Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86_64: fix incorrect comments
  x86: unify restore_fpu_checking
  x86_32: introduce restore_fpu_checking()

diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 71c9e51..63d1850 100644 (file)
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -67,7 +67,7 @@ static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
                     ".previous\n"
                     _ASM_EXTABLE(1b, 3b)
                     : [err] "=r" (err)
-#if 0 /* See comment in __save_init_fpu() below. */
+#if 0 /* See comment in fxsave() below. */
                     : [fx] "r" (fx), "m" (*fx), "0" (0));
 #else
                     : [fx] "cdaSDb" (fx), "m" (*fx), "0" (0));
@@ -75,14 +75,6 @@ static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
        return err;
 }
 
-static inline int restore_fpu_checking(struct task_struct *tsk)
-{
-       if (task_thread_info(tsk)->status & TS_XSAVE)
-               return xrstor_checking(&tsk->thread.xstate->xsave);
-       else
-               return fxrstor_checking(&tsk->thread.xstate->fxsave);
-}
-
 /* AMD CPUs don't save/restore FDP/FIP/FOP unless an exception
    is pending. Clear the x87 state here by setting it to fixed
    values. The kernel data segment can be sometimes 0 and sometimes
@@ -120,7 +112,7 @@ static inline int fxsave_user(struct i387_fxsave_struct __user *fx)
                     ".previous\n"
                     _ASM_EXTABLE(1b, 3b)
                     : [err] "=r" (err), "=m" (*fx)
-#if 0 /* See comment in __fxsave_clear() below. */
+#if 0 /* See comment in fxsave() below. */
                     : [fx] "r" (fx), "0" (0));
 #else
                     : [fx] "cdaSDb" (fx), "0" (0));
@@ -185,12 +177,9 @@ static inline void tolerant_fwait(void)
        asm volatile("fnclex ; fwait");
 }
 
-static inline void restore_fpu(struct task_struct *tsk)
+/* perform fxrstor iff the processor has extended states, otherwise frstor */
+static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
 {
-       if (task_thread_info(tsk)->status & TS_XSAVE) {
-               xrstor_checking(&tsk->thread.xstate->xsave);
-               return;
-       }
        /*
         * The "nop" is needed to make the instructions the same
         * length.
@@ -199,7 +188,9 @@ static inline void restore_fpu(struct task_struct *tsk)
                "nop ; frstor %1",
                "fxrstor %1",
                X86_FEATURE_FXSR,
-               "m" (tsk->thread.xstate->fxsave));
+               "m" (*fx));
+
+       return 0;
 }
 
 /* We need a safe address that is cheap to find and that is already
@@ -262,6 +253,14 @@ end:
 
 #endif /* CONFIG_X86_64 */
 
+static inline int restore_fpu_checking(struct task_struct *tsk)
+{
+       if (task_thread_info(tsk)->status & TS_XSAVE)
+               return xrstor_checking(&tsk->thread.xstate->xsave);
+       else
+               return fxrstor_checking(&tsk->thread.xstate->fxsave);
+}
+
 /*
  * Signal frame handlers...
  */

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 2310700..ede0245 100644 (file)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -839,9 +839,6 @@ asmlinkage void math_state_restore(void)
        }
 
        clts();                         /* Allow maths ops (or we recurse) */
-#ifdef CONFIG_X86_32
-       restore_fpu(tsk);
-#else
        /*
         * Paranoid restore. send a SIGSEGV if we fail to restore the state.
         */
@@ -850,7 +847,7 @@ asmlinkage void math_state_restore(void)
                force_sig(SIGSEGV, tsk);
                return;
        }
-#endif
+
        thread->status |= TS_USEDFPU;   /* So we fnsave on switch_to() */
        tsk->fpu_counter++;
 }