[PATCH v5 14/25] mm/openrisc: Use general page fault accounting

[Peter Xu]

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.

Add the missing PERF_COUNT_SW_PAGE_FAULTS perf events too.  Note, the other two
perf events (PERF_COUNT_SW_PAGE_FAULTS_[MAJ|MIN]) were done in 
handle_mm_fault().

CC: Jonas Bonn <jo...@southpole.se>
CC: Stefan Kristiansson <stefan.kristians...@saunalahti.fi>
CC: Stafford Horne <sho...@gmail.com>
CC: openr...@lists.librecores.org
Acked-by: Stafford Horne <sho...@gmail.com>
Signed-off-by: Peter Xu <pet...@redhat.com>
---
 arch/openrisc/mm/fault.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/openrisc/mm/fault.c b/arch/openrisc/mm/fault.c
index 3daa491d1edb..ca97d9baab51 100644
--- a/arch/openrisc/mm/fault.c
+++ b/arch/openrisc/mm/fault.c
@@ -15,6 +15,7 @@
 #include <linux/interrupt.h>
 #include <linux/extable.h>
 #include <linux/sched/signal.h>
+#include <linux/perf_event.h>
 
 #include <linux/uaccess.h>
 #include <asm/siginfo.h>
@@ -103,6 +104,8 @@ asmlinkage void do_page_fault(struct pt_regs *regs, 
unsigned long address,
        if (in_interrupt() || !mm)
                goto no_context;
 
+       perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
+
 retry:
        mmap_read_lock(mm);
        vma = find_vma(mm, address);
@@ -159,7 +162,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, 
unsigned long address,
         * the fault.
         */
 
-       fault = handle_mm_fault(vma, address, flags, NULL);
+       fault = handle_mm_fault(vma, address, flags, regs);
 
        if (fault_signal_pending(fault, regs))
                return;
@@ -176,10 +179,6 @@ asmlinkage void do_page_fault(struct pt_regs *regs, 
unsigned long address,
 
        if (flags & FAULT_FLAG_ALLOW_RETRY) {
                /*RGD modeled on Cris */
-               if (fault & VM_FAULT_MAJOR)
-                       tsk->maj_flt++;
-               else
-                       tsk->min_flt++;
                if (fault & VM_FAULT_RETRY) {
                        flags |= FAULT_FLAG_TRIED;
 
-- 
2.26.2