From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Andrew Morton <akpm@linux-foundation.org>,
Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Peter Anvin <hpa@zytor.com>, Oleg Nesterov <oleg@redhat.com>,
linux-arch@vger.kernel.org, Tejun Heo <tj@kernel.org>,
Steven Rostedt <rostedt@goodmis.org>,
Rusty Russell <rusty@rustcorp.com.au>,
Paul McKenney <paulmck@linux.vnet.ibm.com>,
Rafael Wysocki <rafael.j.wysocki@intel.com>,
Arjan van de Ven <arjan@linux.intel.com>,
Rik van Riel <riel@redhat.com>,
"Srivatsa S. Bhat" <srivatsa@mit.edu>,
Sebastian Siewior <bigeasy@linutronix.de>,
Paul Turner <pjt@google.com>
Subject: [patch 07/20] cpu/hotplug: Convert the hotplugged cpu work to a state machine
Date: Fri, 26 Feb 2016 18:43:29 -0000 [thread overview]
Message-ID: <20160226182340.770651526@linutronix.de> (raw)
In-Reply-To: 20160226164321.657646833@linutronix.de
[-- Attachment #1: cpu-hotplug-Convert-the-hotplugged-processor-work-to.patch --]
[-- Type: text/plain, Size: 5104 bytes --]
Move the functions which need to run on the hotplugged processor into
a state machine array and let the code iterate through these functions.
In a later state, this will grow synchronization points between the
control processor and the hotplugged processor, so we can move the
various architecture implementations of the synchronizations to the
core.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/cpuhotplug.h | 4 ++
kernel/cpu.c | 81 ++++++++++++++++++++++++++++++++++++---------
2 files changed, 70 insertions(+), 15 deletions(-)
Index: b/include/linux/cpuhotplug.h
===================================================================
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -6,6 +6,10 @@ enum cpuhp_state {
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,
};
Index: b/kernel/cpu.c
===================================================================
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -57,6 +57,7 @@ struct cpuhp_step {
};
static struct cpuhp_step cpuhp_bp_states[];
+static struct cpuhp_step cpuhp_ap_states[];
/**
* cpuhp_invoke_callback _ Invoke the callbacks for a given state
@@ -304,6 +305,12 @@ static int notify_online(unsigned int cp
return 0;
}
+static int notify_starting(unsigned int cpu)
+{
+ cpu_notify(CPU_STARTING, cpu);
+ return 0;
+}
+
static int bringup_cpu(unsigned int cpu)
{
struct task_struct *idle = idle_thread_get(cpu);
@@ -421,9 +428,17 @@ static int notify_down_prepare(unsigned
return err;
}
+static int notify_dying(unsigned int cpu)
+{
+ cpu_notify(CPU_DYING, cpu);
+ return 0;
+}
+
/* Take this CPU down. */
static int take_cpu_down(void *_param)
{
+ struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state);
+ enum cpuhp_state target = max((int)st->target, CPUHP_AP_OFFLINE);
int err, cpu = smp_processor_id();
/* Ensure this CPU doesn't handle any more interrupts. */
@@ -431,7 +446,12 @@ static int take_cpu_down(void *_param)
if (err < 0)
return err;
- cpu_notify(CPU_DYING, cpu);
+ /* Invoke the former CPU_DYING callbacks */
+ for (; st->state > target; st->state--) {
+ struct cpuhp_step *step = cpuhp_ap_states + st->state;
+
+ cpuhp_invoke_callback(cpu, st->state, step->teardown);
+ }
/* Give up timekeeping duties */
tick_handover_do_timer();
/* Park the stopper thread */
@@ -512,6 +532,7 @@ static int notify_dead(unsigned int cpu)
#define notify_down_prepare NULL
#define takedown_cpu NULL
#define notify_dead NULL
+#define notify_dying NULL
#endif
#ifdef CONFIG_HOTPLUG_CPU
@@ -615,6 +636,28 @@ void smpboot_thread_init(void)
register_cpu_notifier(&smpboot_thread_notifier);
}
+/**
+ * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers
+ * @cpu: cpu that just started
+ *
+ * This function calls the cpu_chain notifiers with CPU_STARTING.
+ * It must be called by the arch code on the new cpu, before the new cpu
+ * enables interrupts and before the "boot" cpu returns from __cpu_up().
+ */
+void notify_cpu_starting(unsigned int cpu)
+{
+ struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
+ enum cpuhp_state target = min((int)st->target, CPUHP_AP_ONLINE);
+
+ while (st->state < target) {
+ struct cpuhp_step *step;
+
+ st->state++;
+ step = cpuhp_ap_states + st->state;
+ cpuhp_invoke_callback(cpu, st->state, step->startup);
+ }
+}
+
static void undo_cpu_up(unsigned int cpu, struct cpuhp_cpu_state *st)
{
for (st->state--; st->state > st->target; st->state--) {
@@ -842,19 +885,6 @@ core_initcall(cpu_hotplug_pm_sync_init);
#endif /* CONFIG_PM_SLEEP_SMP */
-/**
- * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers
- * @cpu: cpu that just started
- *
- * This function calls the cpu_chain notifiers with CPU_STARTING.
- * It must be called by the arch code on the new cpu, before the new cpu
- * enables interrupts and before the "boot" cpu returns from __cpu_up().
- */
-void notify_cpu_starting(unsigned int cpu)
-{
- cpu_notify(CPU_STARTING, cpu);
-}
-
#endif /* CONFIG_SMP */
/* Boot processor state steps */
@@ -879,8 +909,12 @@ static struct cpuhp_step cpuhp_bp_states
[CPUHP_BRINGUP_CPU] = {
.name = "cpu:bringup",
.startup = bringup_cpu,
+ .teardown = NULL,
+ },
+ [CPUHP_TEARDOWN_CPU] = {
+ .name = "cpu:teardown",
+ .startup = NULL,
.teardown = takedown_cpu,
- .skip_onerr = true,
},
[CPUHP_NOTIFY_ONLINE] = {
.name = "notify:online",
@@ -889,6 +923,23 @@ static struct cpuhp_step cpuhp_bp_states
},
#endif
[CPUHP_ONLINE] = {
+ .name = "online",
+ .startup = NULL,
+ .teardown = NULL,
+ },
+};
+
+/* Application processor state steps */
+static struct cpuhp_step cpuhp_ap_states[] = {
+#ifdef CONFIG_SMP
+ [CPUHP_AP_NOTIFY_STARTING] = {
+ .name = "notify:starting",
+ .startup = notify_starting,
+ .teardown = notify_dying,
+ .skip_onerr = true,
+ },
+#endif
+ [CPUHP_ONLINE] = {
.name = "online",
.startup = NULL,
.teardown = NULL,
next prev parent reply other threads:[~2016-02-26 18:49 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-26 18:43 [patch 00/20] cpu/hotplug: Core infrastructure for cpu hotplug rework Thomas Gleixner
2016-02-26 18:43 ` [patch 01/20] idle: Move x86ism out of generic code Thomas Gleixner
2016-02-27 20:29 ` Brian Gerst
2016-02-29 19:35 ` Thomas Gleixner
2016-02-29 19:48 ` Will Deacon
2016-02-29 20:06 ` Thomas Gleixner
2016-02-26 18:43 ` [patch 02/20] cpu/hotplug: Restructure FROZEN state handling Thomas Gleixner
2016-03-01 19:51 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 22:35 ` Srivatsa S. Bhat
2016-03-02 23:43 ` Srivatsa S. Bhat
2016-02-26 18:43 ` [patch 03/20] cpu/hotplug: Restructure cpu_up code Thomas Gleixner
2016-03-01 19:52 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 22:36 ` Srivatsa S. Bhat
2016-02-26 18:43 ` [patch 04/20] cpu/hotplug: Split out cpu down functions Thomas Gleixner
2016-03-01 19:52 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 22:37 ` Srivatsa S. Bhat
2016-02-26 18:43 ` [patch 05/20] cpu/hotplug: Add tracepoints Thomas Gleixner
2016-03-01 19:52 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 06/20] cpu/hotplug: Convert to a state machine for the control processor Thomas Gleixner
2016-03-01 19:53 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 11:23 ` Peter Zijlstra
2016-02-26 18:43 ` Thomas Gleixner [this message]
2016-03-01 19:53 ` [tip:smp/hotplug] cpu/hotplug: Convert the hotplugged cpu work to a state machine tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 08/20] cpu/hotplug: Hand in target state to _cpu_up/down Thomas Gleixner
2016-03-01 19:54 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 09/20] cpu/hotplug: Add sysfs state interface Thomas Gleixner
2016-03-01 19:54 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 12:40 ` Peter Zijlstra
2016-02-26 18:43 ` [patch 10/20] cpu/hotplug: Make target state writeable Thomas Gleixner
2016-02-26 23:46 ` Rafael J. Wysocki
2016-02-27 7:39 ` Thomas Gleixner
2016-02-27 14:43 ` Rafael J. Wysocki
2016-02-28 14:49 ` Thomas Gleixner
2016-02-29 15:49 ` Thomas Gleixner
2016-03-01 1:53 ` Rafael J. Wysocki
2016-03-01 19:55 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 12:41 ` Peter Zijlstra
2016-03-02 19:57 ` Thomas Gleixner
2016-02-26 18:43 ` [patch 11/20] cpu/hotplug: Implement setup/removal interface Thomas Gleixner
2016-03-01 19:55 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 12/20] cpu/hotplug: Move scheduler cpu_online notifier to hotplug core Thomas Gleixner
2016-03-01 19:55 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 13/20] cpu/hotplug: Unpark smpboot threads from the state machine Thomas Gleixner
2016-03-01 19:56 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 14/20] cpu/hotplug: Split out the state walk into functions Thomas Gleixner
2016-03-01 19:56 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 15/20] cpu/hotplug: Create hotplug threads Thomas Gleixner
2016-03-01 19:57 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 16/20] cpu/hotplug: Move online calls to hotplugged cpu Thomas Gleixner
2016-03-01 19:57 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 17/20] arch/hotplug: Call into idle with a proper state Thomas Gleixner
2016-03-01 19:57 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 18/20] cpu/hotplug: Let upcoming cpu bring itself fully up Thomas Gleixner
2016-03-01 19:58 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 17:28 ` [patch 18/20] " Richard Cochran
2016-02-26 18:43 ` [patch 19/20] cpu/hotplug: Make wait for dead cpu completion based Thomas Gleixner
2016-03-01 19:58 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-02-26 18:43 ` [patch 20/20] rcu: Make CPU_DYING_IDLE an explicit call Thomas Gleixner
2016-02-27 2:14 ` Paul E. McKenney
2016-02-27 2:23 ` Paul E. McKenney
2016-02-27 7:47 ` Thomas Gleixner
2016-02-27 11:05 ` Paul E. McKenney
2016-02-27 11:30 ` Thomas Gleixner
2016-02-27 16:33 ` Paul E. McKenney
2016-03-01 19:58 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2016-03-02 20:11 ` Paul E. McKenney
2016-03-03 7:31 ` Thomas Gleixner
2016-03-03 10:03 ` [tip:smp/hotplug] cpu/hotplug: Plug death reporting race tip-bot for Thomas Gleixner
2016-03-03 14:11 ` Paul E. McKenney
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160226182340.770651526@linutronix.de \
--to=tglx@linutronix.de \
--cc=akpm@linux-foundation.org \
--cc=arjan@linux.intel.com \
--cc=bigeasy@linutronix.de \
--cc=hpa@zytor.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=oleg@redhat.com \
--cc=paulmck@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=rafael.j.wysocki@intel.com \
--cc=riel@redhat.com \
--cc=rostedt@goodmis.org \
--cc=rusty@rustcorp.com.au \
--cc=srivatsa@mit.edu \
--cc=tj@kernel.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).