[PATCH 04/25] mm/arc: Use mm_fault_accounting()

From: Peter Xu
Date: Mon Jun 15 2020 - 18:16:30 EST


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

The functional change here is that now we take the whole page fault as a major
fault as long as any of the retried page fault is a major fault. Previously we
only considered the last fault.

CC: Vineet Gupta <vgupta@xxxxxxxxxxxx>
CC: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/arc/mm/fault.c | 15 +++------------
1 file changed, 3 insertions(+), 12 deletions(-)

diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index 92b339c7adba..bc89d4b9c59d 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -72,6 +72,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
int sig, si_code = SEGV_MAPERR;
unsigned int write = 0, exec = 0, mask;
vm_fault_t fault = VM_FAULT_SIGSEGV; /* handle_mm_fault() output */
+ vm_fault_t major = 0;
unsigned int flags; /* handle_mm_fault() input */

/*
@@ -132,6 +133,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
}

fault = handle_mm_fault(vma, address, flags);
+ major |= fault & VM_FAULT_MAJOR;

/* Quick path to respond to signals */
if (fault_signal_pending(fault, regs)) {
@@ -156,20 +158,9 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
* Major/minor page fault accounting
* (in case of retry we only land here once)
*/
- perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
-
if (likely(!(fault & VM_FAULT_ERROR))) {
- 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);
- }
-
/* Normal return path: fault Handled Gracefully */
+ mm_fault_accounting(tsk, regs, address, major);
return;
}

--
2.26.2