[PATCH 20/25] mm/sh: Use mm_fault_accounting()

Peter Xu
2020-06-15T22:23:06Z

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

Avoid doing page fault accounting multiple times if the page fault is retried.

CC: Yoshinori Sato <ysato@users.sourceforge.jp>
CC: Rich Felker <dalias@libc.org>
CC: linux-sh@vger.kernel.org
Signed-off-by: Peter Xu <peterx@redhat.com>
---
arch/sh/mm/fault.c | 15 +++------------
1 file changed, 3 insertions(+), 12 deletions(-)

diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index 5f23d7907597..06b232973488 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -379,7 +379,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
struct task_struct *tsk;
struct mm_struct *mm;
struct vm_area_struct * vma;
- vm_fault_t fault;
+ vm_fault_t fault, major = 0;
unsigned int flags = FAULT_FLAG_DEFAULT;

tsk = current;
@@ -412,8 +412,6 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
if ((regs->sr & SR_IMASK) != SR_IMASK)
local_irq_enable();

- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
-
/*
* If we're in an interrupt, have no user context or are running
* with pagefaults disabled then we must not take the fault:
@@ -465,21 +463,13 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
* the fault.
*/
fault = handle_mm_fault(vma, address, flags);
+ major |= fault & VM_FAULT_MAJOR;

if (unlikely(fault & (VM_FAULT_RETRY | VM_FAULT_ERROR)))
if (mm_fault_error(regs, error_code, address, fault))
return;

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, address);
- } else {
- tsk->min_flt++;
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1,
- regs, address);
- }
if (fault & VM_FAULT_RETRY) {
flags |= FAULT_FLAG_TRIED;

@@ -493,4 +483,5 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
}

up_read(&mm->mmap_sem);
+ mm_fault_accounting(tsk, regs, address, major);
}
--
2.26.2