[glibc/azanella/bz12683] microblaze: Fix Race conditions in pthread cancellation [BZ#12683]

[Adhemerval Zanella <azanella@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=19f7a7c7035711e0c31085de2ac4ddd4e56542fc

commit 19f7a7c7035711e0c31085de2ac4ddd4e56542fc
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Mon Apr 3 11:25:06 2023 -0300

    microblaze: Fix Race conditions in pthread cancellation [BZ#12683]
    
    By adding the required syscall_cancel.S.
    
    Checked against a build and make check run-built-tests=no for
    microblaze-linux-gnu.

Diff:
---
 .../unix/sysv/linux/microblaze/syscall_cancel.S    | 61 ++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/sysdeps/unix/sysv/linux/microblaze/syscall_cancel.S b/sysdeps/unix/sysv/linux/microblaze/syscall_cancel.S
new file mode 100644
index 0000000000..1f9d202bf5
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/microblaze/syscall_cancel.S
@@ -0,0 +1,61 @@
+/* Cancellable syscall wrapper.  Linux/microblaze version.
+   Copyright (C) 2023 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 <sysdep.h>
+#include <descr-const.h>
+
+/* long int __syscall_cancel_arch (int *cancelhandling,
+				   long int nr,
+				   long int arg1,
+				   long int arg2,
+				   long int arg3,
+				   long int arg4,
+				   long int arg5,
+				   long int arg6)  */
+
+ENTRY (__syscall_cancel_arch)
+
+	.globl __syscall_cancel_arch_start
+__syscall_cancel_arch_start:
+
+	lwi	r3,r5,0
+	andi	r3,r3,TCB_CANCELED_BITMASK
+	bneid	r3,1f
+	addk	r12,r6,r0
+
+	addk	r5,r7,r0
+	addk	r6,r8,r0
+	addk	r7,r9,r0
+	addk	r8,r10,r0
+	lwi	r9,r1,56
+	lwi	r10,r1,60
+	brki	r14,8
+
+	.globl __syscall_cancel_arch_end
+__syscall_cancel_arch_end:
+
+	nop
+	lwi	r15,r1,0
+	rtsd	r15,8
+	addik	r1,r1,28
+
+1:
+	brlid	r15, __syscall_do_cancel
+	nop
+
+END (__syscall_cancel_arch)