From 2f304c0a0a55072b80957580f1b66256a615d8da Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 17 Jun 2008 10:45:23 +0200 Subject: [PATCH] mips: convert to generic helpers for IPI function calls This converts mips to use the new helpers for smp_call_function() and friends, and adds support for smp_call_function_single(). Not tested, but it compiles. mips shares the same IPI for smp_call_function() and smp_call_function_single(), since not all mips platforms have enough available IPIs to support seperate setups. Cc: Ralf Baechle Signed-off-by: Jens Axboe --- arch/mips/Kconfig | 1 + arch/mips/kernel/smp.c | 141 ++++------------------------------------ arch/mips/kernel/smtc.c | 1 - include/asm-mips/smp.h | 13 +--- 4 files changed, 15 insertions(+), 141 deletions(-) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index e5a7c5d9636..ea70d5a225c 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1763,6 +1763,7 @@ config SMP bool "Multi-Processing support" depends on SYS_SUPPORTS_SMP select IRQ_PER_CPU + 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/mips/kernel/smp.c b/arch/mips/kernel/smp.c index cdf87a9dd4b..c75b26cb61d 100644 --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -131,148 +131,29 @@ asmlinkage __cpuinit void start_secondary(void) cpu_idle(); } -DEFINE_SPINLOCK(smp_call_lock); - -struct call_data_struct *call_data; - -/* - * Run a function on all other CPUs. - * - * cpuset_t of all processors to run the function on. - * The function to run. This must be fast and non-blocking. - * An arbitrary pointer to pass to the function. - * If true, keep retrying until ready. - * If true, wait until function has completed on other CPUs. - * [RETURNS] 0 on success, else a negative status code. - * - * Does not return until remote CPUs are nearly ready to execute - * or are or have executed. - * - * You must not call this function with disabled interrupts or from a - * hardware interrupt handler or from a bottom half handler: - * - * CPU A CPU B - * Disable interrupts - * smp_call_function() - * Take call_lock - * Send IPIs - * Wait for all cpus to acknowledge IPI - * CPU A has not responded, spin waiting - * for cpu A to respond, holding call_lock - * smp_call_function() - * Spin waiting for call_lock - * Deadlock Deadlock - */ -int smp_call_function_mask(cpumask_t mask, void (*func) (void *info), - void *info, int retry, int wait) +void arch_send_call_function_ipi(cpumask_t mask) { - struct call_data_struct data; - int cpu = smp_processor_id(); - int cpus; - - /* - * Can die spectacularly if this CPU isn't yet marked online - */ - BUG_ON(!cpu_online(cpu)); - - cpu_clear(cpu, mask); - cpus = cpus_weight(mask); - if (!cpus) - return 0; - - /* Can deadlock when called with interrupts disabled */ - WARN_ON(irqs_disabled()); - - data.func = func; - data.info = info; - atomic_set(&data.started, 0); - data.wait = wait; - if (wait) - atomic_set(&data.finished, 0); - - spin_lock(&smp_call_lock); - call_data = &data; - smp_mb(); - - /* Send a message to all other CPUs and wait for them to respond */ mp_ops->send_ipi_mask(mask, SMP_CALL_FUNCTION); - - /* Wait for response */ - /* FIXME: lock-up detection, backtrace on lock-up */ - while (atomic_read(&data.started) != cpus) - barrier(); - - if (wait) - while (atomic_read(&data.finished) != cpus) - barrier(); - call_data = NULL; - spin_unlock(&smp_call_lock); - - return 0; } -int smp_call_function(void (*func) (void *info), void *info, int retry, - int wait) +/* + * We reuse the same vector for the single IPI + */ +void arch_send_call_function_single_ipi(int cpu) { - return smp_call_function_mask(cpu_online_map, func, info, retry, wait); + mp_ops->send_ipi_mask(cpumask_of_cpu(cpu), SMP_CALL_FUNCTION); } -EXPORT_SYMBOL(smp_call_function); +/* + * Call into both interrupt handlers, as we share the IPI for them + */ void smp_call_function_interrupt(void) { - void (*func) (void *info) = call_data->func; - void *info = call_data->info; - int wait = call_data->wait; - - /* - * Notify initiating CPU that I've grabbed the data and am - * about to execute the function. - */ - smp_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_single_interrupt(); + generic_smp_call_function_interrupt(); irq_exit(); - - if (wait) { - smp_mb(); - atomic_inc(&call_data->finished); - } -} - -int smp_call_function_single(int cpu, void (*func) (void *info), void *info, - int retry, int wait) -{ - int ret, me; - - /* - * Can die spectacularly if this CPU isn't yet marked online - */ - if (!cpu_online(cpu)) - return 0; - - me = get_cpu(); - BUG_ON(!cpu_online(me)); - - if (cpu == me) { - local_irq_disable(); - func(info); - local_irq_enable(); - put_cpu(); - return 0; - } - - ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, retry, - wait); - - put_cpu(); - return 0; } -EXPORT_SYMBOL(smp_call_function_single); static void stop_this_cpu(void *dummy) { diff --git a/arch/mips/kernel/smtc.c b/arch/mips/kernel/smtc.c index 3e863186cd2..a516286532a 100644 --- a/arch/mips/kernel/smtc.c +++ b/arch/mips/kernel/smtc.c @@ -877,7 +877,6 @@ static void ipi_resched_interrupt(void) /* Return from interrupt should be enough to cause scheduler check */ } - static void ipi_call_interrupt(void) { /* Invoke generic function invocation code in smp.c */ diff --git a/include/asm-mips/smp.h b/include/asm-mips/smp.h index 84fef1aeec0..0ff5b523ea7 100644 --- a/include/asm-mips/smp.h +++ b/include/asm-mips/smp.h @@ -35,16 +35,6 @@ extern int __cpu_logical_map[NR_CPUS]; #define NO_PROC_ID (-1) -struct call_data_struct { - void (*func)(void *); - void *info; - atomic_t started; - atomic_t finished; - int wait; -}; - -extern struct call_data_struct *call_data; - #define SMP_RESCHEDULE_YOURSELF 0x1 /* XXX braindead */ #define SMP_CALL_FUNCTION 0x2 @@ -67,4 +57,7 @@ static inline void smp_send_reschedule(int cpu) extern asmlinkage void smp_call_function_interrupt(void); +extern void arch_send_call_function_single_ipi(int cpu); +extern void arch_send_call_function_ipi(cpumask_t mask); + #endif /* __ASM_SMP_H */ -- 2.41.1