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: Geert Uytterhoeven <ge...@linux-m68k.org>
CC: linux-m...@lists.linux-m68k.org
Signed-off-by: Peter Xu <pet...@redhat.com>
---
 arch/m68k/mm/fault.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/arch/m68k/mm/fault.c b/arch/m68k/mm/fault.c
index 08b35a318ebe..795f483b1050 100644
--- a/arch/m68k/mm/fault.c
+++ b/arch/m68k/mm/fault.c
@@ -12,6 +12,7 @@
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/uaccess.h>
+#include <linux/perf_event.h>
 
 #include <asm/setup.h>
 #include <asm/traps.h>
@@ -84,6 +85,8 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
 
        if (user_mode(regs))
                flags |= FAULT_FLAG_USER;
+
+       perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
        mmap_read_lock(mm);
 
@@ -134,7 +137,7 @@ int 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);
        pr_debug("handle_mm_fault returns %x\n", fault);
 
        if (fault_signal_pending(fault, regs))
@@ -150,16 +153,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long 
address,
                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)
-                       current->maj_flt++;
-               else
-                       current->min_flt++;
                if (fault & VM_FAULT_RETRY) {
                        flags |= FAULT_FLAG_TRIED;
 
-- 
2.26.2

Reply via email to