diff options
Diffstat (limited to 'arch/mips/mm/c-r4k.c')
| -rw-r--r-- | arch/mips/mm/c-r4k.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c index 2a4bb50..57374f0 100644 --- a/arch/mips/mm/c-r4k.c +++ b/arch/mips/mm/c-r4k.c @@ -56,7 +56,9 @@ * @type: Type of cache operations (R4K_HIT or R4K_INDEX). * * Decides whether a cache op needs to be performed on every core in the system. - * This may change depending on the @type of cache operation. + * This may change depending on the @type of cache operation, as well as the set + * of online CPUs, so preemption should be disabled by the caller to prevent CPU + * hotplug from changing the result. * * Returns: 1 if the cache operation @type should be done on every core in * the system. @@ -71,9 +73,15 @@ static inline bool r4k_op_needs_ipi(unsigned int type) /* * Hardware doesn't globalize the required cache ops, so SMP calls may - * be needed. + * be needed, but only if there are foreign CPUs (non-siblings with + * separate caches). */ - return true; + /* cpu_foreign_map[] undeclared when !CONFIG_SMP */ +#ifdef CONFIG_SMP + return !cpumask_empty(&cpu_foreign_map[0]); +#else + return false; +#endif } /* @@ -90,7 +98,8 @@ static inline void r4k_on_each_cpu(unsigned int type, { preempt_disable(); if (r4k_op_needs_ipi(type)) - smp_call_function_many(&cpu_foreign_map, func, info, 1); + smp_call_function_many(&cpu_foreign_map[smp_processor_id()], + func, info, 1); func(info); preempt_enable(); } |