summaryrefslogtreecommitdiff
path: root/libpthread/linuxthreads/sysdeps/arm/tls.h
diff options
context:
space:
mode:
authorWaldemar Brodkorb <wbx@openadk.org>2015-02-14 23:04:02 -0600
committerWaldemar Brodkorb <wbx@openadk.org>2015-02-14 23:04:02 -0600
commite1e46622ac0fce73d802fa4a8a2e83cc25cd9e7a (patch)
tree2c8d14e4dcc733f4227f0984ed05da5826b13acd /libpthread/linuxthreads/sysdeps/arm/tls.h
parent6b6ede3d15f04fe825cfa9f697507457e3640344 (diff)
Revert "resolve merge"
This reverts commit 6b6ede3d15f04fe825cfa9f697507457e3640344.
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/arm/tls.h')
-rw-r--r--libpthread/linuxthreads/sysdeps/arm/tls.h171
1 files changed, 171 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/sysdeps/arm/tls.h b/libpthread/linuxthreads/sysdeps/arm/tls.h
new file mode 100644
index 000000000..df8d97009
--- /dev/null
+++ b/libpthread/linuxthreads/sysdeps/arm/tls.h
@@ -0,0 +1,171 @@
+/* Definitions for thread-local data handling. linuxthreads/ARM version.
+ 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _TLS_H
+#define _TLS_H
+
+#ifndef __ASSEMBLER__
+
+# include <stdbool.h>
+# include <pt-machine.h>
+# include <stddef.h>
+
+/* Type for the dtv. */
+typedef union dtv
+{
+ size_t counter;
+ struct
+ {
+ void *val;
+ bool is_static;
+ } pointer;
+} dtv_t;
+
+typedef struct
+{
+ dtv_t *dtv;
+
+ /* Reserved for the thread implementation. Unused in LinuxThreads. */
+ void *private;
+} tcbhead_t;
+#endif
+
+
+/* We can support TLS only if the floating-stack support is available.
+ However, we want to compile in the support and test at runtime whether
+ the running kernel can support it or not. To avoid bothering with the
+ TLS support code at all, use configure --without-tls.
+
+ We need USE_TLS to be consistently defined, for ldsodefs.h conditionals.
+ But some of the code below can cause problems in building libpthread
+ (e.g. useldt.h will defined FLOATING_STACKS when it shouldn't). */
+
+/* LinuxThreads can only support TLS if both floating stacks and support
+ from the tools are available.
+
+ We have to define USE_TLS consistently, or ldsodefs.h will lay out types
+ differently between an NPTL build and a LinuxThreads build. It can be set
+ for libc.so and not libpthread.so, but only if we provide appropriate padding
+ in the _pthread_descr_struct.
+
+ Currently nothing defines FLOATING_STACKS. We could assume this based on
+ kernel version once the TLS patches are available in kernel.org.
+
+ To avoid bothering with the TLS support code at all, use configure
+ --without-tls. */
+
+#if defined HAVE_TLS_SUPPORT \
+ && (defined FLOATING_STACKS || !defined IS_IN_libpthread)
+
+/* Signal that TLS support is available. */
+# define USE_TLS 1
+
+/* Include padding in _pthread_descr_struct so that libc can find p_errno,
+ if libpthread will only include the padding because of the !IS_IN_libpthread
+ check. */
+#ifndef FLOATING_STACKS
+# define INCLUDE_TLS_PADDING 1
+#endif
+
+# ifndef __ASSEMBLER__
+/* Get system call information. */
+# include <sysdep.h>
+
+/* This is the size of the initial TCB. */
+# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
+
+/* Alignment requirements for the initial TCB. */
+# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
+
+/* This is the size of the TCB. */
+# define TLS_TCB_SIZE sizeof (tcbhead_t)
+
+/* Alignment requirements for the TCB. */
+# define TLS_TCB_ALIGN __alignof__ (tcbhead_t)
+
+/* This is the size we need before TCB. */
+# define TLS_PRE_TCB_SIZE sizeof (struct _pthread_descr_struct)
+
+/* The DTV is allocated at the TP; the TCB is placed elsewhere. */
+# define TLS_DTV_AT_TP 1
+
+/* Install the dtv pointer. The pointer passed is to the element with
+ index -1 which contain the length. */
+# define INSTALL_DTV(TCBP, DTVP) \
+ (((tcbhead_t *) (TCBP))->dtv = (DTVP) + 1)
+
+/* Install new dtv for current thread. */
+# define INSTALL_NEW_DTV(DTV) \
+ (((tcbhead_t *)__builtin_thread_pointer ())->dtv = (DTV))
+
+/* Return dtv of given thread descriptor. */
+# define GET_DTV(TCBP) \
+ (((tcbhead_t *) (TCBP))->dtv)
+
+/* Code to initially initialize the thread pointer. This might need
+ special attention since 'errno' is not yet available and if the
+ operation can cause a failure 'errno' must not be touched. */
+# define TLS_INIT_TP(TCBP, SECONDCALL) \
+ ({ INTERNAL_SYSCALL_DECL (err); \
+ long result_var; \
+ result_var = INTERNAL_SYSCALL_ARM (set_tls, err, 1, (TCBP)); \
+ INTERNAL_SYSCALL_ERROR_P (result_var, err) \
+ ? "unknown error" : NULL; })
+
+/* Return the address of the dtv for the current thread. */
+# define THREAD_DTV() \
+ (((tcbhead_t *)__builtin_thread_pointer ())->dtv)
+
+/* Return the thread descriptor for the current thread. */
+# undef THREAD_SELF
+# define THREAD_SELF \
+ ((pthread_descr)__builtin_thread_pointer () - 1)
+
+# undef INIT_THREAD_SELF
+# define INIT_THREAD_SELF(DESCR, NR) \
+ TLS_INIT_TP ((struct _pthread_descr_struct *)(DESCR) + 1, 0)
+
+/* Get the thread descriptor definition. */
+# include <linuxthreads/descr.h>
+
+/* ??? Generic bits of LinuxThreads may call these macros with
+ DESCR set to NULL. We are expected to be able to reference
+ the "current" value.
+
+ In our case, we'd really prefer to use DESCR, since lots of
+ PAL_code calls would be expensive. We can only trust that
+ the compiler does its job and unifies the multiple
+ __builtin_thread_pointer instances. */
+
+#define THREAD_GETMEM(descr, member) \
+ ((void) sizeof (descr), THREAD_SELF->member)
+#define THREAD_GETMEM_NC(descr, member) \
+ ((void) sizeof (descr), THREAD_SELF->member)
+#define THREAD_SETMEM(descr, member, value) \
+ ((void) sizeof (descr), THREAD_SELF->member = (value))
+#define THREAD_SETMEM_NC(descr, member, value) \
+ ((void) sizeof (descr), THREAD_SELF->member = (value))
+
+/* Initializing the thread pointer will generate a SIGILL if the syscall
+ is not available. */
+#define TLS_INIT_TP_EXPENSIVE 1
+
+# endif /* HAVE_TLS_SUPPORT */
+#endif /* __ASSEMBLER__ */
+
+#endif /* tls.h */