[PATCH 3/8] x86, mce: introduce mce_timer_add()

[Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>]

It is too redundant to call setup_timer() every time when the timer is
going to be added.

This patch breaks __mcheck_cpu_init_timer() down, put setup part to init
code path and construct mce_timer_add() from the rests. Since there is no
strong reason to keep interval only when it back from hotplug event, this
patch also helps to kill duplicated code in hotplug notifier.

As the sideline this patch includes rename of mce_start_timer() to
mce_timer_run(), to group related functions with mce_timer_ prefix.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
---
 arch/x86/kernel/cpu/mcheck/mce.c |   54 ++++++++++++++++++-------------------
 1 files changed, 26 insertions(+), 28 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 205b334..c3dad64 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1114,7 +1114,7 @@ static int check_interval = 5 * 60; /* 5 minutes */
 static DEFINE_PER_CPU(int, mce_next_interval); /* in jiffies */
 static DEFINE_PER_CPU(struct timer_list, mce_timer);
 
-static void mce_start_timer(unsigned long data)
+static void mce_timer_run(unsigned long data)
 {
 	struct timer_list *t = &per_cpu(mce_timer, data);
 	int *n;
@@ -1147,6 +1147,21 @@ static void mce_timer_delete_all(void)
 	}
 }
 
+static void mce_timer_add(unsigned long cpu)
+{
+	struct timer_list *t = &per_cpu(mce_timer, cpu);
+	int *n = &per_cpu(mce_next_interval, cpu);
+
+	if (mce_ignore_ce || !check_interval)
+		return;
+
+	/* reset next interval */
+	*n = check_interval * HZ;
+
+	t->expires = round_jiffies(jiffies + *n);
+	add_timer_on(t, cpu);
+}
+
 static void mce_do_trigger(struct work_struct *work)
 {
 	call_usermodehelper(mce_helper, mce_helper_argv, NULL, UMH_NO_WAIT);
@@ -1374,23 +1389,6 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
 	}
 }
 
-static void __mcheck_cpu_init_timer(void)
-{
-	struct timer_list *t = &__get_cpu_var(mce_timer);
-	int *n = &__get_cpu_var(mce_next_interval);
-
-	setup_timer(t, mce_start_timer, smp_processor_id());
-
-	if (mce_ignore_ce)
-		return;
-
-	*n = check_interval * HZ;
-	if (!*n)
-		return;
-	t->expires = round_jiffies(jiffies + *n);
-	add_timer_on(t, smp_processor_id());
-}
-
 /* Handle unconfigured int18 (should never happen) */
 static void unexpected_machine_check(struct pt_regs *regs, long error_code)
 {
@@ -1408,6 +1406,8 @@ void (*machine_check_vector)(struct pt_regs *, long error_code) =
  */
 void __cpuinit mcheck_cpu_init(struct cpuinfo_x86 *c)
 {
+	int cpu = smp_processor_id();
+
 	if (mce_disabled)
 		return;
 
@@ -1433,9 +1433,12 @@ void __cpuinit mcheck_cpu_init(struct cpuinfo_x86 *c)
 
 	__mcheck_cpu_init_generic();
 	__mcheck_cpu_init_vendor(c);
-	__mcheck_cpu_init_timer();
+
+	setup_timer(&__get_cpu_var(mce_timer), mce_timer_run, cpu);
 	INIT_WORK(&__get_cpu_var(mce_work), mce_process_work);
 	init_irq_work(&__get_cpu_var(mce_irq_work), &mce_irq_work_cb);
+
+	mce_timer_add(cpu);
 }
 
 /*
@@ -1765,7 +1768,7 @@ static struct syscore_ops mce_syscore_ops = {
 static void mce_cpu_restart(void *data)
 {
 	__mcheck_cpu_init_generic();
-	__mcheck_cpu_init_timer();
+	mce_timer_add(smp_processor_id());
 }
 
 /* Reinit MCEs after user configuration changes */
@@ -1786,7 +1789,7 @@ static void mce_enable_ce(void *all)
 	cmci_reenable();
 	cmci_recheck();
 	if (all)
-		__mcheck_cpu_init_timer();
+		mce_timer_add(smp_processor_id());
 }
 
 static struct sysdev_class mce_sysdev_class = {
@@ -2030,7 +2033,6 @@ static int __cpuinit
 mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (unsigned long)hcpu;
-	struct timer_list *t = &per_cpu(mce_timer, cpu);
 
 	switch (action) {
 	case CPU_ONLINE:
@@ -2047,16 +2049,12 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		break;
 	case CPU_DOWN_PREPARE:
 	case CPU_DOWN_PREPARE_FROZEN:
-		del_timer_sync(t);
+		del_timer_sync(&per_cpu(mce_timer, cpu));
 		smp_call_function_single(cpu, mce_disable_cpu, &action, 1);
 		break;
 	case CPU_DOWN_FAILED:
 	case CPU_DOWN_FAILED_FROZEN:
-		if (!mce_ignore_ce && check_interval) {
-			t->expires = round_jiffies(jiffies +
-					   __get_cpu_var(mce_next_interval));
-			add_timer_on(t, cpu);
-		}
+		mce_timer_add(cpu);
 		smp_call_function_single(cpu, mce_reenable_cpu, &action, 1);
 		break;
 	case CPU_POST_DEAD:
-- 
1.7.1