arch/parisc/include/asm/tlbflush.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _PARISC_TLBFLUSH_H
   3 #define _PARISC_TLBFLUSH_H
   4
   5 /* TLB flushing routines.... */
   6
   7 #include <linux/mm.h>
   8 #include <linux/sched.h>
   9 #include <asm/mmu_context.h>
  10
  11 extern void flush_tlb_all(void);
  12 extern void flush_tlb_all_local(void *);
  13
  14 #define smp_flush_tlb_all()     flush_tlb_all()
  15
  16 int __flush_tlb_range(unsigned long sid,
  17         unsigned long start, unsigned long end);
  18
  19 #define flush_tlb_range(vma, start, end) \
  20         __flush_tlb_range((vma)->vm_mm->context, start, end)
  21
  22 #define flush_tlb_kernel_range(start, end) \
  23         __flush_tlb_range(0, start, end)
  24
  25 /*
  26  * flush_tlb_mm()
  27  *
  28  * The code to switch to a new context is NOT valid for processes
  29  * which play with the space id's.  Thus, we have to preserve the
  30  * space and just flush the entire tlb.  However, the compilers,
  31  * dynamic linker, etc, do not manipulate space id's, so there
  32  * could be a significant performance benefit in switching contexts
  33  * and not flushing the whole tlb.
  34  */
  35
  36 static inline void flush_tlb_mm(struct mm_struct *mm)
  37 {
  38         BUG_ON(mm == &init_mm); /* Should never happen */
  39
  40 #if 1 || defined(CONFIG_SMP)
  41         /* Except for very small threads, flushing the whole TLB is
  42          * faster than using __flush_tlb_range.  The pdtlb and pitlb
  43          * instructions are very slow because of the TLB broadcast.
  44          * It might be faster to do local range flushes on all CPUs
  45          * on PA 2.0 systems.
  46          */
  47         flush_tlb_all();
  48 #else
  49         /* FIXME: currently broken, causing space id and protection ids
  50          * to go out of sync, resulting in faults on userspace accesses.
  51          * This approach needs further investigation since running many
  52          * small applications (e.g., GCC testsuite) is faster on HP-UX.
  53          */
  54         if (mm) {
  55                 if (mm->context != 0)
  56                         free_sid(mm->context);
  57                 mm->context = alloc_sid();
  58                 if (mm == current->active_mm)
  59                         load_context(mm->context);
  60         }
  61 #endif
  62 }
  63
  64 static inline void flush_tlb_page(struct vm_area_struct *vma,
  65         unsigned long addr)
  66 {
  67         purge_tlb_entries(vma->vm_mm, addr);
  68 }
  69 #endif