linux/arch/arm/include/asm/switch_to.h
Ard Biesheuvel 4a2f57ac7d ARM: 9158/1: leave it to core code to manage thread_info::cpu
Since commit bcf9033e5449 ("sched: move CPU field back into thread_info
if THREAD_INFO_IN_TASK=y"), the CPU field in thread_info went back to
being managed by the core code, so we no longer have to keep it in sync
in arch code.

While at it, mark THREAD_INFO_IN_TASK as done for ARM in the
documentation.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-17 11:34:31 +00:00

35 lines
1.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ARM_SWITCH_TO_H
#define __ASM_ARM_SWITCH_TO_H
#include <linux/thread_info.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)) \
__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 */