From 7863406143d8bbbbda07a61285c5f4c217908dfd Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <frederic@kernel.org>
Date: Fri, 27 Oct 2017 04:42:28 +0200
Subject: sched/isolation: Move housekeeping related code to its own file

The housekeeping code is currently tied to the NOHZ code. As we are
planning to make housekeeping independent from it, start with moving
the relevant code to its own file.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1509072159-31808-2-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/Makefile    |  1 +
 kernel/sched/core.c      |  1 +
 kernel/sched/fair.c      |  1 +
 kernel/sched/isolation.c | 33 +++++++++++++++++++++++++++++++++
 4 files changed, 36 insertions(+)
 create mode 100644 kernel/sched/isolation.c

(limited to 'kernel/sched')

diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 78f54932ea1d..871d43d73375 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -26,3 +26,4 @@ obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o
 obj-$(CONFIG_CPU_FREQ) += cpufreq.o
 obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o
 obj-$(CONFIG_MEMBARRIER) += membarrier.o
+obj-$(CONFIG_NO_HZ_FULL) += isolation.o
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2288a145bf01..ad188acb7636 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -26,6 +26,7 @@
 #include <linux/profile.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
+#include <linux/sched/isolation.h>
 
 #include <asm/switch_to.h>
 #include <asm/tlb.h>
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 56f343b8e749..591481db8c6a 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -32,6 +32,7 @@
 #include <linux/mempolicy.h>
 #include <linux/migrate.h>
 #include <linux/task_work.h>
+#include <linux/sched/isolation.h>
 
 #include <trace/events/sched.h>
 
diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
new file mode 100644
index 000000000000..3589252ed476
--- /dev/null
+++ b/kernel/sched/isolation.c
@@ -0,0 +1,33 @@
+/*
+ *  Housekeeping management. Manage the targets for routine code that can run on
+ *  any CPU: unbound workqueues, timers, kthreads and any offloadable work.
+ *
+ * Copyright (C) 2017 Red Hat, Inc., Frederic Weisbecker
+ *
+ */
+
+#include <linux/sched/isolation.h>
+#include <linux/tick.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+
+cpumask_var_t housekeeping_mask;
+
+void __init housekeeping_init(void)
+{
+	if (!tick_nohz_full_enabled())
+		return;
+
+	if (!alloc_cpumask_var(&housekeeping_mask, GFP_KERNEL)) {
+		WARN(1, "NO_HZ: Can't allocate not-full dynticks cpumask\n");
+		cpumask_clear(tick_nohz_full_mask);
+		tick_nohz_full_running = false;
+		return;
+	}
+
+	cpumask_andnot(housekeeping_mask,
+		       cpu_possible_mask, tick_nohz_full_mask);
+
+	/* We need at least one CPU to handle housekeeping work */
+	WARN_ON_ONCE(cpumask_empty(housekeeping_mask));
+}
-- 
cgit