Merge branch 'linus' into tracing/mmiotrace-mergefixups

[pandora-kernel.git] / arch / x86 / kernel / process_64.c

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index e2319f3..ea090e6 100644 (file)
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -165,7 +165,10 @@ void cpu_idle(void)
                         */
                        local_irq_disable();
                        enter_idle();
+                       /* Don't trace irqs off for idle */
+                       stop_critical_timings();
                        idle();
+                       start_critical_timings();
                        /* In many cases the interrupt that ended idle
                           has already called exit_idle. But some idle
                           loops can be woken up without interrupt. */
@@ -294,6 +297,7 @@ void flush_thread(void)
        /*
         * Forget coprocessor state..
         */
+       tsk->fpu_counter = 0;
        clear_fpu(tsk);
        clear_used_math();
 }
@@ -658,8 +662,11 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
        /* If the task has used fpu the last 5 timeslices, just do a full
         * restore of the math state immediately to avoid the trap; the
         * chances of needing FPU soon are obviously high now
+        *
+        * tsk_used_math() checks prevent calling math_state_restore(),
+        * which can sleep in the case of !tsk_used_math()
         */
-       if (next_p->fpu_counter>5)
+       if (tsk_used_math(next_p) && next_p->fpu_counter > 5)
                math_state_restore();
        return prev_p;
 }