From 26f7c72a99f4e46755ec2ff23a6a7cf9c2c337c3 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 13 Nov 2020 15:19:41 +0100 Subject: nptl: Eliminate and __is_smp Most systems are SMP, so optimizing for the UP case is no longer approriate. A dynamic check based on the kernel identification has been only implemented for i386 anyway. To disable adaptive mutexes on sh, define DEFAULT_ADAPTIVE_COUNT as zero for this architecture. Reviewed-by: Adhemerval Zanella --- sysdeps/unix/sysv/linux/i386/smp.h | 55 ------------------------ sysdeps/unix/sysv/linux/sh/adaptive_spin_count.h | 20 +++++++++ sysdeps/unix/sysv/linux/sh/smp.h | 23 ---------- 3 files changed, 20 insertions(+), 78 deletions(-) delete mode 100644 sysdeps/unix/sysv/linux/i386/smp.h create mode 100644 sysdeps/unix/sysv/linux/sh/adaptive_spin_count.h delete mode 100644 sysdeps/unix/sysv/linux/sh/smp.h (limited to 'sysdeps/unix/sysv/linux') diff --git a/sysdeps/unix/sysv/linux/i386/smp.h b/sysdeps/unix/sysv/linux/i386/smp.h deleted file mode 100644 index 85a630d048..0000000000 --- a/sysdeps/unix/sysv/linux/i386/smp.h +++ /dev/null @@ -1,55 +0,0 @@ -/* Determine whether the host has multiple processors. Linux version. - Copyright (C) 1996-2020 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 Library General Public License as - published by the Free Software Foundation; either version 2 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 - Library General Public License for more details. - - You should have received a copy of the GNU Library General Public - License along with the GNU C Library; see the file COPYING.LIB. If - not, see . */ - -#include -#include -#include -#include -#include - -/* Test whether the machine has more than one processor. This is not the - best test but good enough. More complicated tests would require `malloc' - which is not available at that time. */ -static inline int -is_smp_system (void) -{ - union - { - struct utsname uts; - char buf[512]; - } u; - char *cp; - - /* Try reading the number using `sysctl' first. */ - if (__uname (&u.uts) == 0) - cp = u.uts.version; - else - { - /* This was not successful. Now try reading the /proc filesystem. */ - int fd = __open64_nocancel ("/proc/sys/kernel/version", O_RDONLY); - if (__builtin_expect (fd, 0) == -1 - || __read_nocancel (fd, u.buf, sizeof (u.buf)) <= 0) - /* This also didn't work. We give up and say it's a UP machine. */ - u.buf[0] = '\0'; - - __close_nocancel_nostatus (fd); - cp = u.buf; - } - - return strstr (cp, "SMP") != NULL; -} diff --git a/sysdeps/unix/sysv/linux/sh/adaptive_spin_count.h b/sysdeps/unix/sysv/linux/sh/adaptive_spin_count.h new file mode 100644 index 0000000000..3431cd3d8c --- /dev/null +++ b/sysdeps/unix/sysv/linux/sh/adaptive_spin_count.h @@ -0,0 +1,20 @@ +/* Maximum adaptive spin count default for sh. + Copyright (C) 2020 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 + . */ + +/* Disable spinning because sh is always uniprocessor. */ +#define DEFAULT_ADAPTIVE_COUNT 0 diff --git a/sysdeps/unix/sysv/linux/sh/smp.h b/sysdeps/unix/sysv/linux/sh/smp.h deleted file mode 100644 index 55efedc0ba..0000000000 --- a/sysdeps/unix/sysv/linux/sh/smp.h +++ /dev/null @@ -1,23 +0,0 @@ -/* Determine whether the host has multiple processors. SH version. - Copyright (C) 2002-2020 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 Library General Public License as - published by the Free Software Foundation; either version 2 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 - Library General Public License for more details. - - You should have received a copy of the GNU Library General Public - License along with the GNU C Library; see the file COPYING.LIB. If - not, see . */ - -static inline int -is_smp_system (void) -{ - return 0; -} -- cgit v1.2.3-70-g09d2