The acpi idle waits calls local_irq_save and then uses mwait to go into
idle. The tracer gets reenabled at local_irq_save but does not detect that
the idle allows for wake ups.
This patch adds code to disable the tracing when acpi puts the CPU to idle.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Index: linux-tip.git/drivers/acpi/processor_idle.c
===================================================================
--- linux-tip.git.orig/drivers/acpi/processor_idle.c
+++ linux-tip.git/drivers/acpi/processor_idle.c
@@ -272,6 +272,8 @@ static atomic_t c3_cpu_count;
/* Common C-state entry for C2, C3, .. */
static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
{
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
if (cstate->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cstate);
@@ -284,6 +286,7 @@ static void acpi_cstate_enter(struct acp
gets asserted in time to freeze execution properly. */
unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
}
+ start_critical_timings();
}
#endif /* !CONFIG_CPU_IDLE */
@@ -1418,6 +1421,8 @@ static inline void acpi_idle_update_bm_r
*/
static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
{
+ /* Don't trace irqs off for idle */
+ stop_critical_timings();
if (cx->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cx);
@@ -1432,6 +1437,7 @@ static inline void acpi_idle_do_entry(st
gets asserted in time to freeze execution properly. */
unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
}
+ start_critical_timings();
}
/**
--
--
