From: Rafael J. Wysocki Date: Thu, 30 May 2013 19:55:46 +0000 (+0200) Subject: ACPI / processor: Initialize per_cpu(processors, pr->id) properly X-Git-Url: https://rtime.felk.cvut.cz/gitweb/linux-imx.git/commitdiff_plain/2e4f1db49d97222110b6add9a2c6cf5251a41e35 ACPI / processor: Initialize per_cpu(processors, pr->id) properly Commit ac212b6 (ACPI / processor: Use common hotplug infrastructure) forgot about initializing the per-CPU 'processors' variables which lead to ACPI cpuidle failure to use C-states and caused boot slowdown on multi-CPU machines. Fix the problem by adding per_cpu(processors, pr->id) initialization to acpi_processor_add() and add make acpi_processor_remove() clean it up as appropriate. Also modify acpi_processor_stop() so that it doesn't clear per_cpu(processors, pr->id) on processor driver removal which would then cause problems to happen when the driver is loaded again. This version of the patch contains fixes from Yinghai Lu. Reported-and-tested-by: Yinghai Lu Reported-and-tested-by: Daniel Lezcano Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index 587d2af4b323..cae2641e8d84 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -29,6 +29,9 @@ ACPI_MODULE_NAME("processor"); +DEFINE_PER_CPU(struct acpi_processor *, processors); +EXPORT_PER_CPU_SYMBOL(processors); + /* -------------------------------------------------------------------------- Errata Handling -------------------------------------------------------------------------- */ @@ -387,6 +390,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device, * checks. */ per_cpu(processor_device_array, pr->id) = device; + per_cpu(processors, pr->id) = pr; dev = get_cpu_device(pr->id); ACPI_HANDLE_SET(dev, pr->handle); @@ -407,6 +411,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device, err: free_cpumask_var(pr->throttling.shared_cpu_map); device->driver_data = NULL; + per_cpu(processors, pr->id) = NULL; err_free_pr: kfree(pr); return result; @@ -441,6 +446,7 @@ static void acpi_processor_remove(struct acpi_device *device) /* Clean up. */ per_cpu(processor_device_array, pr->id) = NULL; + per_cpu(processors, pr->id) = NULL; try_offline_node(cpu_to_node(pr->id)); /* Remove the CPU. */ diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index ac28f18823b3..d93963f1e8f4 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -78,9 +78,6 @@ static struct device_driver acpi_processor_driver = { .remove = acpi_processor_stop, }; -DEFINE_PER_CPU(struct acpi_processor *, processors); -EXPORT_PER_CPU_SYMBOL(processors); - static void acpi_processor_notify(acpi_handle handle, u32 event, void *data) { struct acpi_device *device = data; @@ -268,8 +265,6 @@ static int acpi_processor_stop(struct device *dev) thermal_cooling_device_unregister(pr->cdev); pr->cdev = NULL; } - - per_cpu(processors, pr->id) = NULL; return 0; }