From 3b16cf874861436725c43ba0b68bdd799297be7c Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 26 Jun 2008 11:21:54 +0200 Subject: x86: convert to generic helpers for IPI function calls This converts x86, x86-64, and xen to use the new helpers for smp_call_function() and friends, and adds support for smp_call_function_single(). Acked-by: Ingo Molnar Acked-by: Jeremy Fitzhardinge Signed-off-by: Jens Axboe --- arch/x86/kernel/smp.c | 158 +++++++------------------------------------------- 1 file changed, 20 insertions(+), 138 deletions(-) (limited to 'arch/x86/kernel/smp.c') diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index 0cb7aad..575aa3d 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c @@ -121,132 +121,23 @@ static void native_smp_send_reschedule(int cpu) send_IPI_mask(cpumask_of_cpu(cpu), RESCHEDULE_VECTOR); } -/* - * Structure and data for smp_call_function(). This is designed to minimise - * static memory requirements. It also looks cleaner. - */ -static DEFINE_SPINLOCK(call_lock); - -struct call_data_struct { - void (*func) (void *info); - void *info; - atomic_t started; - atomic_t finished; - int wait; -}; - -void lock_ipi_call_lock(void) +void native_send_call_func_single_ipi(int cpu) { - spin_lock_irq(&call_lock); -} - -void unlock_ipi_call_lock(void) -{ - spin_unlock_irq(&call_lock); -} - -static struct call_data_struct *call_data; - -static void __smp_call_function(void (*func) (void *info), void *info, - int nonatomic, int wait) -{ - struct call_data_struct data; - int cpus = num_online_cpus() - 1; - - if (!cpus) - return; - - data.func = func; - data.info = info; - atomic_set(&data.started, 0); - data.wait = wait; - if (wait) - atomic_set(&data.finished, 0); - - call_data = &data; - mb(); - - /* Send a message to all other CPUs and wait for them to respond */ - send_IPI_allbutself(CALL_FUNCTION_VECTOR); - - /* Wait for response */ - while (atomic_read(&data.started) != cpus) - cpu_relax(); - - if (wait) - while (atomic_read(&data.finished) != cpus) - cpu_relax(); + send_IPI_mask(cpumask_of_cpu(cpu), CALL_FUNCTION_SINGLE_VECTOR); } - -/** - * smp_call_function_mask(): Run a function on a set of other CPUs. - * @mask: The set of cpus to run on. Must not include the current cpu. - * @func: The function to run. This must be fast and non-blocking. - * @info: An arbitrary pointer to pass to the function. - * @wait: If true, wait (atomically) until function has completed on other CPUs. - * - * Returns 0 on success, else a negative status code. - * - * If @wait is true, then returns once @func has returned; otherwise - * it returns just before the target cpu calls @func. - * - * You must not call this function with disabled interrupts or from a - * hardware interrupt handler or from a bottom half handler. - */ -static int -native_smp_call_function_mask(cpumask_t mask, - void (*func)(void *), void *info, - int wait) +void native_send_call_func_ipi(cpumask_t mask) { - struct call_data_struct data; cpumask_t allbutself; - int cpus; - - /* Can deadlock when called with interrupts disabled */ - WARN_ON(irqs_disabled()); - - /* Holding any lock stops cpus from going down. */ - spin_lock(&call_lock); allbutself = cpu_online_map; cpu_clear(smp_processor_id(), allbutself); - cpus_and(mask, mask, allbutself); - cpus = cpus_weight(mask); - - if (!cpus) { - spin_unlock(&call_lock); - return 0; - } - - data.func = func; - data.info = info; - atomic_set(&data.started, 0); - data.wait = wait; - if (wait) - atomic_set(&data.finished, 0); - - call_data = &data; - wmb(); - - /* Send a message to other CPUs */ if (cpus_equal(mask, allbutself) && cpus_equal(cpu_online_map, cpu_callout_map)) send_IPI_allbutself(CALL_FUNCTION_VECTOR); else send_IPI_mask(mask, CALL_FUNCTION_VECTOR); - - /* Wait for response */ - while (atomic_read(&data.started) != cpus) - cpu_relax(); - - if (wait) - while (atomic_read(&data.finished) != cpus) - cpu_relax(); - spin_unlock(&call_lock); - - return 0; } static void stop_this_cpu(void *dummy) @@ -268,18 +159,13 @@ static void stop_this_cpu(void *dummy) static void native_smp_send_stop(void) { - int nolock; unsigned long flags; if (reboot_force) return; - /* Don't deadlock on the call lock in panic */ - nolock = !spin_trylock(&call_lock); + smp_call_function(stop_this_cpu, NULL, 0, 0); local_irq_save(flags); - __smp_call_function(stop_this_cpu, NULL, 0, 0); - if (!nolock) - spin_unlock(&call_lock); disable_local_APIC(); local_irq_restore(flags); } @@ -301,33 +187,28 @@ void smp_reschedule_interrupt(struct pt_regs *regs) void smp_call_function_interrupt(struct pt_regs *regs) { - void (*func) (void *info) = call_data->func; - void *info = call_data->info; - int wait = call_data->wait; - ack_APIC_irq(); - /* - * Notify initiating CPU that I've grabbed the data and am - * about to execute the function - */ - mb(); - atomic_inc(&call_data->started); - /* - * At this point the info structure may be out of scope unless wait==1 - */ irq_enter(); - (*func)(info); + generic_smp_call_function_interrupt(); #ifdef CONFIG_X86_32 __get_cpu_var(irq_stat).irq_call_count++; #else add_pda(irq_call_count, 1); #endif irq_exit(); +} - if (wait) { - mb(); - atomic_inc(&call_data->finished); - } +void smp_call_function_single_interrupt(void) +{ + ack_APIC_irq(); + irq_enter(); + generic_smp_call_function_single_interrupt(); +#ifdef CONFIG_X86_32 + __get_cpu_var(irq_stat).irq_call_count++; +#else + add_pda(irq_call_count, 1); +#endif + irq_exit(); } struct smp_ops smp_ops = { @@ -338,7 +219,8 @@ struct smp_ops smp_ops = { .smp_send_stop = native_smp_send_stop, .smp_send_reschedule = native_smp_send_reschedule, - .smp_call_function_mask = native_smp_call_function_mask, + + .send_call_func_ipi = native_send_call_func_ipi, + .send_call_func_single_ipi = native_send_call_func_single_ipi, }; EXPORT_SYMBOL_GPL(smp_ops); - -- cgit v1.1