"Maciej W. Rozycki" <macro@ds2.pg.gda.pl> writes:
> On 31 May 2001, Andreas Jaeger wrote:
>
>> Do it the following way:
>> - Define in sysdeps/unix/sysv/linux/kernel-features a new macro, e.g.
>> __ASSUME_TEST_AND_SET with the appropriate guards
>> - Do *both* implementations like this:
>> #include <kernel-features.h>
>> #if __ASSUME_TEST_AND_SET
>> fast code without fallback
>> #else
>> slow code that first tries kernel call and then falls back to sysmips
>> #endif
>> This way you get the fast one if you configure glibc with
>> --enable-kernel=2.4.6 if we assume that 2.4.6 is the first kernel with
>> those features.
>
> Thanks for the tip. It's reasonable, indeed. Now the point is to get
> Linux changes (once introduced) back to Linus' tree. It would be bad to
> to tie a kernel version with a feature that would be present in the CVS at
> oss.
>
>> Check other places in glibc for details how this can be done.
>
> OK, how about this patch then (the kernel version has to be set once
> known)?
>
> Maciej
diff -up --recursive --new-file glibc-2.2.3.macro/sysdeps/unix/sysv/linux/mips/_test_and_set.c glibc-2.2.3/sysdeps/unix/sysv/linux/mips/_test_and_set.c
--- glibc-2.2.3.macro/sysdeps/unix/sysv/linux/mips/_test_and_set.c Fri Jul 28 13:37:25 2000
+++ glibc-2.2.3/sysdeps/unix/sysv/linux/mips/_test_and_set.c Thu May 31 23:21:50 2001
@@ -21,6 +21,12 @@
defined in sys/tas.h */
#include <features.h>
+#include <sgidefs.h>
+#include <unistd.h>
+#include <sysdep.h>
+#include <sys/sysmips.h>
+
+#include "kernel-features.h"
#define _EXTERN_INLINE
#ifndef __USE_EXTERN_INLINES
@@ -28,3 +34,46 @@
#endif
#include "sys/tas.h"
+
+#ifdef __NR__test_and_set
+# ifdef __ASSUME__TEST_AND_SET
+# define __have_no__test_and_set 0
Don't add this, compare how we do it in similar cases.
diff -up --recursive --new-file glibc-2.2.3.macro/sysdeps/unix/sysv/linux/mips/sys/tas.h glibc-2.2.3/sysdeps/unix/sysv/linux/mips/sys/tas.h
--- glibc-2.2.3.macro/sysdeps/unix/sysv/linux/mips/sys/tas.h Sun Jan 7 04:35:41 2001
+++ glibc-2.2.3/sysdeps/unix/sysv/linux/mips/sys/tas.h Wed May 30 02:18:19 2001
@@ -22,11 +22,11 @@
#include <features.h>
#include <sgidefs.h>
-#include <sys/sysmips.h>
__BEGIN_DECLS
extern int _test_and_set (int *p, int v) __THROW;
+extern int ___test_and_set (int *p, int v) __THROW;
Why do you export this here?
Andreas
--
Andreas Jaeger
SuSE Labs aj@suse.de
private aj@arthur.inka.de
http://www.suse.de/~aj
