinning. */