[PATCH v4 17/26] mm/riscv: Use general page fault accounting

From: Peter Xu
Date: Tue Jun 30 2020 - 16:46:01 EST


Use the general page fault accounting by passing regs into handle_mm_fault().
It naturally solve the issue of multiple page fault accounting when page fault
retry happened.

CC: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
CC: Palmer Dabbelt <palmer@xxxxxxxxxxx>
CC: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
CC: linux-riscv@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/riscv/mm/fault.c | 16 +---------------
1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 50a952a68433..e72cec09d55b 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -110,7 +110,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
- fault = handle_mm_fault(vma, addr, flags, NULL);
+ fault = handle_mm_fault(vma, addr, flags, regs);

/*
* If we need to retry but a fatal signal is pending, handle the
@@ -128,21 +128,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
BUG();
}

- /*
- * Major/minor page fault accounting is only done on the
- * initial attempt. If we go through a retry, it is extremely
- * likely that the page will be found in page cache at that point.
- */
if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_MAJOR) {
- tsk->maj_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ,
- 1, regs, addr);
- } else {
- tsk->min_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN,
- 1, regs, addr);
- }
if (fault & VM_FAULT_RETRY) {
flags |= FAULT_FLAG_TRIED;

--
2.26.2