mm/parisc: use general page fault accounting

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().

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Link: http://lkml.kernel.org/r/20200707225021.200906-16-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index e32d069..4bfe2da 100644 (file)
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -18,6 +18,7 @@
 #include <linux/extable.h>
 #include <linux/uaccess.h>
 #include <linux/hugetlb.h>
+#include <linux/perf_event.h>
 
 #include <asm/traps.h>
 
@@ -281,6 +282,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
        acc_type = parisc_acctyp(code, regs->iir);
        if (acc_type & VM_WRITE)
                flags |= FAULT_FLAG_WRITE;
+       perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
        mmap_read_lock(mm);
        vma = find_vma_prev(mm, address, &prev_vma);
@@ -302,7 +304,7 @@ good_area:
         * fault.
         */
 
-       fault = handle_mm_fault(vma, address, flags, NULL);
+       fault = handle_mm_fault(vma, address, flags, regs);
 
        if (fault_signal_pending(fault, regs))
                return;
@@ -323,10 +325,6 @@ good_area:
                BUG();
        }
        if (flags & FAULT_FLAG_ALLOW_RETRY) {
-               if (fault & VM_FAULT_MAJOR)
-                       current->maj_flt++;
-               else
-                       current->min_flt++;
                if (fault & VM_FAULT_RETRY) {
                        /*
                         * No need to mmap_read_unlock(mm) as we would