On Wed, 13 Jun 2001, H . J . Lu wrote:
> > What's the problem with the kernel? It works fine for my R3400A
> > DECstation. Glibc is 2.2.3 as released. If there is something wrong, I
> > definitely want to know.
>
> It has something to do with the atomic emulation in kernel for mips I.
Hmm, I thought Florian's sysmips() fixes went in. Here is a patch I use
successfully for some time. It doesn't work for small negative integers,
but glibc doesn't use them, AFAIK.
Another possibility is to use the set of two patches for
sys__test_and_set() I've sent here recently. This would break portability
for now, though, if you wanted to distribute glibc or kernel binaries.
This is also the reason I didn't put my current patched version of glibc
on my FTP site.
The patch is not against a current version of the kernel -- you might
need to apply it manually.
Maciej
--
+ Maciej W. Rozycki, Technical University of Gdansk, Poland +
+--------------------------------------------------------------+
+ e-mail: macro@ds2.pg.gda.pl, PGP key available +
patch-mips-2.4.0-test11-20001211-sysmips-0
diff -up --recursive --new-file linux-mips-2.4.0-test11-20001211.macro/arch/mips/kernel/sysmips.c linux-mips-2.4.0-test11-20001211/arch/mips/kernel/sysmips.c
--- linux-mips-2.4.0-test11-20001211.macro/arch/mips/kernel/sysmips.c Sat Nov 18 05:27:01 2000
+++ linux-mips-2.4.0-test11-20001211/arch/mips/kernel/sysmips.c Tue Dec 12 23:09:57 2000
@@ -75,21 +75,31 @@ sys_sysmips(int cmd, int arg1, int arg2,
}
case MIPS_ATOMIC_SET: {
- unsigned int tmp;
+ int tmp1;
p = (int *) arg1;
errno = verify_area(VERIFY_WRITE, p, sizeof(*p));
if (errno)
return errno;
+
errno = 0;
+#ifndef CONFIG_CPU_HAS_LLSC
+
+ save_and_cli(tmp1);
+ errno |= __get_user(tmp, p);
+ errno |= __put_user(arg2, p);
+ restore_flags(tmp1);
+
+#else /* CONFIG_CPU_HAS_LLSC */
+
__asm__(".set\tpush\t\t\t# sysmips(MIPS_ATOMIC, ...)\n\t"
".set\tmips2\n\t"
".set\tnoat\n\t"
- "1:\tll\t%0, %4\n\t"
- "move\t$1, %3\n\t"
- "2:\tsc\t$1, %1\n\t"
- "beqz\t$1, 1b\n\t"
+ "1:\tll\t%0, %5\n\t"
+ "move\t%3, %4\n\t"
+ "2:\tsc\t%3, %1\n\t"
+ "beqz\t%3, 1b\n\t"
".set\tpop\n\t"
".section\t.fixup,\"ax\"\n"
"3:\tli\t%2, 1\t\t\t# error\n\t"
@@ -98,23 +108,17 @@ sys_sysmips(int cmd, int arg1, int arg2,
".word\t1b, 3b\n\t"
".word\t2b, 3b\n\t"
".previous\n\t"
- : "=&r" (tmp), "=o" (* (u32 *) p), "=r" (errno)
+ : "=&r" (tmp), "=o" (* (u32 *) p), "=r" (errno),
+ "=&r" (tmp1)
: "r" (arg2), "o" (* (u32 *) p), "2" (errno)
: "$1");
+#endif /* CONFIG_CPU_HAS_LLSC */
+
if (errno)
return -EFAULT;
- /* We're skipping error handling etc. */
- if (current->ptrace & PT_TRACESYS)
- syscall_trace();
-
- __asm__ __volatile__(
- "move\t$29, %0\n\t"
- "j\tret_from_sys_call"
- : /* No outputs */
- : "r" (&cmd));
- /* Unreached */
+ return tmp;
}
case MIPS_FIXADE:
