From 66d16ed45d19600abd72dbd55bd2018437b24b73 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Fri, 19 Oct 2007 20:35:03 +0200 Subject: [PATCH] x86: implement missing x86_64 function smp_call_function_mask() This patch defines the missing function smp_call_function_mask() for x86_64, this is more or less a cut&paste of i386 function. It removes also some duplicate code. This function is needed by KVM to execute a function on some CPUs. AK: Fixed description AK: Moved WARN_ON(irqs_disabled) one level up to not warn in the panic case. [ tglx: arch/x86 adaptation ] Signed-off-by: Laurent Vivier Signed-off-by: Andi Kleen Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/smp_64.c | 119 +++++++++++++++++++++------------------ include/asm-x86/smp_64.h | 2 + 2 files changed, 65 insertions(+), 56 deletions(-) diff --git a/arch/x86/kernel/smp_64.c b/arch/x86/kernel/smp_64.c index 5c2964727d1..03fa6ed559c 100644 --- a/arch/x86/kernel/smp_64.c +++ b/arch/x86/kernel/smp_64.c @@ -322,17 +322,27 @@ void unlock_ipi_call_lock(void) } /* - * this function sends a 'generic call function' IPI to one other CPU - * in the system. - * - * cpu is a standard Linux logical CPU number. + * this function sends a 'generic call function' IPI to all other CPU + * of the system defined in the mask. */ -static void -__smp_call_function_single(int cpu, void (*func) (void *info), void *info, - int nonatomic, int wait) + +static int +__smp_call_function_mask(cpumask_t mask, + void (*func)(void *), void *info, + int wait) { struct call_data_struct data; - int cpus = 1; + cpumask_t allbutself; + int cpus; + + allbutself = cpu_online_map; + cpu_clear(smp_processor_id(), allbutself); + + cpus_and(mask, mask, allbutself); + cpus = cpus_weight(mask); + + if (!cpus) + return 0; data.func = func; data.info = info; @@ -343,19 +353,55 @@ __smp_call_function_single(int cpu, void (*func) (void *info), void *info, call_data = &data; wmb(); - /* Send a message to all other CPUs and wait for them to respond */ - send_IPI_mask(cpumask_of_cpu(cpu), CALL_FUNCTION_VECTOR); + + /* Send a message to other CPUs */ + if (cpus_equal(mask, allbutself)) + 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) - return; + return 0; while (atomic_read(&data.finished) != cpus) cpu_relax(); + + return 0; +} +/** + * 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. + */ +int smp_call_function_mask(cpumask_t mask, + void (*func)(void *), void *info, + int wait) +{ + int ret; + + /* Can deadlock when called with interrupts disabled */ + WARN_ON(irqs_disabled()); + + spin_lock(&call_lock); + ret = __smp_call_function_mask(mask, func, info, wait); + spin_unlock(&call_lock); + return ret; } +EXPORT_SYMBOL(smp_call_function_mask); /* * smp_call_function_single - Run a function on a specific CPU @@ -374,6 +420,7 @@ int smp_call_function_single (int cpu, void (*func) (void *info), void *info, int nonatomic, int wait) { /* prevent preemption and reschedule on another processor */ + int ret; int me = get_cpu(); /* Can deadlock when called with interrupts disabled */ @@ -387,50 +434,13 @@ int smp_call_function_single (int cpu, void (*func) (void *info), void *info, return 0; } - spin_lock(&call_lock); - __smp_call_function_single(cpu, func, info, nonatomic, wait); - spin_unlock(&call_lock); + ret = smp_call_function_mask(cpumask_of_cpu(cpu), func, info, wait); + put_cpu(); - return 0; + return ret; } EXPORT_SYMBOL(smp_call_function_single); -/* - * this function sends a 'generic call function' IPI to all other CPUs - * in the system. - */ -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; - wmb(); - /* 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) - return; - - while (atomic_read(&data.finished) != cpus) - cpu_relax(); -} - /* * smp_call_function - run a function on all other CPUs. * @func: The function to run. This must be fast and non-blocking. @@ -449,10 +459,7 @@ static void __smp_call_function (void (*func) (void *info), void *info, int smp_call_function (void (*func) (void *info), void *info, int nonatomic, int wait) { - spin_lock(&call_lock); - __smp_call_function(func,info,nonatomic,wait); - spin_unlock(&call_lock); - return 0; + return smp_call_function_mask(cpu_online_map, func, info, wait); } EXPORT_SYMBOL(smp_call_function); @@ -479,7 +486,7 @@ void smp_send_stop(void) /* Don't deadlock on the call lock in panic */ nolock = !spin_trylock(&call_lock); local_irq_save(flags); - __smp_call_function(stop_this_cpu, NULL, 0, 0); + __smp_call_function_mask(cpu_online_map, stop_this_cpu, NULL, 0); if (!nolock) spin_unlock(&call_lock); disable_local_APIC(); diff --git a/include/asm-x86/smp_64.h b/include/asm-x86/smp_64.h index d30e9b684fd..9d35018e54f 100644 --- a/include/asm-x86/smp_64.h +++ b/include/asm-x86/smp_64.h @@ -37,6 +37,8 @@ extern void lock_ipi_call_lock(void); extern void unlock_ipi_call_lock(void); extern int smp_num_siblings; extern void smp_send_reschedule(int cpu); +extern int smp_call_function_mask(cpumask_t mask, void (*func)(void *), + void *info, int wait); /* * cpu_sibling_map and cpu_core_map now live -- 2.41.1