2019-08-16 05:43:13

by Christophe Leroy

[permalink] [raw]
Subject: [PATCH 4/5] powerpc/mm: Simplify update_mmu_cache() on BOOK3S32

On BOOK3S32, hash_preload() neither use is_exec nor trap,
so drop those parameters and simplify update_mmu_cached().

Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/mm/book3s32/mmu.c | 29 +++++++----------------------
arch/powerpc/mm/mmu_decl.h | 3 +--
arch/powerpc/mm/pgtable_32.c | 2 +-
3 files changed, 9 insertions(+), 25 deletions(-)

diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
index 3e3c4077cdb7..3a62bf99f93f 100644
--- a/arch/powerpc/mm/book3s32/mmu.c
+++ b/arch/powerpc/mm/book3s32/mmu.c
@@ -297,8 +297,7 @@ void __init setbat(int index, unsigned long virt, phys_addr_t phys,
/*
* Preload a translation in the hash table
*/
-void hash_preload(struct mm_struct *mm, unsigned long ea,
- bool is_exec, unsigned long trap)
+void hash_preload(struct mm_struct *mm, unsigned long ea)
{
pmd_t *pmd;

@@ -324,34 +323,20 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
* We don't need to worry about _PAGE_PRESENT here because we are
* called with either mm->page_table_lock held or ptl lock held
*/
- unsigned long trap;
- bool is_exec;

/* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
if (!pte_young(*ptep) || address >= TASK_SIZE)
return;

- /* We try to figure out if we are coming from an instruction
- * access fault and pass that down to __hash_page so we avoid
- * double-faulting on execution of fresh text. We have to test
- * for regs NULL since init will get here first thing at boot
- *
- * We also avoid filling the hash if not coming from a fault
- */
+ /* We have to test for regs NULL since init will get here first thing at boot */
+ if (!current->thread.regs)
+ return;

- trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL;
- switch (trap) {
- case 0x300:
- is_exec = false;
- break;
- case 0x400:
- is_exec = true;
- break;
- default:
+ /* We also avoid filling the hash if not coming from a fault */
+ if (TRAP(current->thread.regs) != 0x300 && TRAP(current->thread.regs) != 0x400)
return;
- }

- hash_preload(vma->vm_mm, address, is_exec, trap);
+ hash_preload(vma->vm_mm, address);
}

/*
diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 9f325a7a09cb..adbaf2167214 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -91,8 +91,7 @@ void print_system_hash_info(void);

#ifdef CONFIG_PPC32

-void hash_preload(struct mm_struct *mm, unsigned long ea,
- bool is_exec, unsigned long trap);
+void hash_preload(struct mm_struct *mm, unsigned long ea);

extern void mapin_ram(void);
extern void setbat(int index, unsigned long virt, phys_addr_t phys,
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 35cb96cfc258..97f401a06fcc 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -252,7 +252,7 @@ static void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
map_kernel_page(v, p, ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL);
#ifdef CONFIG_PPC_BOOK3S_32
if (ktext)
- hash_preload(&init_mm, v, false, 0x300);
+ hash_preload(&init_mm, v);
#endif
v += PAGE_SIZE;
p += PAGE_SIZE;
--
2.13.3