sparc64: Reduce TLB flushes during hugepte changes
During hugepage map/unmap, TSB and TLB flushes are currently
issued at every PAGE_SIZE'd boundary which is unnecessary.
We now issue the flush at REAL_HPAGE_SIZE boundaries only.
Without this patch workloads which unmap a large hugepage
backed VMA region get CPU lockups due to excessive TLB
flush calls.
Orabug: 22365539, 22643230, 22995196
Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/mm/tsb.c b/arch/sparc/mm/tsb.c
index a065766..a0604a4 100644
--- a/arch/sparc/mm/tsb.c
+++ b/arch/sparc/mm/tsb.c
@@ -76,14 +76,15 @@
spin_lock_irqsave(&mm->context.lock, flags);
- base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
- nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
- if (tlb_type == cheetah_plus || tlb_type == hypervisor)
- base = __pa(base);
- __flush_tsb_one(tb, PAGE_SHIFT, base, nentries);
-
+ if (!tb->huge) {
+ base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
+ nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
+ if (tlb_type == cheetah_plus || tlb_type == hypervisor)
+ base = __pa(base);
+ __flush_tsb_one(tb, PAGE_SHIFT, base, nentries);
+ }
#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
- if (mm->context.tsb_block[MM_TSB_HUGE].tsb) {
+ if (tb->huge && mm->context.tsb_block[MM_TSB_HUGE].tsb) {
base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb;
nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries;
if (tlb_type == cheetah_plus || tlb_type == hypervisor)
@@ -94,20 +95,21 @@
spin_unlock_irqrestore(&mm->context.lock, flags);
}
-void flush_tsb_user_page(struct mm_struct *mm, unsigned long vaddr)
+void flush_tsb_user_page(struct mm_struct *mm, unsigned long vaddr, bool huge)
{
unsigned long nentries, base, flags;
spin_lock_irqsave(&mm->context.lock, flags);
- base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
- nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
- if (tlb_type == cheetah_plus || tlb_type == hypervisor)
- base = __pa(base);
- __flush_tsb_one_entry(base, vaddr, PAGE_SHIFT, nentries);
-
+ if (!huge) {
+ base = (unsigned long) mm->context.tsb_block[MM_TSB_BASE].tsb;
+ nentries = mm->context.tsb_block[MM_TSB_BASE].tsb_nentries;
+ if (tlb_type == cheetah_plus || tlb_type == hypervisor)
+ base = __pa(base);
+ __flush_tsb_one_entry(base, vaddr, PAGE_SHIFT, nentries);
+ }
#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
- if (mm->context.tsb_block[MM_TSB_HUGE].tsb) {
+ if (huge && mm->context.tsb_block[MM_TSB_HUGE].tsb) {
base = (unsigned long) mm->context.tsb_block[MM_TSB_HUGE].tsb;
nentries = mm->context.tsb_block[MM_TSB_HUGE].tsb_nentries;
if (tlb_type == cheetah_plus || tlb_type == hypervisor)