cpu/hotplug: Provide cpuhp_setup/remove_state[_nocalls]_cpuslocked()
authorSebastian Andrzej Siewior <bigeasy@linutronix.de>
Wed, 24 May 2017 08:15:14 +0000 (10:15 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Fri, 26 May 2017 08:10:35 +0000 (10:10 +0200)
commit71def423fe3da0d40ad3427a4cd5f9edc53bff67
tree71a4e6c37a8972226dcf828474b8090d355a727f
parentade3f680a76b474d9f5375a9b1d100ee787bf469
cpu/hotplug: Provide cpuhp_setup/remove_state[_nocalls]_cpuslocked()

Some call sites of cpuhp_setup/remove_state[_nocalls]() are within a
cpus_read locked region.

cpuhp_setup/remove_state[_nocalls]() call cpus_read_lock() as well, which
is possible in the current implementation but prevents converting the
hotplug locking to a percpu rwsem.

Provide locked versions of the interfaces to avoid nested calls to
cpus_read_lock().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170524081547.239600868@linutronix.de
include/linux/cpuhotplug.h
kernel/cpu.c