x86/mwait: remove unneeded local variables

Remove the eax and cstate local variables, the same can be directly
fetched from acpi_processor_cx without any transformations.

No functional change.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

diff --git a/xen/arch/x86/cpu/mwait-idle.c b/xen/arch/x86/cpu/mwait-idle.c
index 52eab81bf8f227e594573ae5fa7c6fde5e719da1..8add13d698f7b1eae1385ca882ec4f9b9f630863 100644 (file)
--- a/xen/arch/x86/cpu/mwait-idle.c
+++ b/xen/arch/x86/cpu/mwait-idle.c
@@ -721,7 +721,7 @@ static void mwait_idle(void)
        unsigned int cpu = smp_processor_id();
        struct acpi_processor_power *power = processor_powers[cpu];
        struct acpi_processor_cx *cx = NULL;
-       unsigned int eax, next_state, cstate;
+       unsigned int next_state;
        u64 before, after;
        u32 exp = 0, pred = 0, irq_traced[4] = { 0 };
 
@@ -773,9 +773,6 @@ static void mwait_idle(void)
        if ((cx->type >= 3) && errata_c6_workaround())
                cx = power->safe_state;
 
-       eax = cx->address;
-       cstate = ((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1;
-
 #if 0 /* XXX Can we/do we need to do something similar on Xen? */
        /*
         * leave_mm() to avoid costly and often unnecessary wakeups
@@ -785,7 +782,7 @@ static void mwait_idle(void)
                leave_mm(cpu);
 #endif
 
-       if (!(lapic_timer_reliable_states & (1 << cstate)))
+       if (!(lapic_timer_reliable_states & (1 << cx->type)))
                lapic_timer_off();
 
        before = alternative_call(cpuidle_get_tick);
@@ -794,7 +791,7 @@ static void mwait_idle(void)
        update_last_cx_stat(power, cx, before);
 
        if (cpu_is_haltable(cpu))
-               mwait_idle_with_hints(eax, MWAIT_ECX_INTERRUPT_BREAK);
+               mwait_idle_with_hints(cx->address, MWAIT_ECX_INTERRUPT_BREAK);
 
        after = alternative_call(cpuidle_get_tick);
 
@@ -807,7 +804,7 @@ static void mwait_idle(void)
        update_idle_stats(power, cx, before, after);
        local_irq_enable();
 
-       if (!(lapic_timer_reliable_states & (1 << cstate)))
+       if (!(lapic_timer_reliable_states & (1 << cx->type)))
                lapic_timer_on();
 
        rcu_idle_exit(cpu);