From 048b9c3549790af21eabd06a5ebdad305e75b1c5 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 30 Jul 2012 14:43:07 -0700 Subject: PM: PM notifier error injection module This provides the ability to inject artifical errors to PM notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/pm Each of the files in "error" directory represents an event which can be failed and contains the error code. If the notifier call chain should be failed with some events notified, write the error code to the files. If the notifier call chain should be failed with some events notified, write the error code to "actions//error". Example: Inject PM suspend error (-12 = -ENOMEM) # cd /sys/kernel/debug/notifier-error-inject/pm # echo -12 > actions/PM_SUSPEND_PREPARE/error # echo mem > /sys/power/state bash: echo: write error: Cannot allocate memory Signed-off-by: Akinobu Mita Acked-by: "Rafael J. Wysocki" Cc: Pavel Machek Cc: Greg KH Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Dave Jones Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 24 +++++++++++++++++++++ lib/Makefile | 1 + lib/pm-notifier-error-inject.c | 49 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 74 insertions(+) create mode 100644 lib/pm-notifier-error-inject.c diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 20341480bb54..c2024d86fb12 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1119,6 +1119,30 @@ config CPU_NOTIFIER_ERROR_INJECT If unsure, say N. +config PM_NOTIFIER_ERROR_INJECT + tristate "PM notifier error injection module" + depends on PM && NOTIFIER_ERROR_INJECTION + default m if PM_DEBUG + help + This option provides the ability to inject artifical errors to + PM notifier chain callbacks. It is controlled through debugfs + interface /sys/kernel/debug/notifier-error-inject/pm + + If the notifier call chain should be failed with some events + notified, write the error code to "actions//error". + + Example: Inject PM suspend error (-12 = -ENOMEM) + + # cd /sys/kernel/debug/notifier-error-inject/pm/ + # echo -12 > actions/PM_SUSPEND_PREPARE/error + # echo mem > /sys/power/state + bash: echo: write error: Cannot allocate memory + + To compile this code as a module, choose M here: the module will + be called pm-notifier-error-inject. + + If unsure, say N. + config FAULT_INJECTION bool "Fault-injection framework" depends on DEBUG_KERNEL diff --git a/lib/Makefile b/lib/Makefile index 71acfa4489f3..c32c66473ba1 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -92,6 +92,7 @@ obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o obj-$(CONFIG_NOTIFIER_ERROR_INJECTION) += notifier-error-inject.o obj-$(CONFIG_CPU_NOTIFIER_ERROR_INJECT) += cpu-notifier-error-inject.o +obj-$(CONFIG_PM_NOTIFIER_ERROR_INJECT) += pm-notifier-error-inject.o lib-$(CONFIG_GENERIC_BUG) += bug.o diff --git a/lib/pm-notifier-error-inject.c b/lib/pm-notifier-error-inject.c new file mode 100644 index 000000000000..c094b2dedc23 --- /dev/null +++ b/lib/pm-notifier-error-inject.c @@ -0,0 +1,49 @@ +#include +#include +#include + +#include "notifier-error-inject.h" + +static int priority; +module_param(priority, int, 0); +MODULE_PARM_DESC(priority, "specify PM notifier priority"); + +static struct notifier_err_inject pm_notifier_err_inject = { + .actions = { + { NOTIFIER_ERR_INJECT_ACTION(PM_HIBERNATION_PREPARE) }, + { NOTIFIER_ERR_INJECT_ACTION(PM_SUSPEND_PREPARE) }, + { NOTIFIER_ERR_INJECT_ACTION(PM_RESTORE_PREPARE) }, + {} + } +}; + +static struct dentry *dir; + +static int err_inject_init(void) +{ + int err; + + dir = notifier_err_inject_init("pm", notifier_err_inject_dir, + &pm_notifier_err_inject, priority); + if (IS_ERR(dir)) + return PTR_ERR(dir); + + err = register_pm_notifier(&pm_notifier_err_inject.nb); + if (err) + debugfs_remove_recursive(dir); + + return err; +} + +static void err_inject_exit(void) +{ + unregister_pm_notifier(&pm_notifier_err_inject.nb); + debugfs_remove_recursive(dir); +} + +module_init(err_inject_init); +module_exit(err_inject_exit); + +MODULE_DESCRIPTION("PM notifier error injection module"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Akinobu Mita "); -- cgit v1.2.3-58-ga151