From c2147a5092cfe13dbf3210e54e8a622015edeecc Mon Sep 17 00:00:00 2001 From: Eduard - Gabriel Munteanu Date: Fri, 25 Jul 2008 19:45:11 -0700 Subject: Better interface for hooking early initcalls Added early initcall (pre-SMP) support, using an identical interface to that of regular initcalls. Functions called from do_pre_smp_initcalls() could be converted to use this cleaner interface. This is required by CPU hotplug, because early users have to register notifiers before going SMP. One such CPU hotplug user is the relay interface with buffer-only channels, which needs to register such a notifier, to be usable in early code. This in turn is used by kmemtrace. Signed-off-by: Eduard - Gabriel Munteanu Cc: Tom Zanussi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/main.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 0604cbcaf1e4..b6fec08dbbef 100644 --- a/init/main.c +++ b/init/main.c @@ -743,13 +743,13 @@ static void __init do_one_initcall(initcall_t fn) } -extern initcall_t __initcall_start[], __initcall_end[]; +extern initcall_t __initcall_start[], __initcall_end[], __early_initcall_end[]; static void __init do_initcalls(void) { initcall_t *call; - for (call = __initcall_start; call < __initcall_end; call++) + for (call = __early_initcall_end; call < __initcall_end; call++) do_one_initcall(*call); /* Make sure there is no pending stuff from the initcall sequence */ @@ -783,6 +783,14 @@ static int __init nosoftlockup_setup(char *str) } __setup("nosoftlockup", nosoftlockup_setup); +static void __init __do_pre_smp_initcalls(void) +{ + initcall_t *call; + + for (call = __initcall_start; call < __early_initcall_end; call++) + do_one_initcall(*call); +} + static void __init do_pre_smp_initcalls(void) { extern int spawn_ksoftirqd(void); @@ -865,6 +873,7 @@ static int __init kernel_init(void * unused) smp_prepare_cpus(setup_max_cpus); + __do_pre_smp_initcalls(); do_pre_smp_initcalls(); smp_init(); -- cgit v1.2.3 From 7babe8db99d305340cf4828ce1f5a1481d5622ef Mon Sep 17 00:00:00 2001 From: Eduard - Gabriel Munteanu Date: Fri, 25 Jul 2008 19:45:11 -0700 Subject: Full conversion to early_initcall() interface, remove old interface 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. [akpm@linux-foundation.org: cleanups] [akpm@linux-foundation.org: build fix] [kosaki.motohiro@jp.fujitsu.com: warning fix] [kosaki.motohiro@jp.fujitsu.com: warning fix] Signed-off-by: Eduard - Gabriel Munteanu Cc: Tom Zanussi Signed-off-by: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 9 --------- include/linux/smp.h | 5 ----- init/main.c | 23 +---------------------- kernel/sched.c | 5 ++++- kernel/smp.c | 4 +++- kernel/softirq.c | 3 ++- kernel/softlockup.c | 25 ++++++++++++++++++++++--- 7 files changed, 32 insertions(+), 42 deletions(-) (limited to 'init/main.c') diff --git a/include/linux/sched.h b/include/linux/sched.h index 3260a5c42b91..adb8077dc463 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; @@ -2222,14 +2221,6 @@ 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 48262f86c969..66484d4a8459 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -74,15 +74,10 @@ 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); void ipi_call_lock(void); void ipi_call_unlock(void); void ipi_call_lock_irq(void); void ipi_call_unlock_irq(void); -#else -static inline void init_call_single_data(void) -{ -} #endif /* diff --git a/init/main.c b/init/main.c index b6fec08dbbef..20fdc9884b77 100644 --- a/init/main.c +++ b/init/main.c @@ -774,16 +774,7 @@ 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; @@ -791,17 +782,6 @@ 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; @@ -873,7 +853,6 @@ 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 0047bd9b96aa..fde1a1026359 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6389,7 +6389,7 @@ 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; @@ -6399,7 +6399,10 @@ 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 462c785ca1ee..96fc7c0edc59 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; @@ -43,7 +43,9 @@ 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) { diff --git a/kernel/softirq.c b/kernel/softirq.c index f6b03d56c2bf..c506f266a6b9 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -630,7 +630,7 @@ 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); @@ -640,6 +640,7 @@ __init int spawn_ksoftirqd(void) register_cpu_notifier(&cpu_nfb); return 0; } +early_initcall(spawn_ksoftirqd); #ifdef CONFIG_SMP /* diff --git a/kernel/softlockup.c b/kernel/softlockup.c index 7bd8d1aadd5d..b75b492fbfcf 100644 --- a/kernel/softlockup.c +++ b/kernel/softlockup.c @@ -338,14 +338,33 @@ 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; - BUG_ON(err == NOTIFY_BAD); + if (nosoftlockup) + return 0; + + 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); -- cgit v1.2.3