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-rw-r--r--arch/x86/kernel/i387.c14
1 files changed, 5 insertions, 9 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 245a71db401a..cb339097b9ea 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -22,23 +22,19 @@
22/* 22/*
23 * Were we in an interrupt that interrupted kernel mode? 23 * Were we in an interrupt that interrupted kernel mode?
24 * 24 *
25 * For now, with eagerfpu we will return interrupted kernel FPU
26 * state as not-idle. TBD: Ideally we can change the return value
27 * to something like __thread_has_fpu(current). But we need to
28 * be careful of doing __thread_clear_has_fpu() before saving
29 * the FPU etc for supporting nested uses etc. For now, take
30 * the simple route!
31 *
32 * On others, we can do a kernel_fpu_begin/end() pair *ONLY* if that 25 * On others, we can do a kernel_fpu_begin/end() pair *ONLY* if that
33 * pair does nothing at all: the thread must not have fpu (so 26 * pair does nothing at all: the thread must not have fpu (so
34 * that we don't try to save the FPU state), and TS must 27 * that we don't try to save the FPU state), and TS must
35 * be set (so that the clts/stts pair does nothing that is 28 * be set (so that the clts/stts pair does nothing that is
36 * visible in the interrupted kernel thread). 29 * visible in the interrupted kernel thread).
30 *
31 * Except for the eagerfpu case when we return 1 unless we've already
32 * been eager and saved the state in kernel_fpu_begin().
37 */ 33 */
38static inline bool interrupted_kernel_fpu_idle(void) 34static inline bool interrupted_kernel_fpu_idle(void)
39{ 35{
40 if (use_eager_fpu()) 36 if (use_eager_fpu())
41 return 0; 37 return __thread_has_fpu(current);
42 38
43 return !__thread_has_fpu(current) && 39 return !__thread_has_fpu(current) &&
44 (read_cr0() & X86_CR0_TS); 40 (read_cr0() & X86_CR0_TS);
@@ -78,8 +74,8 @@ void __kernel_fpu_begin(void)
78 struct task_struct *me = current; 74 struct task_struct *me = current;
79 75
80 if (__thread_has_fpu(me)) { 76 if (__thread_has_fpu(me)) {
81 __save_init_fpu(me);
82 __thread_clear_has_fpu(me); 77 __thread_clear_has_fpu(me);
78 __save_init_fpu(me);
83 /* We do 'stts()' in __kernel_fpu_end() */ 79 /* We do 'stts()' in __kernel_fpu_end() */
84 } else if (!use_eager_fpu()) { 80 } else if (!use_eager_fpu()) {
85 this_cpu_write(fpu_owner_task, NULL); 81 this_cpu_write(fpu_owner_task, NULL);