(DO_MODIFY_LDT): Move from INIT_THREAD_SELF. (INIT_THREAD_SELF): Use sys_thread_area...

diff --git a/linuxthreads/sysdeps/i386/useldt.h b/linuxthreads/sysdeps/i386/useldt.h
index 3edcdca..4fd226e 100644 (file)
--- a/linuxthreads/sysdeps/i386/useldt.h
+++ b/linuxthreads/sysdeps/i386/useldt.h
@@ -22,6 +22,7 @@
 #ifndef __ASSEMBLER__
 #include <stddef.h>    /* For offsetof.  */
 #include <stdlib.h>    /* For abort().  */
+#include <sysdep.h>    /* For INLINE_SYSCALL.  */
 
 
 /* We don't want to include the kernel header.  So duplicate the
@@ -61,24 +62,74 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t);
   __self;                                                                    \
 })
 
-/* Initialize the thread-unique value.  */
-#define INIT_THREAD_SELF(descr, nr) \
-{                                                                            \
+#define DO_MODIFY_LDT(descr, nr) \
+({                                                                           \
   struct modify_ldt_ldt_s ldt_entry =                                        \
     { nr, (unsigned long int) descr, sizeof (struct _pthread_descr_struct),   \
       1, 0, 0, 0, 0, 1, 0 };                                                 \
   if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0)                 \
     abort ();                                                                \
-  __asm__ __volatile__ ("movw %w0, %%gs" : : "q" (nr * 8 + 7));                      \
+  nr * 8 + 7;                                                                \
+})
+
+/* Initialize the thread-unique value.  */
+#ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
+#define INIT_THREAD_SELF(descr, nr) \
+{                                                                            \
+  int __gs = INLINE_SYSCALL (set_thread_area, 2, descr, 1);                  \
+  if (__gs == -1)                                                            \
+    abort ();                                                                \
+  __asm__ __volatile__ ("movw %w0, %%gs" : : "q" (__gs));                    \
 }
+#elif defined __NR_set_thread_area
+
+/* Defined in pspinlock.c.  */
+extern int __have_no_set_thread_area;
+
+#define INIT_THREAD_SELF(descr, nr) \
+{                                                                            \
+  int __gs = -1;                                                             \
+  if (! __builtin_expect (__have_no_set_thread_area, 0))                     \
+    {                                                                        \
+      if ((__gs = INLINE_SYSCALL (set_thread_area, 2, descr, 1)) == -1       \
+         && errno == ENOSYS)                                                 \
+       __have_no_set_thread_area = 1;                                        \
+    }                                                                        \
+  if (__builtin_expect (__gs == -1, 0))                                              \
+    __gs = DO_MODIFY_LDT (descr, nr);                                        \
+  __asm__ __volatile__ ("movw %w0, %%gs" : : "q" (__gs));                    \
+}
+#else
+#define INIT_THREAD_SELF(descr, nr) \
+{                                                                            \
+  int __gs = DO_MODIFY_LDT (descr, nr);                                              \
+  __asm__ __volatile__ ("movw %w0, %%gs" : : "q" (__gs));                    \
+}
+#endif
 
 /* Free resources associated with thread descriptor.  */
+#ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
+#define FREE_THREAD(descr, nr) do { } while (0)
+#elif defined __NR_set_thread_area
+#define FREE_THREAD(descr, nr) \
+{                                                                            \
+  int __gs;                                                                  \
+  __asm__ __volatile__ ("movw %%gs, %w0" : "=q" (__gs));                     \
+  if (__builtin_expect (__gs & 4, 0))                                        \
+    {                                                                        \
+      struct modify_ldt_ldt_s ldt_entry =                                    \
+       { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 };                                    \
+      __modify_ldt (1, &ldt_entry, sizeof (ldt_entry));                              \
+    }                                                                        \
+}
+#else
 #define FREE_THREAD(descr, nr) \
 {                                                                            \
   struct modify_ldt_ldt_s ldt_entry =                                        \
     { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 };                                       \
   __modify_ldt (1, &ldt_entry, sizeof (ldt_entry));                          \
 }
+#endif
 
 /* Read member of the thread descriptor directly.  */
 #define THREAD_GETMEM(descr, member) \