nptl: Eliminate <smp.h> 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  <adhemerval.zanella@linaro.org>

3 files changed, 20 insertions, 78 deletions

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 <https://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <string.h>
-#include <sys/utsname.h>
-#include <not-cancel.h>
-
-/* 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
+   <https://www.gnu.org/licenses/>.  */
+
+/* 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 <https://www.gnu.org/licenses/>.  */
-
-static inline int
-is_smp_system (void)
-{
-  return 0;
-}