alpha vfork update
Richard Henderson
rth@redhat.com
Thu Mar 11 21:37:00 GMT 2004
Just like all the others. Fortunately, I do have registers that
are preserved across the syscall.
r~
* sysdeps/alpha/tcb-offsets.sym (PID_OFFSET): New.
* sysdeps/unix/sysv/linux/alpha/pt-vfork.S: Save/restore PID.
* sysdeps/unix/sysv/linux/alpha/vfork.S: New file.
Index: sysdeps/alpha/tcb-offsets.sym
===================================================================
RCS file: /cvs/glibc/libc/nptl/sysdeps/alpha/tcb-offsets.sym,v
retrieving revision 1.1
diff -c -p -d -r1.1 tcb-offsets.sym
*** sysdeps/alpha/tcb-offsets.sym 13 Jan 2004 09:36:22 -0000 1.1
--- sysdeps/alpha/tcb-offsets.sym 11 Mar 2004 21:32:30 -0000
***************
*** 10,12 ****
--- 10,13 ----
#if TLS_MULTIPLE_THREADS_IN_TCB
MULTIPLE_THREADS_OFFSET thread_offsetof (header.multiple_threads)
#endif
+ PID_OFFSET thread_offsetof (pid)
Index: sysdeps/unix/sysv/linux/alpha/pt-vfork.S
===================================================================
RCS file: /cvs/glibc/libc/nptl/sysdeps/unix/sysv/linux/alpha/pt-vfork.S,v
retrieving revision 1.1
diff -c -p -d -r1.1 pt-vfork.S
*** sysdeps/unix/sysv/linux/alpha/pt-vfork.S 1 Jul 2003 20:21:45 -0000 1.1
--- sysdeps/unix/sysv/linux/alpha/pt-vfork.S 11 Mar 2004 21:32:30 -0000
***************
*** 1,4 ****
! /* Copyright (C) 2003 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
--- 1,4 ----
! /* Copyright (C) 2003, 2004 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
***************
*** 16,25 ****
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
! #include <sysdep-cancel.h>
- PSEUDO(__vfork, vfork, 0)
- ret
PSEUDO_END (__vfork)
weak_alias (__vfork, vfork)
--- 16,43 ----
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
! #include <sysdep.h>
! #include <tcb-offsets.h>
!
! #undef PSEUDO_PREPARE_ARGS
! #define PSEUDO_PREPARE_ARGS \
! /* Load the current cached pid value across the vfork. */ \
! rduniq; \
! ldl a2, PID_OFFSET(v0); \
! mov v0, a1; \
! /* Write back its negation, to indicate that the pid value is \
! uninitialized in the the child, and in the window between \
! here and the point at which we restore the value. */ \
! negl a2, t0; \
! stl t0, PID_OFFSET(v0);
!
! PSEUDO (__vfork, vfork, 0)
!
! /* If we're back in the parent, restore the saved pid. */
! beq v0, 1f
! stl a2, PID_OFFSET(a1)
! 1: ret
PSEUDO_END (__vfork)
weak_alias (__vfork, vfork)
Index: sysdeps/unix/sysv/linux/alpha/vfork.S
===================================================================
RCS file: sysdeps/unix/sysv/linux/alpha/vfork.S
diff -N sysdeps/unix/sysv/linux/alpha/vfork.S
*** /dev/null 1 Jan 1970 00:00:00 -0000
--- sysdeps/unix/sysv/linux/alpha/vfork.S 11 Mar 2004 21:32:30 -0000
***************
*** 0 ****
--- 1,46 ----
+ /* Copyright (C) 2004 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+ #include <sysdep.h>
+ #include <tcb-offsets.h>
+
+ #undef PSEUDO_PREPARE_ARGS
+ #define PSEUDO_PREPARE_ARGS \
+ /* Load the current cached pid value across the vfork. */ \
+ rduniq; \
+ ldl a2, PID_OFFSET(v0); \
+ mov v0, a1; \
+ /* If the cached value is initialized (nonzero), then write \
+ back its negation, or INT_MIN, to indicate that the pid \
+ value is uninitialized in the the child, and in the window \
+ between here and the point at which we restore the value. */ \
+ ldah t0, -0x8000; \
+ negl a2, t1; \
+ cmovne a2, t1, t0; \
+ stl t0, PID_OFFSET(v0);
+
+ PSEUDO (__vfork, vfork, 0)
+
+ /* If we're back in the parent, restore the saved pid. */
+ beq v0, 1f
+ stl a2, PID_OFFSET(a1)
+ 1: ret
+
+ PSEUDO_END (__vfork)
+
+ weak_alias (__vfork, vfork)
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