[PATCH v2 07/23 fix] mips: update_mmu_cache() can replace __update_tlb(): fix

From: Hugh Dickins
Date: Fri Jun 09 2023 - 04:10:53 EST


I expect this to fix the
arch/mips/mm/tlb-r4k.c:300:16: warning: variable 'pmdp' set but not used
reported by the kernel test robot; but I am uncomfortable rearranging
lines in this tlb_probe_hazard() area, and would be glad for review and
testing by someone familiar with mips - thanks in advance!

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202306091304.cNVIspK0-lkp@xxxxxxxxx/
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
---
arch/mips/mm/tlb-r4k.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
index c96725d17cab..80fc90d8d2f1 100644
--- a/arch/mips/mm/tlb-r4k.c
+++ b/arch/mips/mm/tlb-r4k.c
@@ -293,11 +293,13 @@ void local_flush_tlb_one(unsigned long page)
void update_mmu_cache(struct vm_area_struct *vma,
unsigned long address, pte_t *ptep)
{
- unsigned long flags;
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
pgd_t *pgdp;
p4d_t *p4dp;
pud_t *pudp;
pmd_t *pmdp;
+#endif
+ unsigned long flags;
int idx, pid;

/*
@@ -316,15 +318,15 @@ void update_mmu_cache(struct vm_area_struct *vma,
pid = read_c0_entryhi() & cpu_asid_mask(&current_cpu_data);
write_c0_entryhi(address | pid);
}
- pgdp = pgd_offset(vma->vm_mm, address);
mtc0_tlbw_hazard();
tlb_probe();
tlb_probe_hazard();
+ idx = read_c0_index();
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
+ pgdp = pgd_offset(vma->vm_mm, address);
p4dp = p4d_offset(pgdp, address);
pudp = pud_offset(p4dp, address);
pmdp = pmd_offset(pudp, address);
- idx = read_c0_index();
-#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
/* this could be a huge page */
if (ptep == (pte_t *)pmdp) {
unsigned long lo;
--
2.35.3