From dcf309974555d17019c6a8e1a425238f17990b71 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 25 Jul 2008 18:00:42 -0400 Subject: [PATCH] ftrace: disable tracing on acpi idle calls 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 Cc: Peter Zijlstra Signed-off-by: Ingo Molnar --- drivers/acpi/processor_idle.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index d592dbb1d1..b7f2963693 100644 --- a/drivers/acpi/processor_idle.c +++ b/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 acpi_processor_cx *cstate) 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_rld(struct acpi_processor *pr, */ 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(struct acpi_processor_cx *cx) gets asserted in time to freeze execution properly. */ unused = inl(acpi_gbl_FADT.xpm_timer_block.address); } + start_critical_timings(); } /** -- 2.39.5