Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ed42acae authored by Russell King's avatar Russell King
Browse files

ARM: make_coherent: avoid recalculating the pfn for the modified page 



We already know the pfn for the page to be modified in make_coherent,
so let's stop recalculating it unnecessarily.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 56dd4709

arch/arm/mm/fault-armv.c

+6 −6
Original line number Diff line number Diff line
@@ -37,7 +37,7 @@ static unsigned long shared_pte_mask = L_PTE_MT_BUFFERABLE; 
 * without CONFIG_CPU_CACHE_VIPT) cannot support split page_table_lock.

 */

static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address,

	pte_t *ptep)

	unsigned long pfn, pte_t *ptep)

{

	pte_t entry = *ptep;

	int ret;
@@ -52,7 +52,6 @@ static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address, 
	 * fault (ie, is old), we can safely ignore any issues.

	 */

	if (ret && (pte_val(entry) & L_PTE_MT_MASK) != shared_pte_mask) {

		unsigned long pfn = pte_pfn(entry);

		flush_cache_page(vma, address, pfn);

		outer_flush_range((pfn << PAGE_SHIFT),

				  (pfn << PAGE_SHIFT) + PAGE_SIZE);
@@ -65,7 +64,8 @@ static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address, 
	return ret;

}



static int adjust_pte(struct vm_area_struct *vma, unsigned long address)

static int adjust_pte(struct vm_area_struct *vma, unsigned long address,

	unsigned long pfn)

{

	spinlock_t *ptl;

	pgd_t *pgd;
@@ -90,7 +90,7 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address) 
	pte = pte_offset_map_nested(pmd, address);

	spin_lock(ptl);



	ret = do_adjust_pte(vma, address, pte);

	ret = do_adjust_pte(vma, address, pfn, pte);



	spin_unlock(ptl);

	pte_unmap_nested(pte);
@@ -127,11 +127,11 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma, unsigne 
		if (!(mpnt->vm_flags & VM_MAYSHARE))

			continue;

		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;

		aliases += adjust_pte(mpnt, mpnt->vm_start + offset);

		aliases += adjust_pte(mpnt, mpnt->vm_start + offset, pfn);

	}

	flush_dcache_mmap_unlock(mapping);

	if (aliases)

		adjust_pte(vma, addr);

		adjust_pte(vma, addr, pfn);

	else

		flush_cache_page(vma, addr, pfn);

}