From f5a9f52e2c5654c3d212dbf7e7a169c60876691a Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 30 Jul 2012 14:43:03 -0700 Subject: cpu: rewrite cpu-notifier-error-inject module Rewrite existing cpu-notifier-error-inject module to use debugfs based new framework. This change removes cpu_up_prepare_error and cpu_down_prepare_error module parameters which were used to specify error code to be injected. We could keep these module parameters for backward compatibility by module_param_cb but it seems overkill for this module. This provides the ability to inject artifical errors to CPU notifier chain callbacks. It is controlled through debugfs interface under /sys/kernel/debug/notifier-error-inject/cpu If the notifier call chain should be failed with some events notified, write the error code to "actions//error". Example1: inject CPU offline error (-1 == -EPERM) # cd /sys/kernel/debug/notifier-error-inject/cpu # echo -1 > actions/CPU_DOWN_PREPARE/error # echo 0 > /sys/devices/system/cpu/cpu1/online bash: echo: write error: Operation not permitted Example2: inject CPU online error (-2 == -ENOENT) # cd /sys/kernel/debug/notifier-error-inject/cpu # echo -2 > actions/CPU_UP_PREPARE/error # echo 1 > /sys/devices/system/cpu/cpu1/online bash: echo: write error: No such file or directory Signed-off-by: Akinobu Mita Cc: Pavel Machek Cc: "Rafael J. Wysocki" 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 | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) (limited to 'lib/Kconfig.debug') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index bdee91d50a5b..20341480bb54 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1097,10 +1097,22 @@ config NOTIFIER_ERROR_INJECTION config CPU_NOTIFIER_ERROR_INJECT tristate "CPU notifier error injection module" - depends on HOTPLUG_CPU && DEBUG_KERNEL + depends on HOTPLUG_CPU && NOTIFIER_ERROR_INJECTION help This option provides a kernel module that can be used to test - the error handling of the cpu notifiers + the error handling of the cpu notifiers by injecting artifical + errors to CPU notifier chain callbacks. It is controlled through + debugfs interface under /sys/kernel/debug/notifier-error-inject/cpu + + If the notifier call chain should be failed with some events + notified, write the error code to "actions//error". + + Example: Inject CPU offline error (-1 == -EPERM) + + # cd /sys/kernel/debug/notifier-error-inject/cpu + # echo -1 > actions/CPU_DOWN_PREPARE/error + # echo 0 > /sys/devices/system/cpu/cpu1/online + bash: echo: write error: Operation not permitted To compile this code as a module, choose M here: the module will be called cpu-notifier-error-inject. -- cgit v1.2.3