This converts arm to use the new helpers for smp_call_function() and friends, and adds support for smp_call_function_single(). Fixups and testing done by Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Russell King <rmk@xxxxxxxxxxxxxxxx> Signed-off-by: Jens Axboe <jens.axboe@xxxxxxxxxx> --- arch/arm/Kconfig | 1 + arch/arm/kernel/smp.c | 157 +++++-------------------------------------------- 2 files changed, 16 insertions(+), 142 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index b786e68..c72dae6 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -650,6 +650,7 @@ source "kernel/time/Kconfig" config SMP bool "Symmetric Multi-Processing (EXPERIMENTAL)" depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP) + select USE_GENERIC_SMP_HELPERS help This enables support for systems with more than one CPU. If you have a system with only one CPU, like most personal computers, say N. If diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index eefae1d..6344466 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -68,20 +68,10 @@ enum ipi_msg_type { IPI_TIMER, IPI_RESCHEDULE, IPI_CALL_FUNC, + IPI_CALL_FUNC_SINGLE, IPI_CPU_STOP, }; -struct smp_call_struct { - void (*func)(void *info); - void *info; - int wait; - cpumask_t pending; - cpumask_t unfinished; -}; - -static struct smp_call_struct * volatile smp_call_function_data; -static DEFINE_SPINLOCK(smp_call_function_lock); - int __cpuinit __cpu_up(unsigned int cpu) { struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu); @@ -366,114 +356,15 @@ static void send_ipi_message(cpumask_t callmap, enum ipi_msg_type msg) local_irq_restore(flags); } -/* - * You must not call this function with disabled interrupts, from a - * hardware interrupt handler, nor from a bottom half handler. - */ -static int smp_call_function_on_cpu(void (*func)(void *info), void *info, - int retry, int wait, cpumask_t callmap) -{ - struct smp_call_struct data; - unsigned long timeout; - int ret = 0; - - data.func = func; - data.info = info; - data.wait = wait; - - cpu_clear(smp_processor_id(), callmap); - if (cpus_empty(callmap)) - goto out; - - data.pending = callmap; - if (wait) - data.unfinished = callmap; - - /* - * try to get the mutex on smp_call_function_data - */ - spin_lock(&smp_call_function_lock); - smp_call_function_data = &data; - - send_ipi_message(callmap, IPI_CALL_FUNC); - - timeout = jiffies + HZ; - while (!cpus_empty(data.pending) && time_before(jiffies, timeout)) - barrier(); - - /* - * did we time out? - */ - if (!cpus_empty(data.pending)) { - /* - * this may be causing our panic - report it - */ - printk(KERN_CRIT - "CPU%u: smp_call_function timeout for %p(%p)\n" - " callmap %lx pending %lx, %swait\n", - smp_processor_id(), func, info, *cpus_addr(callmap), - *cpus_addr(data.pending), wait ? "" : "no "); - - /* - * TRACE - */ - timeout = jiffies + (5 * HZ); - while (!cpus_empty(data.pending) && time_before(jiffies, timeout)) - barrier(); - - if (cpus_empty(data.pending)) - printk(KERN_CRIT " RESOLVED\n"); - else - printk(KERN_CRIT " STILL STUCK\n"); - } - - /* - * whatever happened, we're done with the data, so release it - */ - smp_call_function_data = NULL; - spin_unlock(&smp_call_function_lock); - - if (!cpus_empty(data.pending)) { - ret = -ETIMEDOUT; - goto out; - } - - if (wait) - while (!cpus_empty(data.unfinished)) - barrier(); - out: - - return 0; -} - -int smp_call_function(void (*func)(void *info), void *info, int retry, - int wait) +void arch_send_call_function_ipi(cpumask_t mask) { - return smp_call_function_on_cpu(func, info, retry, wait, - cpu_online_map); + send_ipi_message(mask, IPI_CALL_FUNC); } -EXPORT_SYMBOL_GPL(smp_call_function); -int smp_call_function_single(int cpu, void (*func)(void *info), void *info, - int retry, int wait) +void arch_send_call_function_single_ipi(int cpu) { - /* prevent preemption and reschedule on another processor */ - int current_cpu = get_cpu(); - int ret = 0; - - if (cpu == current_cpu) { - local_irq_disable(); - func(info); - local_irq_enable(); - } else - ret = smp_call_function_on_cpu(func, info, retry, wait, - cpumask_of_cpu(cpu)); - - put_cpu(); - - return ret; + send_ipi_message(cpumask_of_cpu(cpu), IPI_CALL_FUNC_SINGLE); } -EXPORT_SYMBOL_GPL(smp_call_function_single); void show_ipi_list(struct seq_file *p) { @@ -521,27 +412,6 @@ asmlinkage void __exception do_local_timer(struct pt_regs *regs) } #endif -/* - * ipi_call_function - handle IPI from smp_call_function() - * - * Note that we copy data out of the cross-call structure and then - * let the caller know that we're here and have done with their data - */ -static void ipi_call_function(unsigned int cpu) -{ - struct smp_call_struct *data = smp_call_function_data; - void (*func)(void *info) = data->func; - void *info = data->info; - int wait = data->wait; - - cpu_clear(cpu, data->pending); - - func(info); - - if (wait) - cpu_clear(cpu, data->unfinished); -} - static DEFINE_SPINLOCK(stop_lock); /* @@ -611,7 +481,11 @@ asmlinkage void __exception do_IPI(struct pt_regs *regs) break; case IPI_CALL_FUNC: - ipi_call_function(cpu); + generic_smp_call_function_interrupt(); + break; + + case IPI_CALL_FUNC_SINGLE: + generic_smp_call_function_single_interrupt(); break; case IPI_CPU_STOP: @@ -662,14 +536,13 @@ int setup_profiling_timer(unsigned int multiplier) } static int -on_each_cpu_mask(void (*func)(void *), void *info, int retry, int wait, - cpumask_t mask) +on_each_cpu_mask(void (*func)(void *), void *info, int wait, cpumask_t mask) { int ret = 0; preempt_disable(); - ret = smp_call_function_on_cpu(func, info, retry, wait, mask); + ret = smp_call_function_mask(mask, func, info, wait); if (cpu_isset(smp_processor_id(), mask)) func(info); @@ -738,7 +611,7 @@ void flush_tlb_mm(struct mm_struct *mm) { cpumask_t mask = mm->cpu_vm_mask; - on_each_cpu_mask(ipi_flush_tlb_mm, mm, 1, 1, mask); + on_each_cpu_mask(ipi_flush_tlb_mm, mm, 1, mask); } void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr) @@ -749,7 +622,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr) ta.ta_vma = vma; ta.ta_start = uaddr; - on_each_cpu_mask(ipi_flush_tlb_page, &ta, 1, 1, mask); + on_each_cpu_mask(ipi_flush_tlb_page, &ta, 1, mask); } void flush_tlb_kernel_page(unsigned long kaddr) @@ -771,7 +644,7 @@ void flush_tlb_range(struct vm_area_struct *vma, ta.ta_start = start; ta.ta_end = end; - on_each_cpu_mask(ipi_flush_tlb_range, &ta, 1, 1, mask); + on_each_cpu_mask(ipi_flush_tlb_range, &ta, 1, mask); } void flush_tlb_kernel_range(unsigned long start, unsigned long end) -- 1.5.5.1.57.g5909c -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html