From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752673AbcCJMGI (ORCPT ); Thu, 10 Mar 2016 07:06:08 -0500 Received: from www.linutronix.de ([62.245.132.108]:60754 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752142AbcCJMGA (ORCPT ); Thu, 10 Mar 2016 07:06:00 -0500 Message-Id: <20160310120024.579605542@linutronix.de> User-Agent: quilt/0.63-1 Date: Thu, 10 Mar 2016 12:04:36 -0000 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , rt@linutronix.de Subject: [patch 01/15] cpu/hotplug: Document states better References: <20160310115406.940706476@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=cpu-hotplug--Document-states-better.patch X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Requested-by: Peter Zijlstra Signed-off-by: Thomas Gleixner --- kernel/cpu.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 46 insertions(+), 1 deletion(-) --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1171,6 +1171,10 @@ static struct cpuhp_step cpuhp_bp_states .teardown = NULL, .cant_stop = true, }, + /* + * Preparatory and dead notifiers. Will be replaced once the notifiers + * are converted to states. + */ [CPUHP_NOTIFY_PREPARE] = { .name = "notify:prepare", .startup = notify_prepare, @@ -1178,12 +1182,17 @@ static struct cpuhp_step cpuhp_bp_states .skip_onerr = true, .cant_stop = true, }, + /* Kicks the plugged cpu into life */ [CPUHP_BRINGUP_CPU] = { .name = "cpu:bringup", .startup = bringup_cpu, .teardown = NULL, .cant_stop = true, }, + /* + * Handled on controll processor until the plugged processor manages + * this itself. + */ [CPUHP_TEARDOWN_CPU] = { .name = "cpu:teardown", .startup = NULL, @@ -1196,6 +1205,23 @@ static struct cpuhp_step cpuhp_bp_states /* Application processor state steps */ static struct cpuhp_step cpuhp_ap_states[] = { #ifdef CONFIG_SMP + /* Final state before CPU kills itself */ + [CPUHP_AP_IDLE_DEAD] = { + .name = "idle:dead", + }, + /* + * Last state before CPU enters the idle loop to die. Transient state + * for synchronization. + */ + [CPUHP_AP_OFFLINE] = { + .name = "ap:offline", + .cant_stop = true, + }, + /* + * Low level startup/teardown notifiers. Run with interrupts + * disabled. Will be removed once the notifiers are converted to + * states. + */ [CPUHP_AP_NOTIFY_STARTING] = { .name = "notify:starting", .startup = notify_starting, @@ -1203,17 +1229,32 @@ static struct cpuhp_step cpuhp_ap_states .skip_onerr = true, .cant_stop = true, }, + /* Entry state on starting. Interrupts enabled from here on. Transient + * state for synchronsization */ + [CPUHP_AP_ONLINE] = { + .name = "ap:online", + }, + /* Handle smpboot threads park/unpark */ [CPUHP_AP_SMPBOOT_THREADS] = { .name = "smpboot:threads", .startup = smpboot_unpark_threads, .teardown = smpboot_park_threads, }, + /* + * Online/down_prepare notifiers. Will be removed once the notifiers + * are converted to states. + */ [CPUHP_AP_NOTIFY_ONLINE] = { .name = "notify:online", .startup = notify_online, .teardown = notify_down_prepare, }, #endif + /* + * The dynamically registered state space is here + */ + + /* CPU is fully up and running. */ [CPUHP_ONLINE] = { .name = "online", .startup = NULL, @@ -1231,7 +1272,11 @@ static int cpuhp_cb_check(enum cpuhp_sta static bool cpuhp_is_ap_state(enum cpuhp_state state) { - return state > CPUHP_BRINGUP_CPU; + /* + * The extra check for CPUHP_TEARDOWN_CPU is only for documentation + * purposes as that state is handled explicitely in cpu_down. + */ + return state > CPUHP_BRINGUP_CPU && state != CPUHP_TEARDOWN_CPU; } static struct cpuhp_step *cpuhp_get_step(enum cpuhp_state state)