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authorRoland McGrath <roland@hack.frob.com>2014-06-12 10:08:24 -0700
committerRoland McGrath <roland@hack.frob.com>2014-06-12 10:08:24 -0700
commitf6b07b3d48eb1d28d033b2c342a8a5571dca2e18 (patch)
treeb17d612816248611d12d049466a5b524d32f97a0 /sysdeps/i386/nptl/tls.h
parent45262aeedf2f56dcd3b30e37630ea85bb4f55603 (diff)
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Move i386 code out of nptl/ subdirectory.
Diffstat (limited to 'sysdeps/i386/nptl/tls.h')
-rw-r--r--sysdeps/i386/nptl/tls.h488
1 files changed, 488 insertions, 0 deletions
diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h
new file mode 100644
index 0000000000..ac9c9a22f9
--- /dev/null
+++ b/sysdeps/i386/nptl/tls.h
@@ -0,0 +1,488 @@
+/* Definition for thread-local data handling.  nptl/i386 version.
+   Copyright (C) 2002-2014 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)
+
+#define THREAD_SELF_SYSINFO	THREAD_GETMEM (THREAD_SELF, header.sysinfo)
+#define THREAD_SYSINFO(pd)	((pd)->header.sysinfo)
+
+/* 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
+
+
+# ifndef __NR_set_thread_area
+#  define __NR_set_thread_area 243
+# endif
+# ifndef TLS_FLAG_WRITABLE
+#  define TLS_FLAG_WRITABLE		0x00000001
+# endif
+
+// XXX Enable for the real world.
+#if 0
+# ifndef __ASSUME_SET_THREAD_AREA
+#  error "we need set_thread_area"
+# endif
+#endif
+
+# ifdef __PIC__
+#  define TLS_EBX_ARG "r"
+#  define TLS_LOAD_EBX "xchgl %3, %%ebx\n\t"
+# else
+#  define TLS_EBX_ARG "b"
+#  define TLS_LOAD_EBX
+# endif
+
+#if defined NEED_DL_SYSINFO
+# define INIT_SYSINFO \
+  _head->sysinfo = GLRO(dl_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.  */						      \
+     asm volatile (TLS_LOAD_EBX						      \
+		   "int $0x80\n\t"					      \
+		   TLS_LOAD_EBX						      \
+		   : "=a" (_result), "=m" (_segdescr.desc.entry_number)	      \
+		   : "0" (__NR_set_thread_area),			      \
+		     TLS_EBX_ARG (&_segdescr.desc), "m" (_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; })
+
+
+/* Same as THREAD_SETMEM, but the member offset can be non-constant.  */
+# 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));	      \
+       }})
+
+
+/* Set member of the thread descriptor directly.  */
+# 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 */