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-rw-r--r--sysdeps/unix/sysv/linux/sys/rseq.h203
1 files changed, 0 insertions, 203 deletions
diff --git a/sysdeps/unix/sysv/linux/sys/rseq.h b/sysdeps/unix/sysv/linux/sys/rseq.h
deleted file mode 100644
index 55090f9e30..0000000000
--- a/sysdeps/unix/sysv/linux/sys/rseq.h
+++ /dev/null
@@ -1,203 +0,0 @@
-/* Restartable Sequences exported symbols. Linux header.
- Copyright (C) 2020 Free Software Foundation, Inc.
-
- 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
- <https://www.gnu.org/licenses/>. */
-
-#ifndef _SYS_RSEQ_H
-#define _SYS_RSEQ_H 1
-
-/* Architecture-specific rseq signature. */
-#include <bits/rseq.h>
-
-#include <stdint.h>
-#include <sys/cdefs.h>
-
-#ifdef __has_include
-# if __has_include ("linux/rseq.h")
-# define __GLIBC_HAVE_KERNEL_RSEQ
-# endif
-#else
-# include <linux/version.h>
-# if LINUX_VERSION_CODE >= KERNEL_VERSION (4, 18, 0)
-# define __GLIBC_HAVE_KERNEL_RSEQ
-# endif
-#endif
-
-/* Rely on GNU extensions for older standards and tls model. */
-#ifdef __GNUC__
-# define __rseq_tls_model_ie __attribute__ ((__tls_model__ ("initial-exec")))
-#else
-/* Specifying the TLS model on the declaration is optional. */
-# define __rseq_tls_model_ie /* Nothing. */
-#endif
-
-#ifdef __cplusplus
-# if __cplusplus >= 201103L
-# define __rseq_tls_storage_class thread_local
-# endif
-#elif (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) >= 201112L
-# define __rseq_tls_storage_class _Thread_local
-#endif
-
-/* Fall back to __thread for TLS storage class. */
-#ifndef __rseq_tls_storage_class
-# define __rseq_tls_storage_class __thread
-#endif
-
-#ifdef __GLIBC_HAVE_KERNEL_RSEQ
-/* We use the structures declarations from the kernel headers. */
-# include <linux/rseq.h>
-#else /* __GLIBC_HAVE_KERNEL_RSEQ */
-/* We use a copy of the include/uapi/linux/rseq.h kernel header. */
-
-# include <asm/byteorder.h>
-
-enum rseq_cpu_id_state
- {
- RSEQ_CPU_ID_UNINITIALIZED = -1,
- RSEQ_CPU_ID_REGISTRATION_FAILED = -2,
- };
-
-enum rseq_flags
- {
- RSEQ_FLAG_UNREGISTER = (1 << 0),
- };
-
-enum rseq_cs_flags_bit
- {
- RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT = 0,
- RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT = 1,
- RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT = 2,
- };
-
-enum rseq_cs_flags
- {
- RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT =
- (1U << RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT),
- RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL =
- (1U << RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT),
- RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE =
- (1U << RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT),
- };
-
-/* struct rseq_cs is aligned on 32 bytes to ensure it is always
- contained within a single cache-line. It is usually declared as
- link-time constant data. */
-struct rseq_cs
- {
- /* Version of this structure. */
- uint32_t version;
- /* enum rseq_cs_flags. */
- uint32_t flags;
- uint64_t start_ip;
- /* Offset from start_ip. */
- uint64_t post_commit_offset;
- uint64_t abort_ip;
- } __attribute__ ((__aligned__ (32)));
-
-/* struct rseq is aligned on 32 bytes to ensure it is always
- contained within a single cache-line.
-
- A single struct rseq per thread is allowed. */
-struct rseq
- {
- /* Restartable sequences cpu_id_start field. Updated by the
- kernel. Read by user-space with single-copy atomicity
- semantics. This field should only be read by the thread which
- registered this data structure. Aligned on 32-bit. Always
- contains a value in the range of possible CPUs, although the
- value may not be the actual current CPU (e.g. if rseq is not
- initialized). This CPU number value should always be compared
- against the value of the cpu_id field before performing a rseq
- commit or returning a value read from a data structure indexed
- using the cpu_id_start value. */
- uint32_t cpu_id_start;
- /* Restartable sequences cpu_id field. Updated by the kernel.
- Read by user-space with single-copy atomicity semantics. This
- field should only be read by the thread which registered this
- data structure. Aligned on 32-bit. Values
- RSEQ_CPU_ID_UNINITIALIZED and RSEQ_CPU_ID_REGISTRATION_FAILED
- have a special semantic: the former means "rseq uninitialized",
- and latter means "rseq initialization failed". This value is
- meant to be read within rseq critical sections and compared
- with the cpu_id_start value previously read, before performing
- the commit instruction, or read and compared with the
- cpu_id_start value before returning a value loaded from a data
- structure indexed using the cpu_id_start value. */
- uint32_t cpu_id;
- /* Restartable sequences rseq_cs field.
-
- Contains NULL when no critical section is active for the current
- thread, or holds a pointer to the currently active struct rseq_cs.
-
- Updated by user-space, which sets the address of the currently
- active rseq_cs at the beginning of assembly instruction sequence
- block, and set to NULL by the kernel when it restarts an assembly
- instruction sequence block, as well as when the kernel detects that
- it is preempting or delivering a signal outside of the range
- targeted by the rseq_cs. Also needs to be set to NULL by user-space
- before reclaiming memory that contains the targeted struct rseq_cs.
-
- Read and set by the kernel. Set by user-space with single-copy
- atomicity semantics. This field should only be updated by the
- thread which registered this data structure. Aligned on 64-bit. */
- union
- {
- uint64_t ptr64;
-# ifdef __LP64__
- uint64_t ptr;
-# else /* __LP64__ */
- struct
- {
-# if (defined (__BYTE_ORDER) && (__BYTE_ORDER == __BIG_ENDIAN)) || defined (__BIG_ENDIAN)
- uint32_t padding; /* Initialized to zero. */
- uint32_t ptr32;
-# else /* LITTLE */
- uint32_t ptr32;
- uint32_t padding; /* Initialized to zero. */
-# endif /* ENDIAN */
- } ptr;
-# endif /* __LP64__ */
- } rseq_cs;
-
- /* Restartable sequences flags field.
-
- This field should only be updated by the thread which
- registered this data structure. Read by the kernel.
- Mainly used for single-stepping through rseq critical sections
- with debuggers.
-
- - RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT
- Inhibit instruction sequence block restart on preemption
- for this thread.
- - RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL
- Inhibit instruction sequence block restart on signal
- delivery for this thread.
- - RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE
- Inhibit instruction sequence block restart on migration for
- this thread. */
- uint32_t flags;
- } __attribute__ ((__aligned__ (32)));
-
-#endif /* __GLIBC_HAVE_KERNEL_RSEQ */
-
-/* Allocations of struct rseq and struct rseq_cs on the heap need to
- be aligned on 32 bytes. Therefore, use of malloc is discouraged
- because it does not guarantee alignment. posix_memalign should be
- used instead. */
-
-extern __rseq_tls_storage_class struct rseq __rseq_abi __rseq_tls_model_ie;
-
-#endif /* sys/rseq.h */
generated by cgit v1.2.3-70-g09d2 (git 2.50.0) at 2025-08-19 01:47:38 +0000