linux/drivers/acpi/processor_idle.c, branch v4.0

cpuidle: ACPI: do not overwrite name and description of C0

2015-04-03T11:18:25Z

Fix a bug that leads to showing the name and description of C-state C0 as "" in sysfs after the ACPI C-states changed (e.g. after AC->DC or DC->AC transition). The function poll_idle_init() in drivers/cpuidle/driver.c initializes the state 0 during cpuidle_register_driver(), so we better do not overwrite it again with '\0' during acpi_processor_cst_has_changed(). Signed-off-by: Thomas Schlichter Reviewed-by: Bartlomiej Zolnierkiewicz Cc: 3.13+ # 3.13+ Signed-off-by: Rafael J. Wysocki

ACPI / idle: Implement ->enter_freeze callback routine

2015-02-15T18:40:10Z

Add an ->enter_freeze callback routine, acpi_idle_enter_freeze(), to the ACPI cpuidle driver and point ->enter_freeze to it for all the C2-type and C3-type states that don't need to fall back to C1 (which may be halt-induced and that will re-enable interrupts on exit from idle, which ->enter_freeze cannot do). Signed-off-by: Rafael J. Wysocki Acked-by: Peter Zijlstra (Intel)

ACPI / cpuidle: Common callback routine for entering states

2015-02-03T20:55:11Z

Introduce a common ->enter callback routine for the ACPI cpuidle driver, acpi_idle_enter(), which helps to reduce code complexity, size and duplication and prevents theoretically possible failues that an incorrect routine may be run to enter the given idle state due to a firmware bug (eg. when _CST returns a different set of states for each processor). Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Merge acpi_idle_enter_c1() and acpi_idle_enter_simple()

2015-02-03T20:54:48Z

acpi_idle_enter_c1() and acpi_idle_enter_simple() are close enough to each other that they can be merged into one function which reduces duplication of code quite a bit. Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Drop flags.bm_check tests from acpi_idle_enter_bm()

2015-02-02T22:56:03Z

Since acpi_idle_enter_bm() is only used if flags.bm_check is set for the given acpi_processor object, it doesn't make sense to check that flag in there. For this reason, drop flags.bm_check tests (and some code depending on them) from acpi_idle_enter_bm(). Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Clean up white space in a switch statement

2015-02-02T22:55:55Z

White space in the switch statement in acpi_processor_setup_cpuidle_states() does not adhere to the kernel coding style and that makes the code difficult to read. Clean that up. Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Drop irrelevant comment from acpi_idle_enter_simple()

2015-02-02T22:55:47Z

The comment about bus master disable in acpi_idle_enter_simple() is irrelevant, because the function doesn't disable bus mastering, so drop it. Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Clean up fallback to C1 checks

2015-02-02T22:55:42Z

acpi_idle_enter_simple() and acpi_idle_enter_bm() both check if C2/C3 type entry is supported on MP in the same way, so move those checks to a separate function and call it from both places (and it doesn't need to check if the state type is not C1, because the functions in question won't be called otherwise). While at it, use IS_ENABLED() for the CONFIG_HOTPLUG_CPU check. Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Drop unnecessary calls from ->enter callback routines

2015-02-02T22:55:17Z

acpi_idle_enter_simple() and acpi_idle_enter_bm() don't need to call sched_clock_idle_sleep/wakeup_event(), because that's taken care of by the core already. Namely, sched_clock_idle_sleep_event() is called by tick_nohz_start_idle() called by __tick_nohz_idle_enter() which in turn is called by tick_nohz_idle_enter() and that is called by cpu_idle_loop(). Analogously for sched_clock_idle_wakeup_event(). For this reason, drop those calls from the ACPI cpuidle driver's ->enter callback routines. Signed-off-by: Rafael J. Wysocki

ACPI / cpuidle: Drop unnecessary calls from acpi_idle_do_entry()

2015-02-02T22:55:08Z

Since the cpuidle core calls stop_critical_timings() and start_critical_timings() around the execution of ->enter callbacks, acpi_idle_do_entry() doesn't need to do that (and really shouldn't). Also using "inline" on it is pointless and the kerneldoc entry does not reflect the actual situation any more. Fix all of the above. Signed-off-by: Rafael J. Wysocki