kernel_samsung_a34x-permissive/arch/parisc/include/asm/tlbflush.h
2024-04-28 15:49:01 +02:00

93 lines
2.6 KiB
C
Executable file

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PARISC_TLBFLUSH_H
#define _PARISC_TLBFLUSH_H
/* TLB flushing routines.... */
#include <linux/mm.h>
#include <linux/sched.h>
#include <asm/mmu_context.h>
/* This is for the serialisation of PxTLB broadcasts. At least on the
* N class systems, only one PxTLB inter processor broadcast can be
* active at any one time on the Merced bus. This tlb purge
* synchronisation is fairly lightweight and harmless so we activate
* it on all systems not just the N class.
* It is also used to ensure PTE updates are atomic and consistent
* with the TLB.
*/
extern spinlock_t pa_tlb_lock;
#define purge_tlb_start(flags) spin_lock_irqsave(&pa_tlb_lock, flags)
#define purge_tlb_end(flags) spin_unlock_irqrestore(&pa_tlb_lock, flags)
extern void flush_tlb_all(void);
extern void flush_tlb_all_local(void *);
#define smp_flush_tlb_all() flush_tlb_all()
int __flush_tlb_range(unsigned long sid,
unsigned long start, unsigned long end);
#define flush_tlb_range(vma, start, end) \
__flush_tlb_range((vma)->vm_mm->context, start, end)
#define flush_tlb_kernel_range(start, end) \
__flush_tlb_range(0, start, end)
/*
* flush_tlb_mm()
*
* The code to switch to a new context is NOT valid for processes
* which play with the space id's. Thus, we have to preserve the
* space and just flush the entire tlb. However, the compilers,
* dynamic linker, etc, do not manipulate space id's, so there
* could be a significant performance benefit in switching contexts
* and not flushing the whole tlb.
*/
static inline void flush_tlb_mm(struct mm_struct *mm)
{
BUG_ON(mm == &init_mm); /* Should never happen */
#if 1 || defined(CONFIG_SMP)
/* Except for very small threads, flushing the whole TLB is
* faster than using __flush_tlb_range. The pdtlb and pitlb
* instructions are very slow because of the TLB broadcast.
* It might be faster to do local range flushes on all CPUs
* on PA 2.0 systems.
*/
flush_tlb_all();
#else
/* FIXME: currently broken, causing space id and protection ids
* to go out of sync, resulting in faults on userspace accesses.
* This approach needs further investigation since running many
* small applications (e.g., GCC testsuite) is faster on HP-UX.
*/
if (mm) {
if (mm->context != 0)
free_sid(mm->context);
mm->context = alloc_sid();
if (mm == current->active_mm)
load_context(mm->context);
}
#endif
}
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long addr)
{
unsigned long flags, sid;
sid = vma->vm_mm->context;
purge_tlb_start(flags);
mtsp(sid, 1);
pdtlb(addr);
if (unlikely(split_tlb))
pitlb(addr);
purge_tlb_end(flags);
}
#endif