2014-06-03 Richard Henderson <rth@redhat.com>
+ * sysdeps/unix/sysv/linux/aarch64/pt-vfork.c: New file.
+ * sysdeps/unix/sysv/linux/aarch64/nptl/pt-vfork.S: Remove file.
+ * sysdeps/unix/sysv/linux/aarch64/vfork.S (__vfork): Incorporate
+ SAVE_PID and RESTORE_PID blocks from pt-vfork.S. Map 0 to INT_MIN
+ in the SAVE_PID block.
+ (__libc_vfork): New alias.
+
* sysdeps/unix/sysv/linux/aarch64/clone.S (__clone): Save args for
child in registers, not on the stack. Remove RESET_PID conditionals.
* sysdeps/unix/sysv/linux/aarch64/nptl/clone.S: Remove file.
+++ /dev/null
-/* Copyright (C) 2009-2014 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
- <http://www.gnu.org/licenses/>. */
-
-#include <tcb-offsets.h>
-
-/* Save the PID value. */
-#define SAVE_PID \
- mrs x2, tpidr_el0; \
- sub x2, x2, #PTHREAD_SIZEOF; \
- ldr w3, [x2, #PTHREAD_PID_OFFSET]; \
- neg w0, w3; \
- str w0, [x2, #PTHREAD_PID_OFFSET]
-
-/* Restore the old PID value in the parent. */
-#define RESTORE_PID \
- cbz x0, 1f; \
- str w3, [x2, #PTHREAD_PID_OFFSET]; \
-1:
-
-#include "../vfork.S"
--- /dev/null
+/* vfork ABI-compatibility entry points for libpthread.
+ Copyright (C) 2014 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <shlib-compat.h>
+
+/* libpthread used to have its own vfork implementation that differed
+ from libc's only in having a pointless micro-optimization. There
+ is no longer any use to having a separate copy in libpthread, but
+ the historical ABI requires it. For static linking, there is no
+ need to provide anything here--the libc version will be linked in.
+ For shared library ABI compatibility, there must be __vfork and
+ vfork symbols in libpthread.so. */
+
+#if HAVE_IFUNC
+# include <nptl/pt-vfork.c>
+#elif (SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_20) \
+ || SHLIB_COMPAT (libpthread, GLIBC_2_1_2, GLIBC_2_20))
+
+/* Thankfully, on AArch64 we can rely on the compiler generating
+ a tail call here. */
+
+extern void __libc_vfork (void);
+
+void
+vfork_compat (void)
+{
+ __libc_vfork ();
+}
+
+# if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_20)
+compat_symbol (libpthread, vfork_compat, vfork, GLIBC_2_0);
+# endif
+
+# if SHLIB_COMPAT (libpthread, GLIBC_2_1_2, GLIBC_2_20)
+strong_alias (vfork_compat, vfork_compat2)
+compat_symbol (libpthread, vfork_compat2, __vfork, GLIBC_2_1_2);
+# endif
+
+#endif
ENTRY (__vfork)
-#ifdef SAVE_PID
- SAVE_PID
-#endif
+ /* Save the TCB-cached PID away in w3, and then negate the TCB
+ field. But if it's zero, set it to 0x80000000 instead. See
+ raise.c for the logic that relies on this value. */
+ mrs x2, tpidr_el0
+ sub x2, x2, #PTHREAD_SIZEOF
+ ldr w3, [x2, #PTHREAD_PID_OFFSET]
+ mov w1, #0x80000000
+ negs w0, w3
+ csel w0, w1, w0, eq
+ str w0, [x2, #PTHREAD_PID_OFFSET]
+
mov x0, #0x4111 /* CLONE_VM | CLONE_VFORK | SIGCHLD */
mov x1, sp
DO_CALL (clone, 2)
-#ifdef RESTORE_PID
- RESTORE_PID
-#endif
+
+ /* Restore the original value of the TCB cache of the PID, if we're
+ the parent. But in the child (syscall return value equals zero),
+ leave things as they are. */
+ cbz x0, 1f
+ str w3, [x2, #PTHREAD_PID_OFFSET]
+1:
cmn x0, #4095
- b.cs 1f
+ b.cs .Lsyscall_error
RET
-1:
- b SYSCALL_ERROR
PSEUDO_END (__vfork)
libc_hidden_def (__vfork)
weak_alias (__vfork, vfork)
+strong_alias (__vfork, __libc_vfork)
git://sourceware.org / glibc.git / commitdiff