arm64/mm: use helper fault_signal_pending()

Let the arm64 fault handling to use the new fault_signal_pending() helper,
by moving the signal handling out of the retry logic.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220155927.9264-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 85566d3..6f4b69d 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -513,19 +513,14 @@ retry:
        fault = __do_page_fault(mm, addr, mm_flags, vm_flags);
        major |= fault & VM_FAULT_MAJOR;
 
-       if (fault & VM_FAULT_RETRY) {
-               /*
-                * If we need to retry but a fatal signal is pending,
-                * handle the signal first. We do not need to release
-                * the mmap_sem because it would already be released
-                * in __lock_page_or_retry in mm/filemap.c.
-                */
-               if (fatal_signal_pending(current)) {
-                       if (!user_mode(regs))
-                               goto no_context;
-                       return 0;
-               }
+       /* Quick path to respond to signals */
+       if (fault_signal_pending(fault, regs)) {
+               if (!user_mode(regs))
+                       goto no_context;
+               return 0;
+       }
 
+       if (fault & VM_FAULT_RETRY) {
                /*
                 * Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk of
                 * starvation.