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-rw-r--r--cpukit/include/rtems/score/tls.h217
1 files changed, 217 insertions, 0 deletions
diff --git a/cpukit/include/rtems/score/tls.h b/cpukit/include/rtems/score/tls.h
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index 0000000000..644e54e6f7
--- /dev/null
+++ b/cpukit/include/rtems/score/tls.h
@@ -0,0 +1,217 @@
+/**
+ * @file
+ *
+ * @ingroup ScoreTLS
+ *
+ * @brief Thread-Local Storage (TLS)
+ */
+
+/*
+ * Copyright (c) 2014 embedded brains GmbH. All rights reserved.
+ *
+ * embedded brains GmbH
+ * Dornierstr. 4
+ * 82178 Puchheim
+ * Germany
+ * <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#ifndef _RTEMS_SCORE_TLS_H
+#define _RTEMS_SCORE_TLS_H
+
+#include <rtems/score/cpu.h>
+
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/**
+ * @defgroup ScoreTLS Thread-Local Storage (TLS)
+ *
+ * @ingroup Score
+ *
+ * @brief Thread-local storage (TLS) support.
+ *
+ * Variants I and II are according to Ulrich Drepper, "ELF Handling For
+ * Thread-Local Storage".
+ *
+ * @{
+ */
+
+extern char _TLS_Data_begin[];
+
+extern char _TLS_Data_end[];
+
+extern char _TLS_Data_size[];
+
+extern char _TLS_BSS_begin[];
+
+extern char _TLS_BSS_end[];
+
+extern char _TLS_BSS_size[];
+
+extern char _TLS_Size[];
+
+extern char _TLS_Alignment[];
+
+typedef struct {
+ /*
+ * FIXME: Not sure if the generation number type is correct for all
+ * architectures.
+ */
+ uint32_t generation_number;
+
+ void *tls_blocks[1];
+} TLS_Dynamic_thread_vector;
+
+typedef struct TLS_Thread_control_block {
+#ifdef __i386__
+ struct TLS_Thread_control_block *tcb;
+#else
+ TLS_Dynamic_thread_vector *dtv;
+ uintptr_t reserved;
+#endif
+} TLS_Thread_control_block;
+
+typedef struct {
+ uintptr_t module;
+ uintptr_t offset;
+} TLS_Index;
+
+static inline uintptr_t _TLS_Get_size( void )
+{
+ /*
+ * Do not use _TLS_Size here since this will lead GCC to assume that this
+ * symbol is not 0 and the tests for 0 will be optimized away.
+ */
+ return (uintptr_t) _TLS_BSS_end - (uintptr_t) _TLS_Data_begin;
+}
+
+static inline uintptr_t _TLS_Heap_align_up( uintptr_t val )
+{
+ uintptr_t msk = CPU_HEAP_ALIGNMENT - 1;
+
+ return (val + msk) & ~msk;
+}
+
+static inline uintptr_t _TLS_Get_thread_control_block_area_size(
+ uintptr_t alignment
+)
+{
+ return alignment <= sizeof(TLS_Thread_control_block) ?
+ sizeof(TLS_Thread_control_block) : alignment;
+}
+
+static inline uintptr_t _TLS_Get_allocation_size(
+ uintptr_t size,
+ uintptr_t alignment
+)
+{
+ uintptr_t allocation_size = 0;
+
+ allocation_size += _TLS_Heap_align_up( size );
+ allocation_size += _TLS_Get_thread_control_block_area_size( alignment );
+
+#ifndef __i386__
+ allocation_size += sizeof(TLS_Dynamic_thread_vector);
+#endif
+
+ return allocation_size;
+}
+
+static inline void *_TLS_Copy_and_clear( void *tls_area )
+{
+ tls_area = memcpy(
+ tls_area,
+ _TLS_Data_begin,
+ (size_t) ((uintptr_t)_TLS_Data_size)
+ );
+
+
+ memset(
+ (char *) tls_area + (size_t)((intptr_t) _TLS_BSS_begin) -
+ (size_t)((intptr_t) _TLS_Data_begin),
+ 0,
+ ((size_t) (intptr_t)_TLS_BSS_size)
+ );
+
+ return tls_area;
+}
+
+static inline void *_TLS_Initialize(
+ void *tls_block,
+ TLS_Thread_control_block *tcb,
+ TLS_Dynamic_thread_vector *dtv
+)
+{
+#ifdef __i386__
+ (void) dtv;
+ tcb->tcb = tcb;
+#else
+ tcb->dtv = dtv;
+ dtv->generation_number = 1;
+ dtv->tls_blocks[0] = tls_block;
+#endif
+
+ return _TLS_Copy_and_clear( tls_block );
+}
+
+/* Use Variant I, TLS offsets emitted by linker takes the TCB into account */
+static inline void *_TLS_TCB_at_area_begin_initialize( void *tls_area )
+{
+ void *tls_block = (char *) tls_area
+ + _TLS_Get_thread_control_block_area_size( (uintptr_t) _TLS_Alignment );
+ TLS_Thread_control_block *tcb = tls_area;
+ uintptr_t aligned_size = _TLS_Heap_align_up( (uintptr_t) _TLS_Size );
+ TLS_Dynamic_thread_vector *dtv = (TLS_Dynamic_thread_vector *)
+ ((char *) tls_block + aligned_size);
+
+ return _TLS_Initialize( tls_block, tcb, dtv );
+}
+
+/* Use Variant I, TLS offsets emitted by linker neglects the TCB */
+static inline void *_TLS_TCB_before_TLS_block_initialize( void *tls_area )
+{
+ void *tls_block = (char *) tls_area
+ + _TLS_Get_thread_control_block_area_size( (uintptr_t) _TLS_Alignment );
+ TLS_Thread_control_block *tcb = (TLS_Thread_control_block *)
+ ((char *) tls_block - sizeof(*tcb));
+ uintptr_t aligned_size = _TLS_Heap_align_up( (uintptr_t) _TLS_Size );
+ TLS_Dynamic_thread_vector *dtv = (TLS_Dynamic_thread_vector *)
+ ((char *) tls_block + aligned_size);
+
+ return _TLS_Initialize( tls_block, tcb, dtv );
+}
+
+/* Use Variant II */
+static inline void *_TLS_TCB_after_TLS_block_initialize( void *tls_area )
+{
+ uintptr_t size = (uintptr_t) _TLS_Size;
+ uintptr_t tls_align = (uintptr_t) _TLS_Alignment;
+ uintptr_t tls_mask = tls_align - 1;
+ uintptr_t heap_align = _TLS_Heap_align_up( tls_align );
+ uintptr_t heap_mask = heap_align - 1;
+ TLS_Thread_control_block *tcb = (TLS_Thread_control_block *)
+ ((char *) tls_area + ((size + heap_mask) & ~heap_mask));
+ void *tls_block = (char *) tcb - ((size + tls_mask) & ~tls_mask);
+ TLS_Dynamic_thread_vector *dtv = (TLS_Dynamic_thread_vector *)
+ ((char *) tcb + sizeof(*tcb));
+
+ _TLS_Initialize( tls_block, tcb, dtv );
+
+ return tcb;
+}
+
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _RTEMS_SCORE_TLS_H */