| Date | Thu, 20 Apr 2017 04:24:58 -0700 | From | tip-bot for Sebastian Andrzej Siewior <> | Subject | [tip:smp/hotplug] powerpc/powernv: Use stop_machine_cpuslocked() |
| |
Commit-ID: 6e9e61778f976b52fbdeb315850ee6eb4695a1e5 Gitweb: http://git.kernel.org/tip/6e9e61778f976b52fbdeb315850ee6eb4695a1e5 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> AuthorDate: Tue, 18 Apr 2017 19:04:55 +0200 Committer: Thomas Gleixner <tglx@linutronix.de> CommitDate: Thu, 20 Apr 2017 13:08:54 +0200
powerpc/powernv: Use stop_machine_cpuslocked()
set_subcores_per_core() holds get_online_cpus() while invoking stop_machine().
stop_machine() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem.
Use stop_machine_cpuslocked() to avoid the nested call.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20170418170553.447314339@linutronix.de
--- arch/powerpc/platforms/powernv/subcore.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/platforms/powernv/subcore.c b/arch/powerpc/platforms/powernv/subcore.c index 0babef1..67cbf45 100644 --- a/arch/powerpc/platforms/powernv/subcore.c +++ b/arch/powerpc/platforms/powernv/subcore.c @@ -356,7 +356,8 @@ static int set_subcores_per_core(int new_mode) /* Ensure state is consistent before we call the other cpus */ mb(); - stop_machine(cpu_update_split_mode, &new_mode, cpu_online_mask); + stop_machine_cpuslocked(cpu_update_split_mode, &new_mode, + cpu_online_mask); put_online_cpus();
|