[PATCH] powerpc/32s: Don't flush all TLBs when flushing one page

From: Christophe Leroy
Date: Fri Jan 31 2020 - 10:37:37 EST


When flushing a range, the flushing function flushes all TLBs.

When the range is a single page, do a page flush instead.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/mm/book3s32/tlb.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/mm/book3s32/tlb.c b/arch/powerpc/mm/book3s32/tlb.c
index 2fcd321040ff..8e0089065a7e 100644
--- a/arch/powerpc/mm/book3s32/tlb.c
+++ b/arch/powerpc/mm/book3s32/tlb.c
@@ -79,14 +79,17 @@ static void flush_range(struct mm_struct *mm, unsigned long start,
int count;
unsigned int ctx = mm->context.id;

+ start &= PAGE_MASK;
+ end = (end - 1) | ~PAGE_MASK;
if (!Hash) {
- _tlbia();
+ if (end - start == PAGE_SIZE)
+ _tlbie(start);
+ else
+ _tlbia();
return;
}
- start &= PAGE_MASK;
if (start >= end)
return;
- end = (end - 1) | ~PAGE_MASK;
pmd = pmd_offset(pud_offset(pgd_offset(mm, start), start), start);
for (;;) {
pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1;
--
2.25.0