From ec971ea5f2426a0bf9d5cca9a103743918c12978 Mon Sep 17 00:00:00 2001 From: Richard Zhao Date: Wed, 5 Sep 2012 01:08:59 +0200 Subject: ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp If CONFIG_SMP, cpufreq skips loops_per_jiffy update, because different arch has different per-cpu loops_per_jiffy definition. Signed-off-by: Richard Zhao Acked-by: Russell King Acked-by: Santosh Shilimkar Signed-off-by: Shawn Guo Signed-off-by: Rafael J. Wysocki --- arch/arm/kernel/smp.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) (limited to 'arch/arm/kernel/smp.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index ebd8ad2..8e03567 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -584,3 +585,56 @@ int setup_profiling_timer(unsigned int multiplier) { return -EINVAL; } + +#ifdef CONFIG_CPU_FREQ + +static DEFINE_PER_CPU(unsigned long, l_p_j_ref); +static DEFINE_PER_CPU(unsigned long, l_p_j_ref_freq); +static unsigned long global_l_p_j_ref; +static unsigned long global_l_p_j_ref_freq; + +static int cpufreq_callback(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct cpufreq_freqs *freq = data; + int cpu = freq->cpu; + + if (freq->flags & CPUFREQ_CONST_LOOPS) + return NOTIFY_OK; + + if (!per_cpu(l_p_j_ref, cpu)) { + per_cpu(l_p_j_ref, cpu) = + per_cpu(cpu_data, cpu).loops_per_jiffy; + per_cpu(l_p_j_ref_freq, cpu) = freq->old; + if (!global_l_p_j_ref) { + global_l_p_j_ref = loops_per_jiffy; + global_l_p_j_ref_freq = freq->old; + } + } + + if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) || + (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) || + (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) { + loops_per_jiffy = cpufreq_scale(global_l_p_j_ref, + global_l_p_j_ref_freq, + freq->new); + per_cpu(cpu_data, cpu).loops_per_jiffy = + cpufreq_scale(per_cpu(l_p_j_ref, cpu), + per_cpu(l_p_j_ref_freq, cpu), + freq->new); + } + return NOTIFY_OK; +} + +static struct notifier_block cpufreq_notifier = { + .notifier_call = cpufreq_callback, +}; + +static int __init register_cpufreq_notifier(void) +{ + return cpufreq_register_notifier(&cpufreq_notifier, + CPUFREQ_TRANSITION_NOTIFIER); +} +core_initcall(register_cpufreq_notifier); + +#endif -- cgit v1.1 From abcee5fb0dfbb248d883a2f6bdb4820abe3ac524 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 8 Sep 2011 09:06:10 +0100 Subject: ARM: SoC: add per-platform SMP operations This adds a 'struct smp_operations' to abstract the CPU initialization and hot plugging functions on SMP systems, which otherwise conflict in a multiplatform kernel. This also helps shmobile and potentially others that have more than one method to do these. To allow the kernel to continue building, the platform hooks are defined as weak symbols which are overrided by the platform code. Once all platforms are converted, the "weak" attribute will be removed and the function made static. Unlike the original version from Marc, this new version from Arnd does not use a generalized abstraction for per-soc data structures but only tries to solve the problem for the SMP operations. This way, we can collapse the previous four data structures into a single struct, which is less systematic but also easier to follow as a causal reader. Signed-off-by: Marc Zyngier Acked-by: Nicolas Pitre Signed-off-by: Arnd Bergmann --- arch/arm/kernel/smp.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 61 insertions(+), 1 deletion(-) (limited to 'arch/arm/kernel/smp.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index ebd8ad2..d924188 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -19,7 +19,6 @@ #include #include #include -#include #include #include #include @@ -27,6 +26,7 @@ #include #include +#include #include #include #include @@ -42,6 +42,7 @@ #include #include #include +#include /* * as from 2.5, kernels no longer have an init_tasks structure @@ -60,6 +61,14 @@ enum ipi_msg_type { static DECLARE_COMPLETION(cpu_running); +static struct smp_operations smp_ops; + +void __init smp_set_ops(struct smp_operations *ops) +{ + if (ops) + smp_ops = *ops; +}; + int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) { int ret; @@ -100,9 +109,60 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) return ret; } +/* platform specific SMP operations */ +void __attribute__((weak)) __init smp_init_cpus(void) +{ + if (smp_ops.smp_init_cpus) + smp_ops.smp_init_cpus(); +} + +void __attribute__((weak)) __init platform_smp_prepare_cpus(unsigned int max_cpus) +{ + if (smp_ops.smp_prepare_cpus) + smp_ops.smp_prepare_cpus(max_cpus); +} + +void __attribute__((weak)) __cpuinit platform_secondary_init(unsigned int cpu) +{ + if (smp_ops.smp_secondary_init) + smp_ops.smp_secondary_init(cpu); +} + +int __attribute__((weak)) __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + if (smp_ops.smp_boot_secondary) + return smp_ops.smp_boot_secondary(cpu, idle); + return -ENOSYS; +} + #ifdef CONFIG_HOTPLUG_CPU static void percpu_timer_stop(void); +int __attribute__((weak)) platform_cpu_kill(unsigned int cpu) +{ + if (smp_ops.cpu_kill) + return smp_ops.cpu_kill(cpu); + return 1; +} + +void __attribute__((weak)) platform_cpu_die(unsigned int cpu) +{ + if (smp_ops.cpu_die) + smp_ops.cpu_die(cpu); +} + +int __attribute__((weak)) platform_cpu_disable(unsigned int cpu) +{ + if (smp_ops.cpu_disable) + return smp_ops.cpu_disable(cpu); + + /* + * By default, allow disabling all CPUs except the first one, + * since this is special on a lot of platforms, e.g. because + * of clock tick interrupts. + */ + return cpu == 0 ? -EPERM : 0; +} /* * __cpu_disable runs on the processor to be shutdown. */ -- cgit v1.1 From ac6c7998712d55bd15aa2dd5ae85f5988c0cb526 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 27 Sep 2011 14:48:23 +0100 Subject: ARM: smp: Make SMP operations mandatory Now that all SMP platforms have been converted to use struct smp_operations, remove the "weak" attribute from the hooks in smp.c, and make the functions static wherever possible. Signed-off-by: Marc Zyngier Acked-by: Nicolas Pitre Signed-off-by: Arnd Bergmann --- arch/arm/kernel/smp.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'arch/arm/kernel/smp.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index d924188..ac3ce02 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -110,25 +110,25 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) } /* platform specific SMP operations */ -void __attribute__((weak)) __init smp_init_cpus(void) +void __init smp_init_cpus(void) { if (smp_ops.smp_init_cpus) smp_ops.smp_init_cpus(); } -void __attribute__((weak)) __init platform_smp_prepare_cpus(unsigned int max_cpus) +static void __init platform_smp_prepare_cpus(unsigned int max_cpus) { if (smp_ops.smp_prepare_cpus) smp_ops.smp_prepare_cpus(max_cpus); } -void __attribute__((weak)) __cpuinit platform_secondary_init(unsigned int cpu) +static void __cpuinit platform_secondary_init(unsigned int cpu) { if (smp_ops.smp_secondary_init) smp_ops.smp_secondary_init(cpu); } -int __attribute__((weak)) __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) +int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) { if (smp_ops.smp_boot_secondary) return smp_ops.smp_boot_secondary(cpu, idle); @@ -138,20 +138,20 @@ int __attribute__((weak)) __cpuinit boot_secondary(unsigned int cpu, struct task #ifdef CONFIG_HOTPLUG_CPU static void percpu_timer_stop(void); -int __attribute__((weak)) platform_cpu_kill(unsigned int cpu) +static int platform_cpu_kill(unsigned int cpu) { if (smp_ops.cpu_kill) return smp_ops.cpu_kill(cpu); return 1; } -void __attribute__((weak)) platform_cpu_die(unsigned int cpu) +static void platform_cpu_die(unsigned int cpu) { if (smp_ops.cpu_die) smp_ops.cpu_die(cpu); } -int __attribute__((weak)) platform_cpu_disable(unsigned int cpu) +static int platform_cpu_disable(unsigned int cpu) { if (smp_ops.cpu_disable) return smp_ops.cpu_disable(cpu); @@ -166,7 +166,7 @@ int __attribute__((weak)) platform_cpu_disable(unsigned int cpu) /* * __cpu_disable runs on the processor to be shutdown. */ -int __cpu_disable(void) +int __cpuinit __cpu_disable(void) { unsigned int cpu = smp_processor_id(); int ret; @@ -209,7 +209,7 @@ static DECLARE_COMPLETION(cpu_died); * called on the thread which is asking for a CPU to be shutdown - * waits until shutdown has completed, or it is timed out. */ -void __cpu_die(unsigned int cpu) +void __cpuinit __cpu_die(unsigned int cpu) { if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) { pr_err("CPU%u: cpu didn't die\n", cpu); -- cgit v1.1 From 28e8e29c616f947348cc66bea684d0035c76021a Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 12 Jun 2012 11:16:27 +0100 Subject: ARM: consolidate pen_release instead of having per platform definitions Almost each SMP platform defines pen_release to manage booting secondary CPUs. This of course clashes with the single zImage effort. Add the pen_release definition to the ARM SMP code, and remove all others. This should only be used by platforms which lack any kind of CPU power management... Reported-by: Arnd Bergmann Signed-off-by: Marc Zyngier Acked-by: Nicolas Pitre Signed-off-by: Arnd Bergmann --- arch/arm/kernel/smp.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'arch/arm/kernel/smp.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index ac3ce02..aa4ffe6 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -51,6 +51,12 @@ */ struct secondary_data secondary_data; +/* + * control for which core is the next to come out of the secondary + * boot "holding pen" + */ +volatile int __cpuinitdata pen_release = -1; + enum ipi_msg_type { IPI_TIMER = 2, IPI_RESCHEDULE, -- cgit v1.1 From 559a593905e583fca23229b916c016e5211c6766 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Wed, 19 Sep 2012 08:16:07 +0100 Subject: ARM: 7536/1: smp: Formalize an IPI for wakeup Remove the offset from ipi_msg_type and assume that SGI0 is the wakeup interrupt now that all WFI hotplug users call gic_raise_softirq() with 0 instead of 1. This allows us to track how many wakeup interrupts are sent and also removes the unknown IPI printk message for WFI hotplug based systems. Reviewed-by: Nicolas Pitre Signed-off-by: Stephen Boyd Signed-off-by: Russell King --- arch/arm/kernel/smp.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'arch/arm/kernel/smp.c') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index ebd8ad2..d98c37e 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -51,7 +51,8 @@ struct secondary_data secondary_data; enum ipi_msg_type { - IPI_TIMER = 2, + IPI_WAKEUP, + IPI_TIMER, IPI_RESCHEDULE, IPI_CALL_FUNC, IPI_CALL_FUNC_SINGLE, @@ -347,7 +348,8 @@ void arch_send_call_function_single_ipi(int cpu) } static const char *ipi_types[NR_IPI] = { -#define S(x,s) [x - IPI_TIMER] = s +#define S(x,s) [x] = s + S(IPI_WAKEUP, "CPU wakeup interrupts"), S(IPI_TIMER, "Timer broadcast interrupts"), S(IPI_RESCHEDULE, "Rescheduling interrupts"), S(IPI_CALL_FUNC, "Function call interrupts"), @@ -500,10 +502,13 @@ void handle_IPI(int ipinr, struct pt_regs *regs) unsigned int cpu = smp_processor_id(); struct pt_regs *old_regs = set_irq_regs(regs); - if (ipinr >= IPI_TIMER && ipinr < IPI_TIMER + NR_IPI) - __inc_irq_stat(cpu, ipi_irqs[ipinr - IPI_TIMER]); + if (ipinr < NR_IPI) + __inc_irq_stat(cpu, ipi_irqs[ipinr]); switch (ipinr) { + case IPI_WAKEUP: + break; + case IPI_TIMER: irq_enter(); ipi_timer(); -- cgit v1.1