leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

arm64: tlbflush: Allow stride to be specified for __flush_tlb_range()

Browse Source 
When we are unmapping intermediate page-table entries or huge pages, we
don't need to issue a TLBI instruction for every PAGE_SIZE chunk in the
VA range being unmapped.

Allow the invalidation stride to be passed to __flush_tlb_range(), and
adjust our "just nuke the ASID" heuristic to take this into account.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Will Deacon 2018-08-23 19:26:21 +01:00 committed by Catalin Marinas
parent d8289d3a58
commit 67a902ac59
2 changed files with 10 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/arm64/include/asm/tlb.h
View File

@ -53,7 +53,7 @@ static inline void tlb_flush(struct mmu_gather *tlb)
* the __(pte|pmd|pud)_free_tlb() functions, so last level
* TLBI is sufficient here.
*/
__flush_tlb_range(&vma, tlb->start, tlb->end, true);
__flush_tlb_range(&vma, tlb->start, tlb->end, PAGE_SIZE, true);
}
static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,

15
arch/arm64/include/asm/tlbflush.h
View File

@ -149,25 +149,28 @@ static inline void flush_tlb_page(struct vm_area_struct *vma,
* This is meant to avoid soft lock-ups on large TLB flushing ranges and not
* necessarily a performance improvement.
*/
#define MAX_TLB_RANGE (1024UL << PAGE_SHIFT)
#define MAX_TLBI_OPS 1024UL
static inline void __flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end,
bool last_level)
unsigned long stride, bool last_level)
{
unsigned long asid = ASID(vma->vm_mm);
unsigned long addr;
if ((end - start) > MAX_TLB_RANGE) {
if ((end - start) > (MAX_TLBI_OPS * stride)) {
flush_tlb_mm(vma->vm_mm);
return;
}
/* Convert the stride into units of 4k */
stride >>= 12;
start = __TLBI_VADDR(start, asid);
end = __TLBI_VADDR(end, asid);
dsb(ishst);
for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12)) {
for (addr = start; addr < end; addr += stride) {
if (last_level) {
__tlbi(vale1is, addr);
__tlbi_user(vale1is, addr);
@ -186,14 +189,14 @@ static inline void flush_tlb_range(struct vm_area_struct *vma,
* We cannot use leaf-only invalidation here, since we may be invalidating
* table entries as part of collapsing hugepages or moving page tables.
*/
__flush_tlb_range(vma, start, end, false);
__flush_tlb_range(vma, start, end, PAGE_SIZE, false);
}
static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
unsigned long addr;
if ((end - start) > MAX_TLB_RANGE) {
if ((end - start) > (MAX_TLBI_OPS * PAGE_SIZE)) {
flush_tlb_all();
return;
}