[PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Eduard - Gabriel Munteanu]

A previous patch added the early_initcall(), to allow a cleaner hooking of
pre-SMP initcalls. Now we remove the older interface, converting all
existing users to the new one.

Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
---
 include/linux/sched.h |    9 ---------
 init/main.c           |   22 +---------------------
 kernel/sched.c        |    6 +++++-
 kernel/softirq.c      |    4 +++-
 kernel/softlockup.c   |   27 ++++++++++++++++++++++++---
 5 files changed, 33 insertions(+), 35 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index c5d3f84..efd8877 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -291,7 +291,6 @@ extern void sched_show_task(struct task_struct *p);
 
 #ifdef CONFIG_DETECT_SOFTLOCKUP
 extern void softlockup_tick(void);
-extern void spawn_softlockup_task(void);
 extern void touch_softlockup_watchdog(void);
 extern void touch_all_softlockup_watchdogs(void);
 extern unsigned long  softlockup_thresh;
@@ -2200,14 +2199,6 @@ static inline void inc_syscw(struct task_struct *tsk)
 }
 #endif
 
-#ifdef CONFIG_SMP
-void migration_init(void);
-#else
-static inline void migration_init(void)
-{
-}
-#endif
-
 #ifndef TASK_SIZE_OF
 #define TASK_SIZE_OF(tsk)	TASK_SIZE
 #endif
diff --git a/init/main.c b/init/main.c
index c5397f6..057f364 100644
--- a/init/main.c
+++ b/init/main.c
@@ -766,16 +766,7 @@ static void __init do_basic_setup(void)
 	do_initcalls();
 }
 
-static int __initdata nosoftlockup;
-
-static int __init nosoftlockup_setup(char *str)
-{
-	nosoftlockup = 1;
-	return 1;
-}
-__setup("nosoftlockup", nosoftlockup_setup);
-
-static void __init __do_pre_smp_initcalls(void)
+static void __init do_pre_smp_initcalls(void)
 {
 	initcall_t *call;
 
@@ -783,16 +774,6 @@ static void __init __do_pre_smp_initcalls(void)
 		do_one_initcall(*call);
 }
 
-static void __init do_pre_smp_initcalls(void)
-{
-	extern int spawn_ksoftirqd(void);
-
-	migration_init();
-	spawn_ksoftirqd();
-	if (!nosoftlockup)
-		spawn_softlockup_task();
-}
-
 static void run_init_process(char *init_filename)
 {
 	argv_init[0] = init_filename;
@@ -864,7 +845,6 @@ static int __init kernel_init(void * unused)
 
 	smp_prepare_cpus(setup_max_cpus);
 
-	__do_pre_smp_initcalls();
 	do_pre_smp_initcalls();
 
 	smp_init();
diff --git a/kernel/sched.c b/kernel/sched.c
index b048ad8..ccddfdd 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6175,7 +6175,7 @@ static struct notifier_block __cpuinitdata migration_notifier = {
 	.priority = 10
 };
 
-void __init migration_init(void)
+static int __init migration_init(void)
 {
 	void *cpu = (void *)(long)smp_processor_id();
 	int err;
@@ -6185,7 +6185,11 @@ void __init migration_init(void)
 	BUG_ON(err == NOTIFY_BAD);
 	migration_call(&migration_notifier, CPU_ONLINE, cpu);
 	register_cpu_notifier(&migration_notifier);
+
+	return err;
 }
+
+early_initcall(migration_init);
 #endif
 
 #ifdef CONFIG_SMP
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 36e0617..2ef08c7 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -659,7 +659,7 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
 	.notifier_call = cpu_callback
 };
 
-__init int spawn_ksoftirqd(void)
+static __init int spawn_ksoftirqd(void)
 {
 	void *cpu = (void *)(long)smp_processor_id();
 	int err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
@@ -670,6 +670,8 @@ __init int spawn_ksoftirqd(void)
 	return 0;
 }
 
+early_initcall(spawn_ksoftirqd);
+
 #ifdef CONFIG_SMP
 /*
  * Call a function on all processors
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index c828c23..1653802 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -306,14 +306,35 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
 	.notifier_call = cpu_callback
 };
 
-__init void spawn_softlockup_task(void)
+static int __initdata nosoftlockup;
+
+static int __init nosoftlockup_setup(char *str)
+{
+	nosoftlockup = 1;
+	return 1;
+}
+__setup("nosoftlockup", nosoftlockup_setup);
+
+static int __init spawn_softlockup_task(void)
 {
 	void *cpu = (void *)(long)smp_processor_id();
-	int err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
+	int err;
+
+	if (nosoftlockup)
+		return 0;
 
-	BUG_ON(err == NOTIFY_BAD);
+	err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
+	if (err == NOTIFY_BAD) {
+		BUG();
+		return 1;
+	}
 	cpu_callback(&cpu_nfb, CPU_ONLINE, cpu);
 	register_cpu_notifier(&cpu_nfb);
 
 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
+
+	return 0;
 }
+
+early_initcall(spawn_softlockup_task);
+
-- 
1.5.5.4

Re: [PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Andrew Morton]

On Mon, 23 Jun 2008 15:30:56 +0300
Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> wrote:

> A previous patch added the early_initcall(), to allow a cleaner hooking of
> pre-SMP initcalls. Now we remove the older interface, converting all
> existing users to the new one.

The patch failed to convert init_call_single_data() because you're
working against a two-month-old codebase.  Patches against linux-next
are more appropriate, particularly late in -rc.

Please check that what I committed actually worked, thanks.

[PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Eduard - Gabriel Munteanu]

A previous patch added the early_initcall(), to allow a cleaner hooking of
pre-SMP initcalls. Now we remove the older interface, converting all
existing users to the new one.

Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
---
 include/linux/sched.h |   12 ------------
 include/linux/smp.h   |    8 --------
 init/main.c           |   23 +----------------------
 kernel/sched.c        |    6 +++++-
 kernel/smp.c          |    6 +++++-
 kernel/softirq.c      |    4 +++-
 kernel/softlockup.c   |   27 ++++++++++++++++++++++++---
 7 files changed, 38 insertions(+), 48 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 239df23..495996d 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -292,7 +292,6 @@ extern void sched_show_task(struct task_struct *p);
 
 #ifdef CONFIG_DETECT_SOFTLOCKUP
 extern void softlockup_tick(void);
-extern void spawn_softlockup_task(void);
 extern void touch_softlockup_watchdog(void);
 extern void touch_all_softlockup_watchdogs(void);
 extern unsigned int  softlockup_panic;
@@ -304,9 +303,6 @@ extern int softlockup_thresh;
 static inline void softlockup_tick(void)
 {
 }
-static inline void spawn_softlockup_task(void)
-{
-}
 static inline void touch_softlockup_watchdog(void)
 {
 }
@@ -2211,14 +2207,6 @@ static inline void inc_syscw(struct task_struct *tsk)
 }
 #endif
 
-#ifdef CONFIG_SMP
-void migration_init(void);
-#else
-static inline void migration_init(void)
-{
-}
-#endif
-
 #ifndef TASK_SIZE_OF
 #define TASK_SIZE_OF(tsk)	TASK_SIZE
 #endif
diff --git a/include/linux/smp.h b/include/linux/smp.h
index 4d4c6ad..3c26b21 100644
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -75,12 +75,7 @@ void __smp_call_function_single(int cpuid, struct call_single_data *data);
 #ifdef CONFIG_USE_GENERIC_SMP_HELPERS
 void generic_smp_call_function_single_interrupt(void);
 void generic_smp_call_function_interrupt(void);
-void init_call_single_data(void);
 extern spinlock_t call_function_lock;
-#else
-static inline void init_call_single_data(void)
-{
-}
 #endif
 
 /*
@@ -138,9 +133,6 @@ static inline void smp_send_reschedule(int cpu) { }
 })
 #define smp_call_function_mask(mask, func, info, wait) \
 			(up_smp_call_function(func, info))
-static inline void init_call_single_data(void)
-{
-}
 #endif /* !SMP */
 
 /*
diff --git a/init/main.c b/init/main.c
index 9e34d92..bfbfadd 100644
--- a/init/main.c
+++ b/init/main.c
@@ -776,16 +776,7 @@ static void __init do_basic_setup(void)
 	do_initcalls();
 }
 
-static int __initdata nosoftlockup;
-
-static int __init nosoftlockup_setup(char *str)
-{
-	nosoftlockup = 1;
-	return 1;
-}
-__setup("nosoftlockup", nosoftlockup_setup);
-
-static void __init __do_pre_smp_initcalls(void)
+static void __init do_pre_smp_initcalls(void)
 {
 	initcall_t *call;
 
@@ -793,17 +784,6 @@ static void __init __do_pre_smp_initcalls(void)
 		do_one_initcall(*call);
 }
 
-static void __init do_pre_smp_initcalls(void)
-{
-	extern int spawn_ksoftirqd(void);
-
-	init_call_single_data();
-	migration_init();
-	spawn_ksoftirqd();
-	if (!nosoftlockup)
-		spawn_softlockup_task();
-}
-
 static void run_init_process(char *init_filename)
 {
 	argv_init[0] = init_filename;
@@ -884,7 +864,6 @@ static int __init kernel_init(void * unused)
 
 	smp_prepare_cpus(setup_max_cpus);
 
-	__do_pre_smp_initcalls();
 	do_pre_smp_initcalls();
 
 	smp_init();
diff --git a/kernel/sched.c b/kernel/sched.c
index 306f7f6..3c987f3 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6244,7 +6244,7 @@ static struct notifier_block __cpuinitdata migration_notifier = {
 	.priority = 10
 };
 
-void __init migration_init(void)
+static int __init migration_init(void)
 {
 	void *cpu = (void *)(long)smp_processor_id();
 	int err;
@@ -6254,7 +6254,11 @@ void __init migration_init(void)
 	BUG_ON(err == NOTIFY_BAD);
 	migration_call(&migration_notifier, CPU_ONLINE, cpu);
 	register_cpu_notifier(&migration_notifier);
+
+	return err;
 }
+
+early_initcall(migration_init);
 #endif
 
 #ifdef CONFIG_SMP
diff --git a/kernel/smp.c b/kernel/smp.c
index a0c9cb0..f121e1d 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -33,7 +33,7 @@ struct call_single_queue {
 	spinlock_t lock;
 };
 
-void __cpuinit init_call_single_data(void)
+static int __cpuinit init_call_single_data(void)
 {
 	int i;
 
@@ -43,8 +43,12 @@ void __cpuinit init_call_single_data(void)
 		spin_lock_init(&q->lock);
 		INIT_LIST_HEAD(&q->list);
 	}
+
+	return 0;
 }
 
+early_initcall(init_call_single_data);
+
 static void csd_flag_wait(struct call_single_data *data)
 {
 	/* Wait for response */
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 0592568..efab66a 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -658,7 +658,7 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
 	.notifier_call = cpu_callback
 };
 
-__init int spawn_ksoftirqd(void)
+static int __init spawn_ksoftirqd(void)
 {
 	void *cpu = (void *)(long)smp_processor_id();
 	int err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
@@ -669,6 +669,8 @@ __init int spawn_ksoftirqd(void)
 	return 0;
 }
 
+early_initcall(spawn_ksoftirqd);
+
 #ifdef CONFIG_SMP
 /*
  * Call a function on all processors
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 6b682d8..393d310 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -335,14 +335,35 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
 	.notifier_call = cpu_callback
 };
 
-__init void spawn_softlockup_task(void)
+static int __initdata nosoftlockup;
+
+static int __init nosoftlockup_setup(char *str)
+{
+	nosoftlockup = 1;
+	return 1;
+}
+__setup("nosoftlockup", nosoftlockup_setup);
+
+static int __init spawn_softlockup_task(void)
 {
 	void *cpu = (void *)(long)smp_processor_id();
-	int err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
+	int err;
+
+	if (nosoftlockup)
+		return 0;
 
-	BUG_ON(err == NOTIFY_BAD);
+	err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
+	if (err == NOTIFY_BAD) {
+		BUG();
+		return 1;
+	}
 	cpu_callback(&cpu_nfb, CPU_ONLINE, cpu);
 	register_cpu_notifier(&cpu_nfb);
 
 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
+
+	return 0;
 }
+
+early_initcall(spawn_softlockup_task);
+
-- 
1.5.5.4

Re: [PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Eduard - Gabriel Munteanu]

Hi,

Please merge this instead, it's based on linux-next. Your change wasn't
enough.

And I don't think Tom Zanussi should be Cc-ed on patches 1 and 2, these
are mere prereqs for the 3rd. So add the Cc for Tom just for the third.
You could add yourself as Cc to the other two, or whoever you think is
responsible for such core stuff.


	Cheers,
	Eduard

Re: [PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Johannes Weiner]

Hi Eduard,

Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> writes:

> A previous patch added the early_initcall(), to allow a cleaner hooking of
> pre-SMP initcalls. Now we remove the older interface, converting all
> existing users to the new one.
>
> Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
> ---
>  include/linux/sched.h |   12 ------------
>  include/linux/smp.h   |    8 --------
>  init/main.c           |   23 +----------------------
>  kernel/sched.c        |    6 +++++-
>  kernel/smp.c          |    6 +++++-
>  kernel/softirq.c      |    4 +++-
>  kernel/softlockup.c   |   27 ++++++++++++++++++++++++---
>  7 files changed, 38 insertions(+), 48 deletions(-)
...
> diff --git a/kernel/softirq.c b/kernel/softirq.c
> index 0592568..efab66a 100644
> --- a/kernel/softirq.c
> +++ b/kernel/softirq.c
> @@ -658,7 +658,7 @@ static struct notifier_block __cpuinitdata cpu_nfb = {
>  	.notifier_call = cpu_callback
>  };
>  
> -__init int spawn_ksoftirqd(void)
> +static int __init spawn_ksoftirqd(void)
>  {
>  	void *cpu = (void *)(long)smp_processor_id();
>  	int err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu);
> @@ -669,6 +669,8 @@ __init int spawn_ksoftirqd(void)
>  	return 0;
>  }

You forgot to remove the declaration from linux/interrupt.h.

Andrew, the following fix is needed for -mmotm:

From: Johannes Weiner <hannes@saeurebad.de>
Subject: full-conversion-to-early_initcall-interface-remove-old-interface-fix

Original patch made spawn_softirqd() static but failed to remove the
global definition.  Do so now.

Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
---

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 30da779..62aa4f8 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -299,7 +299,6 @@ extern void softirq_init(void);
 #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)
 extern void raise_softirq_irqoff(unsigned int nr);
 extern void raise_softirq(unsigned int nr);
-extern int spawn_ksoftirqd(void);
 
 
 /* Tasklets --- multithreaded analogue of BHs.

Re: [PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Eduard - Gabriel Munteanu]

On Fri, 27 Jun 2008 12:54:21 +0200
Johannes Weiner <hannes@saeurebad.de> wrote:

> Hi Eduard,

Hi.
 
> You forgot to remove the declaration from linux/interrupt.h.

The last patch was made against linux-next, as Andrew Morton
suggested, where spawn_ksoftirqd() was declared in the scope of
__do_pre_smp_initcall():
@@ -793,17 +784,6 @@ static void __init __do_pre_smp_initcalls(void)
 		do_one_initcall(*call);
 }
 
-static void __init do_pre_smp_initcalls(void)
-{
-	extern int spawn_ksoftirqd(void);
-
-	init_call_single_data();
-	migration_init();
-	spawn_ksoftirqd();
-	if (!nosoftlockup)
-		spawn_softlockup_task();
-}
-

It may be that some other patch in -mmotm moves that into
include/linux/interrupt.h. In linux-next with my patch, running
$ find . -name \*.h | xargs grep "spawn_ksoftirqd"
shows nothing.

Thanks for spotting this difference.

(Using -mmotm + quilt myself is an additional headache, since git
already does what I want in terms of patch (read commits) management;
that's why I prefered linux-next.)

> Andrew, the following fix is needed for -mmotm:
> 
> From: Johannes Weiner <hannes@saeurebad.de>
> Subject:
> full-conversion-to-early_initcall-interface-remove-old-interface-fix
> 
> Original patch made spawn_softirqd() static but failed to remove the
> global definition.  Do so now.
> 
> Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
> ---
> 
> diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
> index 30da779..62aa4f8 100644
> --- a/include/linux/interrupt.h
> +++ b/include/linux/interrupt.h
> @@ -299,7 +299,6 @@ extern void softirq_init(void);
>  #define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL <<
> (nr)); } while (0) extern void raise_softirq_irqoff(unsigned int nr);
>  extern void raise_softirq(unsigned int nr);
> -extern int spawn_ksoftirqd(void);
>  
>  
>  /* Tasklets --- multithreaded analogue of BHs.


	Cheers,
	Eduard

Re: [PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Andrew Morton]

On Fri, 27 Jun 2008 14:28:00 +0300
Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> wrote:

> On Fri, 27 Jun 2008 12:54:21 +0200
> Johannes Weiner <hannes@saeurebad.de> wrote:
> 
> > Hi Eduard,
> 
> Hi.
>  
> > You forgot to remove the declaration from linux/interrupt.h.
> 
> The last patch was made against linux-next, as Andrew Morton
> suggested, where spawn_ksoftirqd() was declared in the scope of
> __do_pre_smp_initcall():
> @@ -793,17 +784,6 @@ static void __init __do_pre_smp_initcalls(void)
>  		do_one_initcall(*call);
>  }
>  
> -static void __init do_pre_smp_initcalls(void)
> -{
> -	extern int spawn_ksoftirqd(void);
> -
> -	init_call_single_data();
> -	migration_init();
> -	spawn_ksoftirqd();
> -	if (!nosoftlockup)
> -		spawn_softlockup_task();
> -}
> -
> 
> It may be that some other patch in -mmotm moves that into
> include/linux/interrupt.h. In linux-next with my patch, running
> $ find . -name \*.h | xargs grep "spawn_ksoftirqd"
> shows nothing.

Yes, I dropped that patch as it's no longer relevant.

> Thanks for spotting this difference.
> 
> (Using -mmotm + quilt myself is an additional headache, since git
> already does what I want in terms of patch (read commits) management;
> that's why I prefered linux-next.)

It is a bit of a pain.  I avoid asking people to raise patches against
-mm unless it's really necessary.

Re: [PATCH 2/3] Full conversion to early_initcall() interface, remove old interface.

[Eduard - Gabriel Munteanu]

On Fri, 27 Jun 2008 11:45:15 -0700
Andrew Morton <akpm@linux-foundation.org> wrote:

> It is a bit of a pain.  I avoid asking people to raise patches against
> -mm unless it's really necessary.

Just my 2 cents... you said in a 2006 discussion that you don't use Git
because you modify and drop patches often. I'd like to point out that
newer Git releases support interactive rebasing, which can do very nice
things:
- reorder commits (also adds '<<<', '===', '>>>' merge-like stuff when
that fails, so you can fix it easier)
- squash a commit into the previous -> solves the "patch that fixes
another patch" problem.
- edit commits different than HEAD
That is all doable with 'git-rebase -i'.

But maybe you got used to quilt and changing requires more effort at
the beginning, so I'm not going to argue too much.

I hope this helps.


	Cheers,
	Eduard