From 24e49ee3d76b70853a96520e46b8837e5eae65b2 Mon Sep 17 00:00:00 2001
From: Nitin Gupta <nitin.m.gupta@oracle.com>
Date: Wed, 30 Mar 2016 11:17:13 -0700
Subject: 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>
---
arch/sparc/mm/tlb.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
(limited to 'arch/sparc/mm/tlb.c')
diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c
index 9df2190c097e..f81cd9736700 100644
--- a/arch/sparc/mm/tlb.c
+++ b/arch/sparc/mm/tlb.c
@@ -67,7 +67,7 @@ void arch_leave_lazy_mmu_mode(void)
}
static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
- bool exec)
+ bool exec, bool huge)
{
struct tlb_batch *tb = &get_cpu_var(tlb_batch);
unsigned long nr;
@@ -84,13 +84,21 @@ static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
}
if (!tb->active) {
- flush_tsb_user_page(mm, vaddr);
+ flush_tsb_user_page(mm, vaddr, huge);
global_flush_tlb_page(mm, vaddr);
goto out;
}
- if (nr == 0)
+ if (nr == 0) {
tb->mm = mm;
+ tb->huge = huge;
+ }
+
+ if (tb->huge != huge) {
+ flush_tlb_pending();
+ tb->huge = huge;
+ nr = 0;
+ }
tb->vaddrs[nr] = vaddr;
tb->tlb_nr = ++nr;
@@ -104,6 +112,8 @@ out:
void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
pte_t *ptep, pte_t orig, int fullmm)
{
+ bool huge = is_hugetlb_pte(orig);
+
if (tlb_type != hypervisor &&
pte_dirty(orig)) {
unsigned long paddr, pfn = pte_pfn(orig);
@@ -129,7 +139,7 @@ void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
no_cache_flush:
if (!fullmm)
- tlb_batch_add_one(mm, vaddr, pte_exec(orig));
+ tlb_batch_add_one(mm, vaddr, pte_exec(orig), huge);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -145,7 +155,7 @@ static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr,
if (pte_val(*pte) & _PAGE_VALID) {
bool exec = pte_exec(*pte);
- tlb_batch_add_one(mm, vaddr, exec);
+ tlb_batch_add_one(mm, vaddr, exec, false);
}
pte++;
vaddr += PAGE_SIZE;
@@ -185,8 +195,9 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pte_t orig_pte = __pte(pmd_val(orig));
bool exec = pte_exec(orig_pte);
- tlb_batch_add_one(mm, addr, exec);
- tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec);
+ tlb_batch_add_one(mm, addr, exec, true);
+ tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec,
+ true);
} else {
tlb_batch_pmd_scan(mm, addr, orig);
}
--
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