[PATCH 12/25] mm/mips: Use mm_fault_accounting()

From: Peter Xu
Date: Mon Jun 15 2020 - 18:16:41 EST


Use the new mm_fault_accounting() helper for page fault accounting.

Avoid doing page fault accounting multiple times if the page fault is retried.
Since at it, move the accouting out of mmap_sem because not needed.

CC: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
CC: linux-mips@xxxxxxxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/mips/mm/fault.c | 14 +++-----------
1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index f8d62cd83b36..0b937fb12614 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -43,7 +43,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
struct mm_struct *mm = tsk->mm;
const int field = sizeof(unsigned long) * 2;
int si_code;
- vm_fault_t fault;
+ vm_fault_t fault, major = 0;
unsigned int flags = FAULT_FLAG_DEFAULT;

static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10);
@@ -153,11 +153,11 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
* the fault.
*/
fault = handle_mm_fault(vma, address, flags);
+ major |= fault & VM_FAULT_MAJOR;

if (fault_signal_pending(fault, regs))
return;

- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
@@ -168,15 +168,6 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
BUG();
}
if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (fault & VM_FAULT_MAJOR) {
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1,
- regs, address);
- tsk->maj_flt++;
- } else {
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1,
- regs, address);
- tsk->min_flt++;
- }
if (fault & VM_FAULT_RETRY) {
flags |= FAULT_FLAG_TRIED;

@@ -191,6 +182,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
}

up_read(&mm->mmap_sem);
+ mm_fault_accounting(tsk, regs, address, major);
return;

/*
--
2.26.2