[13/19] nptl: microblaze: Fix Race conditions in pthread cancellation (BZ#12683)

Message ID 1513019223-7603-14-git-send-email-adhemerval.zanella@linaro.org
State New
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Series
  • nptl: Fix Race conditions in pthread cancellation (BZ#12683)
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Commit Message

Adhemerval Zanella Dec. 11, 2017, 7:06 p.m.
This patch adds the microblaze modifications required for the BZ#12683.
It basically adds the required ucontext_get_pc function.

Microblaze requires an arch specific assembly implementation because
the archicture INTERNAL_SYSCALL_NCS implementation adds a nop after
the brki instruction because the instruction expect a delay branch
slot.  I based this implementation on generated assembly using GCC 6.1.

Checked against a build and make check run-built-tests=no for
microblaze-linux-gnu.

	* sysdeps/unix/sysv/linux/microblaze/syscall_cancel.S: New file.
	* sysdeps/unix/sysv/linux/microblaze/sigcontextinfo.h
	(ucontext_get_pc): New function.

Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

---
 ChangeLog                                          |  4 ++
 .../unix/sysv/linux/microblaze/sigcontextinfo.h    | 13 +++++
 .../unix/sysv/linux/microblaze/syscall_cancel.S    | 62 ++++++++++++++++++++++
 3 files changed, 79 insertions(+)
 create mode 100644 sysdeps/unix/sysv/linux/microblaze/syscall_cancel.S

-- 
2.7.4

Patch

diff --git a/sysdeps/unix/sysv/linux/microblaze/sigcontextinfo.h b/sysdeps/unix/sysv/linux/microblaze/sigcontextinfo.h
index 145b3cb..1708937 100644
--- a/sysdeps/unix/sysv/linux/microblaze/sigcontextinfo.h
+++ b/sysdeps/unix/sysv/linux/microblaze/sigcontextinfo.h
@@ -16,6 +16,11 @@ 
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifndef _SIGCONTEXTINFO_H
+#define _SIGCONTEXTINFO_H
+
+#include <stdint.h>
+
 #define SIGCONTEXT int _code, ucontext_t *
 #define SIGCONTEXT_EXTRA_ARGS _code,
 #define GET_PC(ctx)    ((void *) (ctx)->uc_mcontext.regs.pc)
@@ -23,3 +28,11 @@ 
 #define GET_STACK(ctx) ((void *) (ctx)->uc_mcontext.regs.sp)
 #define CALL_SIGHANDLER(handler, signo, ctx) \
   (handler)((signo), SIGCONTEXT_EXTRA_ARGS (ctx))
+
+static inline uintptr_t
+ucontext_get_pc (const ucontext_t *uc)
+{
+  return uc->uc_mcontext.regs.pc;
+}
+
+#endif /* _SIGCONTEXTINFO_H  */
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 0000000..d892362
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/microblaze/syscall_cancel.S
@@ -0,0 +1,62 @@ 
+/* Cancellable syscall wrapper.  Linux/microblaze version.
+   Copyright (C) 2017 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>
+
+/* 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,r3,4 #and1
+	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)
+libc_hidden_def (__syscall_cancel_arch)
+