linux_dsm_epyc7002/include/linux/cpuhotplug.h
Thomas Gleixner 5b7aa87e04 cpu/hotplug: Implement setup/removal interface
Implement function which allow to setup/remove hotplug state callbacks.

The default behaviour for setup is to call the startup function for this state
for (or on) all cpus which have a hotplug state >= the installed state.

The default behaviour for removal is to call the teardown function for this
state for (or on) all cpus which have a hotplug state >= the installed state.

This includes rollback to the previous state in case of failure.

A special state is CPUHP_ONLINE_DYN. Its for dynamically registering a hotplug
callback pair. This is for drivers which have no dependencies to avoid that we
need to allocate CPUHP states for each of them

For both setup and remove helper functions are provided, which prevent the
core to issue the callbacks. This simplifies the conversion of existing
hotplug notifiers.

[ Dynamic registering implemented by Sebastian Siewior ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.103464877@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-01 20:36:55 +01:00

85 lines
2.5 KiB
C

#ifndef __CPUHOTPLUG_H
#define __CPUHOTPLUG_H
enum cpuhp_state {
CPUHP_OFFLINE,
CPUHP_CREATE_THREADS,
CPUHP_NOTIFY_PREPARE,
CPUHP_BRINGUP_CPU,
CPUHP_AP_OFFLINE,
CPUHP_AP_NOTIFY_STARTING,
CPUHP_AP_ONLINE,
CPUHP_TEARDOWN_CPU,
CPUHP_NOTIFY_ONLINE,
CPUHP_ONLINE_DYN,
CPUHP_ONLINE_DYN_END = CPUHP_ONLINE_DYN + 30,
CPUHP_ONLINE,
};
int __cpuhp_setup_state(enum cpuhp_state state, const char *name, bool invoke,
int (*startup)(unsigned int cpu),
int (*teardown)(unsigned int cpu));
/**
* cpuhp_setup_state - Setup hotplug state callbacks with calling the callbacks
* @state: The state for which the calls are installed
* @name: Name of the callback (will be used in debug output)
* @startup: startup callback function
* @teardown: teardown callback function
*
* Installs the callback functions and invokes the startup callback on
* the present cpus which have already reached the @state.
*/
static inline int cpuhp_setup_state(enum cpuhp_state state,
const char *name,
int (*startup)(unsigned int cpu),
int (*teardown)(unsigned int cpu))
{
return __cpuhp_setup_state(state, name, true, startup, teardown);
}
/**
* cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the
* callbacks
* @state: The state for which the calls are installed
* @name: Name of the callback.
* @startup: startup callback function
* @teardown: teardown callback function
*
* Same as @cpuhp_setup_state except that no calls are executed are invoked
* during installation of this callback. NOP if SMP=n or HOTPLUG_CPU=n.
*/
static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
const char *name,
int (*startup)(unsigned int cpu),
int (*teardown)(unsigned int cpu))
{
return __cpuhp_setup_state(state, name, false, startup, teardown);
}
void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
/**
* cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown
* @state: The state for which the calls are removed
*
* Removes the callback functions and invokes the teardown callback on
* the present cpus which have already reached the @state.
*/
static inline void cpuhp_remove_state(enum cpuhp_state state)
{
__cpuhp_remove_state(state, true);
}
/**
* cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking
* teardown
* @state: The state for which the calls are removed
*/
static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
{
__cpuhp_remove_state(state, false);
}
#endif