diff options
Diffstat (limited to 'arch/arm/include/asm/switch_to.h')
| -rw-r--r-- | arch/arm/include/asm/switch_to.h | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/arm/include/asm/switch_to.h b/arch/arm/include/asm/switch_to.h new file mode 100644 index 000000000..937234851 --- /dev/null +++ b/arch/arm/include/asm/switch_to.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_ARM_SWITCH_TO_H +#define __ASM_ARM_SWITCH_TO_H + +#include <linux/thread_info.h> +#include <asm/smp_plat.h> + +/* + * For v7 SMP cores running a preemptible kernel we may be pre-empted + * during a TLB maintenance operation, so execute an inner-shareable dsb + * to ensure that the maintenance completes in case we migrate to another + * CPU. + */ +#if defined(CONFIG_PREEMPTION) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7) +#define __complete_pending_tlbi() dsb(ish) +#else +#define __complete_pending_tlbi() +#endif + +/* + * switch_to(prev, next) should switch from task `prev' to `next' + * `prev' will never be the same as `next'. schedule() itself + * contains the memory barrier to tell GCC not to cache `current'. + */ +extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *); + +#define switch_to(prev,next,last) \ +do { \ + __complete_pending_tlbi(); \ + if (IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || is_smp()) \ + __this_cpu_write(__entry_task, next); \ + last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \ +} while (0) + +#endif /* __ASM_ARM_SWITCH_TO_H */ |