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Diffstat (limited to 'arch/x86/include/asm/i387.h')
-rw-r--r--arch/x86/include/asm/i387.h43
1 files changed, 21 insertions, 22 deletions
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 71c9e5183982..175adf58dd4f 100644
--- 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...
*/
@@ -305,18 +304,18 @@ static inline void kernel_fpu_end(void)
/*
* Some instructions like VIA's padlock instructions generate a spurious
* DNA fault but don't modify SSE registers. And these instructions
- * get used from interrupt context aswell. To prevent these kernel instructions
- * in interrupt context interact wrongly with other user/kernel fpu usage, we
+ * get used from interrupt context as well. To prevent these kernel instructions
+ * in interrupt context interacting wrongly with other user/kernel fpu usage, we
* should use them only in the context of irq_ts_save/restore()
*/
static inline int irq_ts_save(void)
{
/*
- * If we are in process context, we are ok to take a spurious DNA fault.
- * Otherwise, doing clts() in process context require pre-emption to
- * be disabled or some heavy lifting like kernel_fpu_begin()
+ * If in process context and not atomic, we can take a spurious DNA fault.
+ * Otherwise, doing clts() in process context requires disabling preemption
+ * or some heavy lifting like kernel_fpu_begin()
*/
- if (!in_interrupt())
+ if (!in_atomic())
return 0;
if (read_cr0() & X86_CR0_TS) {