Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull smp/hotplug updates from Thomas Gleixner:
"No functional changes, just removal of obsolete and outdated defines,
macros and documentation"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Get rid of CPU hotplug notifier leftovers
cpu/hotplug: Remove obsolete notifier macros
diff --git a/Documentation/fault-injection/notifier-error-inject.txt b/Documentation/fault-injection/notifier-error-inject.txt
index 83d3f4e..e861d76 100644
--- a/Documentation/fault-injection/notifier-error-inject.txt
+++ b/Documentation/fault-injection/notifier-error-inject.txt
@@ -6,41 +6,11 @@
notifier call chain failures which is rarely executed. There are kernel
modules that can be used to test the following notifiers.
- * CPU notifier
* PM notifier
* Memory hotplug notifier
* powerpc pSeries reconfig notifier
* Netdevice notifier
-CPU notifier error injection module
------------------------------------
-This feature can be used to test the error handling of the CPU notifiers by
-injecting artificial errors to CPU notifier chain callbacks.
-
-If the notifier call chain should be failed with some events notified, write
-the error code to debugfs interface
-/sys/kernel/debug/notifier-error-inject/cpu/actions/<notifier event>/error
-
-Possible CPU notifier events to be failed are:
-
- * CPU_UP_PREPARE
- * CPU_UP_PREPARE_FROZEN
- * CPU_DOWN_PREPARE
- * CPU_DOWN_PREPARE_FROZEN
-
-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)
-
- # echo -2 > actions/CPU_UP_PREPARE/error
- # echo 1 > /sys/devices/system/cpu/cpu1/online
- bash: echo: write error: No such file or directory
-
PM notifier error injection module
----------------------------------
This feature is controlled through debugfs interface
diff --git a/Documentation/power/suspend-and-cpuhotplug.txt b/Documentation/power/suspend-and-cpuhotplug.txt
index 2fc9095..31abd04 100644
--- a/Documentation/power/suspend-and-cpuhotplug.txt
+++ b/Documentation/power/suspend-and-cpuhotplug.txt
@@ -232,7 +232,7 @@
hibernate/restore cycle.]
In the current design of the kernel however, during a CPU offline operation
- as part of the suspend/hibernate cycle (the CPU_DEAD_FROZEN notification),
+ as part of the suspend/hibernate cycle (cpuhp_tasks_frozen is set),
the existing copy of microcode image in the kernel is not freed up.
And during the CPU online operations (during resume/restore), since the
kernel finds that it already has copies of the microcode images for all the
@@ -252,10 +252,9 @@
the _cpu_down() and _cpu_up() functions is *always* 0.
This might not reflect the true current state of the system, since the
tasks could have been frozen by an out-of-band event such as a suspend
- operation in progress. Hence, it will lead to wrong notifications being
- sent during the cpu online/offline events (eg, CPU_ONLINE notification
- instead of CPU_ONLINE_FROZEN) which in turn will lead to execution of
- inappropriate code by the callbacks registered for such CPU hotplug events.
+ operation in progress. Hence, the cpuhp_tasks_frozen variable will not
+ reflect the frozen state and the CPU hotplug callbacks which evaluate
+ that variable might execute the wrong code path.
2. If a regular CPU hotplug stress test happens to race with the freezer due
to a suspend operation in progress at the same time, then we could hit the
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 938ea8a..a04ef7c1 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -56,27 +56,17 @@ extern void unregister_cpu(struct cpu *cpu);
extern ssize_t arch_cpu_probe(const char *, size_t);
extern ssize_t arch_cpu_release(const char *, size_t);
#endif
-struct notifier_block;
-#define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */
-#define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */
-#define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */
-#define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug
- * lock is dropped */
-#define CPU_BROKEN 0x000B /* CPU (unsigned)v did not die properly,
- * perhaps due to preemption. */
-
-/* Used for CPU hotplug events occurring while tasks are frozen due to a suspend
- * operation in progress
+/*
+ * These states are not related to the core CPU hotplug mechanism. They are
+ * used by various (sub)architectures to track internal state
*/
-#define CPU_TASKS_FROZEN 0x0010
-
-#define CPU_ONLINE_FROZEN (CPU_ONLINE | CPU_TASKS_FROZEN)
-#define CPU_UP_PREPARE_FROZEN (CPU_UP_PREPARE | CPU_TASKS_FROZEN)
-#define CPU_UP_CANCELED_FROZEN (CPU_UP_CANCELED | CPU_TASKS_FROZEN)
-#define CPU_DOWN_PREPARE_FROZEN (CPU_DOWN_PREPARE | CPU_TASKS_FROZEN)
-#define CPU_DOWN_FAILED_FROZEN (CPU_DOWN_FAILED | CPU_TASKS_FROZEN)
-#define CPU_DEAD_FROZEN (CPU_DEAD | CPU_TASKS_FROZEN)
+#define CPU_ONLINE 0x0002 /* CPU is up */
+#define CPU_UP_PREPARE 0x0003 /* CPU coming up */
+#define CPU_DEAD 0x0007 /* CPU dead */
+#define CPU_DEAD_FROZEN 0x0008 /* CPU timed out on unplug */
+#define CPU_POST_DEAD 0x0009 /* CPU successfully unplugged */
+#define CPU_BROKEN 0x000B /* CPU did not die properly */
#ifdef CONFIG_SMP
extern bool cpuhp_tasks_frozen;