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-rw-r--r--sysdeps/i386/nptl/tls.h463
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diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h
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+++ b/sysdeps/i386/nptl/tls.h
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+/* Definition for thread-local data handling. nptl/i386 version.
+ Copyright (C) 2002-2015 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 1
+
+#include <dl-sysdep.h>
+#ifndef __ASSEMBLER__
+# include <stdbool.h>
+# include <stddef.h>
+# include <stdint.h>
+# include <stdlib.h>
+# include <sysdep.h>
+# include <libc-internal.h>
+# include <kernel-features.h>
+
+
+/* Type for the dtv. */
+typedef union dtv
+{
+ size_t counter;
+ struct
+ {
+ void *val;
+ bool is_static;
+ } pointer;
+} dtv_t;
+
+
+typedef struct
+{
+ void *tcb; /* Pointer to the TCB. Not necessarily the
+ thread descriptor used by libpthread. */
+ dtv_t *dtv;
+ void *self; /* Pointer to the thread descriptor. */
+ int multiple_threads;
+ uintptr_t sysinfo;
+ uintptr_t stack_guard;
+ uintptr_t pointer_guard;
+ int gscope_flag;
+#ifndef __ASSUME_PRIVATE_FUTEX
+ int private_futex;
+#else
+ int __glibc_reserved1;
+#endif
+ /* Reservation of some values for the TM ABI. */
+ void *__private_tm[4];
+ /* GCC split stack support. */
+ void *__private_ss;
+} tcbhead_t;
+
+# define TLS_MULTIPLE_THREADS_IN_TCB 1
+
+#else /* __ASSEMBLER__ */
+# include <tcb-offsets.h>
+#endif
+
+
+/* Alignment requirement for the stack. For IA-32 this is governed by
+ the SSE memory functions. */
+#define STACK_ALIGN 16
+
+#ifndef __ASSEMBLER__
+/* Get system call information. */
+# include <sysdep.h>
+
+/* The old way: using LDT. */
+
+/* Structure passed to `modify_ldt', 'set_thread_area', and 'clone' calls. */
+struct user_desc
+{
+ unsigned int entry_number;
+ unsigned long int base_addr;
+ unsigned int limit;
+ unsigned int seg_32bit:1;
+ unsigned int contents:2;
+ unsigned int read_exec_only:1;
+ unsigned int limit_in_pages:1;
+ unsigned int seg_not_present:1;
+ unsigned int useable:1;
+ unsigned int empty:25;
+};
+
+/* Initializing bit fields is slow. We speed it up by using a union. */
+union user_desc_init
+{
+ struct user_desc desc;
+ unsigned int vals[4];
+};
+
+
+/* This is the size of the initial TCB. Can't be just sizeof (tcbhead_t),
+ because NPTL getpid, __libc_alloca_cutoff etc. need (almost) the whole
+ struct pthread even when not linked with -lpthread. */
+# define TLS_INIT_TCB_SIZE sizeof (struct pthread)
+
+/* Alignment requirements for the initial TCB. */
+# define TLS_INIT_TCB_ALIGN __alignof__ (struct pthread)
+
+/* This is the size of the TCB. */
+# define TLS_TCB_SIZE sizeof (struct pthread)
+
+/* Alignment requirements for the TCB. */
+# define TLS_TCB_ALIGN __alignof__ (struct pthread)
+
+/* The TCB can have any size and the memory following the address the
+ thread pointer points to is unspecified. Allocate the TCB there. */
+# define TLS_TCB_AT_TP 1
+# define TLS_DTV_AT_TP 0
+
+/* Get the thread descriptor definition. */
+# include <nptl/descr.h>
+
+
+/* Install the dtv pointer. The pointer passed is to the element with
+ index -1 which contain the length. */
+# define INSTALL_DTV(descr, dtvp) \
+ ((tcbhead_t *) (descr))->dtv = (dtvp) + 1
+
+/* Install new dtv for current thread. */
+# define INSTALL_NEW_DTV(dtvp) \
+ ({ struct pthread *__pd; \
+ THREAD_SETMEM (__pd, header.dtv, (dtvp)); })
+
+/* Return dtv of given thread descriptor. */
+# define GET_DTV(descr) \
+ (((tcbhead_t *) (descr))->dtv)
+
+/* Macros to load from and store into segment registers. */
+# ifndef TLS_GET_GS
+# define TLS_GET_GS() \
+ ({ int __seg; __asm ("movw %%gs, %w0" : "=q" (__seg)); __seg & 0xffff; })
+# endif
+# ifndef TLS_SET_GS
+# define TLS_SET_GS(val) \
+ __asm ("movw %w0, %%gs" :: "q" (val))
+# endif
+
+#ifdef NEED_DL_SYSINFO
+# define INIT_SYSINFO \
+ _head->sysinfo = GLRO(dl_sysinfo)
+# define SETUP_THREAD_SYSINFO(pd) \
+ ((pd)->header.sysinfo = THREAD_GETMEM (THREAD_SELF, header.sysinfo))
+# define CHECK_THREAD_SYSINFO(pd) \
+ assert ((pd)->header.sysinfo == THREAD_GETMEM (THREAD_SELF, header.sysinfo))
+#else
+# define INIT_SYSINFO
+#endif
+
+#ifndef LOCK_PREFIX
+# ifdef UP
+# define LOCK_PREFIX /* nothing */
+# else
+# define LOCK_PREFIX "lock;"
+# endif
+#endif
+
+static inline void __attribute__ ((unused, always_inline))
+tls_fill_user_desc (union user_desc_init *desc,
+ unsigned int entry_number,
+ void *pd)
+{
+ desc->vals[0] = entry_number;
+ /* The 'base_addr' field. Pointer to the TCB. */
+ desc->vals[1] = (unsigned long int) pd;
+ /* The 'limit' field. We use 4GB which is 0xfffff pages. */
+ desc->vals[2] = 0xfffff;
+ /* Collapsed value of the bitfield:
+ .seg_32bit = 1
+ .contents = 0
+ .read_exec_only = 0
+ .limit_in_pages = 1
+ .seg_not_present = 0
+ .useable = 1 */
+ desc->vals[3] = 0x51;
+}
+
+/* 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(thrdescr) \
+ ({ void *_thrdescr = (thrdescr); \
+ tcbhead_t *_head = _thrdescr; \
+ union user_desc_init _segdescr; \
+ int _result; \
+ \
+ _head->tcb = _thrdescr; \
+ /* For now the thread descriptor is at the same address. */ \
+ _head->self = _thrdescr; \
+ /* New syscall handling support. */ \
+ INIT_SYSINFO; \
+ \
+ /* Let the kernel pick a value for the 'entry_number' field. */ \
+ tls_fill_user_desc (&_segdescr, -1, _thrdescr); \
+ \
+ /* Install the TLS. */ \
+ INTERNAL_SYSCALL_DECL (err); \
+ _result = INTERNAL_SYSCALL (set_thread_area, err, 1, &_segdescr.desc); \
+ \
+ if (_result == 0) \
+ /* We know the index in the GDT, now load the segment register. \
+ The use of the GDT is described by the value 3 in the lower \
+ three bits of the segment descriptor value. \
+ \
+ Note that we have to do this even if the numeric value of \
+ the descriptor does not change. Loading the segment register \
+ causes the segment information from the GDT to be loaded \
+ which is necessary since we have changed it. */ \
+ TLS_SET_GS (_segdescr.desc.entry_number * 8 + 3); \
+ \
+ _result == 0 ? NULL \
+ : "set_thread_area failed when setting up thread-local storage\n"; })
+
+# define TLS_DEFINE_INIT_TP(tp, pd) \
+ union user_desc_init _segdescr; \
+ /* Find the 'entry_number' field that the kernel selected in TLS_INIT_TP. \
+ The first three bits of the segment register value select the GDT, \
+ ignore them. We get the index from the value of the %gs register in \
+ the current thread. */ \
+ tls_fill_user_desc (&_segdescr, TLS_GET_GS () >> 3, pd); \
+ const struct user_desc *tp = &_segdescr.desc
+
+
+/* Return the address of the dtv for the current thread. */
+# define THREAD_DTV() \
+ ({ struct pthread *__pd; \
+ THREAD_GETMEM (__pd, header.dtv); })
+
+
+/* Return the thread descriptor for the current thread.
+
+ The contained asm must *not* be marked volatile since otherwise
+ assignments like
+ pthread_descr self = thread_self();
+ do not get optimized away. */
+# define THREAD_SELF \
+ ({ struct pthread *__self; \
+ asm ("movl %%gs:%c1,%0" : "=r" (__self) \
+ : "i" (offsetof (struct pthread, header.self))); \
+ __self;})
+
+/* Magic for libthread_db to know how to do THREAD_SELF. */
+# define DB_THREAD_SELF \
+ REGISTER_THREAD_AREA (32, offsetof (struct user_regs_struct, xgs), 3) \
+ REGISTER_THREAD_AREA (64, 26 * 8, 3) /* x86-64's user_regs_struct->gs */
+
+
+/* Read member of the thread descriptor directly. */
+# define THREAD_GETMEM(descr, member) \
+ ({ __typeof (descr->member) __value; \
+ if (sizeof (__value) == 1) \
+ asm volatile ("movb %%gs:%P2,%b0" \
+ : "=q" (__value) \
+ : "0" (0), "i" (offsetof (struct pthread, member))); \
+ else if (sizeof (__value) == 4) \
+ asm volatile ("movl %%gs:%P1,%0" \
+ : "=r" (__value) \
+ : "i" (offsetof (struct pthread, member))); \
+ else \
+ { \
+ if (sizeof (__value) != 8) \
+ /* There should not be any value with a size other than 1, \
+ 4 or 8. */ \
+ abort (); \
+ \
+ asm volatile ("movl %%gs:%P1,%%eax\n\t" \
+ "movl %%gs:%P2,%%edx" \
+ : "=A" (__value) \
+ : "i" (offsetof (struct pthread, member)), \
+ "i" (offsetof (struct pthread, member) + 4)); \
+ } \
+ __value; })
+
+
+/* Same as THREAD_GETMEM, but the member offset can be non-constant. */
+# define THREAD_GETMEM_NC(descr, member, idx) \
+ ({ __typeof (descr->member[0]) __value; \
+ if (sizeof (__value) == 1) \
+ asm volatile ("movb %%gs:%P2(%3),%b0" \
+ : "=q" (__value) \
+ : "0" (0), "i" (offsetof (struct pthread, member[0])), \
+ "r" (idx)); \
+ else if (sizeof (__value) == 4) \
+ asm volatile ("movl %%gs:%P1(,%2,4),%0" \
+ : "=r" (__value) \
+ : "i" (offsetof (struct pthread, member[0])), \
+ "r" (idx)); \
+ else \
+ { \
+ if (sizeof (__value) != 8) \
+ /* There should not be any value with a size other than 1, \
+ 4 or 8. */ \
+ abort (); \
+ \
+ asm volatile ("movl %%gs:%P1(,%2,8),%%eax\n\t" \
+ "movl %%gs:4+%P1(,%2,8),%%edx" \
+ : "=&A" (__value) \
+ : "i" (offsetof (struct pthread, member[0])), \
+ "r" (idx)); \
+ } \
+ __value; })
+
+
+
+/* Set member of the thread descriptor directly. */
+# define THREAD_SETMEM(descr, member, value) \
+ ({ if (sizeof (descr->member) == 1) \
+ asm volatile ("movb %b0,%%gs:%P1" : \
+ : "iq" (value), \
+ "i" (offsetof (struct pthread, member))); \
+ else if (sizeof (descr->member) == 4) \
+ asm volatile ("movl %0,%%gs:%P1" : \
+ : "ir" (value), \
+ "i" (offsetof (struct pthread, member))); \
+ else \
+ { \
+ if (sizeof (descr->member) != 8) \
+ /* There should not be any value with a size other than 1, \
+ 4 or 8. */ \
+ abort (); \
+ \
+ asm volatile ("movl %%eax,%%gs:%P1\n\t" \
+ "movl %%edx,%%gs:%P2" : \
+ : "A" ((uint64_t) cast_to_integer (value)), \
+ "i" (offsetof (struct pthread, member)), \
+ "i" (offsetof (struct pthread, member) + 4)); \
+ }})
+
+
+/* Same as THREAD_SETMEM, but the member offset can be non-constant. */
+# define THREAD_SETMEM_NC(descr, member, idx, value) \
+ ({ if (sizeof (descr->member[0]) == 1) \
+ asm volatile ("movb %b0,%%gs:%P1(%2)" : \
+ : "iq" (value), \
+ "i" (offsetof (struct pthread, member)), \
+ "r" (idx)); \
+ else if (sizeof (descr->member[0]) == 4) \
+ asm volatile ("movl %0,%%gs:%P1(,%2,4)" : \
+ : "ir" (value), \
+ "i" (offsetof (struct pthread, member)), \
+ "r" (idx)); \
+ else \
+ { \
+ if (sizeof (descr->member[0]) != 8) \
+ /* There should not be any value with a size other than 1, \
+ 4 or 8. */ \
+ abort (); \
+ \
+ asm volatile ("movl %%eax,%%gs:%P1(,%2,8)\n\t" \
+ "movl %%edx,%%gs:4+%P1(,%2,8)" : \
+ : "A" ((uint64_t) cast_to_integer (value)), \
+ "i" (offsetof (struct pthread, member)), \
+ "r" (idx)); \
+ }})
+
+
+/* Atomic compare and exchange on TLS, returning old value. */
+#define THREAD_ATOMIC_CMPXCHG_VAL(descr, member, newval, oldval) \
+ ({ __typeof (descr->member) __ret; \
+ __typeof (oldval) __old = (oldval); \
+ if (sizeof (descr->member) == 4) \
+ asm volatile (LOCK_PREFIX "cmpxchgl %2, %%gs:%P3" \
+ : "=a" (__ret) \
+ : "0" (__old), "r" (newval), \
+ "i" (offsetof (struct pthread, member))); \
+ else \
+ /* Not necessary for other sizes in the moment. */ \
+ abort (); \
+ __ret; })
+
+
+/* Atomic logical and. */
+#define THREAD_ATOMIC_AND(descr, member, val) \
+ (void) ({ if (sizeof ((descr)->member) == 4) \
+ asm volatile (LOCK_PREFIX "andl %1, %%gs:%P0" \
+ :: "i" (offsetof (struct pthread, member)), \
+ "ir" (val)); \
+ else \
+ /* Not necessary for other sizes in the moment. */ \
+ abort (); })
+
+
+/* Atomic set bit. */
+#define THREAD_ATOMIC_BIT_SET(descr, member, bit) \
+ (void) ({ if (sizeof ((descr)->member) == 4) \
+ asm volatile (LOCK_PREFIX "orl %1, %%gs:%P0" \
+ :: "i" (offsetof (struct pthread, member)), \
+ "ir" (1 << (bit))); \
+ else \
+ /* Not necessary for other sizes in the moment. */ \
+ abort (); })
+
+
+/* Call the user-provided thread function. */
+#define CALL_THREAD_FCT(descr) \
+ ({ void *__res; \
+ int __ignore1, __ignore2; \
+ asm volatile ("pushl %%eax\n\t" \
+ "pushl %%eax\n\t" \
+ "pushl %%eax\n\t" \
+ "pushl %%gs:%P4\n\t" \
+ "call *%%gs:%P3\n\t" \
+ "addl $16, %%esp" \
+ : "=a" (__res), "=c" (__ignore1), "=d" (__ignore2) \
+ : "i" (offsetof (struct pthread, start_routine)), \
+ "i" (offsetof (struct pthread, arg))); \
+ __res; })
+
+
+/* Set the stack guard field in TCB head. */
+#define THREAD_SET_STACK_GUARD(value) \
+ THREAD_SETMEM (THREAD_SELF, header.stack_guard, value)
+#define THREAD_COPY_STACK_GUARD(descr) \
+ ((descr)->header.stack_guard \
+ = THREAD_GETMEM (THREAD_SELF, header.stack_guard))
+
+
+/* Set the pointer guard field in the TCB head. */
+#define THREAD_SET_POINTER_GUARD(value) \
+ THREAD_SETMEM (THREAD_SELF, header.pointer_guard, value)
+#define THREAD_COPY_POINTER_GUARD(descr) \
+ ((descr)->header.pointer_guard \
+ = THREAD_GETMEM (THREAD_SELF, header.pointer_guard))
+
+
+/* Get and set the global scope generation counter in the TCB head. */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED 1
+#define THREAD_GSCOPE_FLAG_WAIT 2
+#define THREAD_GSCOPE_RESET_FLAG() \
+ do \
+ { int __res; \
+ asm volatile ("xchgl %0, %%gs:%P1" \
+ : "=r" (__res) \
+ : "i" (offsetof (struct pthread, header.gscope_flag)), \
+ "0" (THREAD_GSCOPE_FLAG_UNUSED)); \
+ if (__res == THREAD_GSCOPE_FLAG_WAIT) \
+ lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \
+ } \
+ while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+ THREAD_SETMEM (THREAD_SELF, header.gscope_flag, THREAD_GSCOPE_FLAG_USED)
+#define THREAD_GSCOPE_WAIT() \
+ GL(dl_wait_lookup_done) ()
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* tls.h */
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