[patch 093/155] sh/mm: use helper fault_signal_pending()

[Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>]

From: Peter Xu <peterx@xxxxxxxxxx>
Subject: sh/mm: use helper fault_signal_pending()

Let SH to use the new fault_signal_pending() helper.  Here we'll need to
move the up_read() out because that's actually needed as long as !RETRY
cases.  At the meantime we can drop all the rest of up_read()s now (which
seems to be cleaner).

Link: http://lkml.kernel.org/r/20200220160226.9550-1-peterx@xxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Tested-by: Brian Geffon <bgeffon@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Bobby Powers <bobbypowers@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Denis Plotnikov <dplotnikov@xxxxxxxxxxxxx>
Cc: "Dr . David Alan Gilbert" <dgilbert@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Jerome Glisse <jglisse@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: "Kirill A . Shutemov" <kirill@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Martin Cracauer <cracauer@xxxxxxxx>
Cc: Marty McFadden <mcfadden8@xxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Maya Gokhale <gokhale2@xxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 arch/sh/mm/fault.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/arch/sh/mm/fault.c~sh-mm-use-helper-fault_signal_pending
+++ a/arch/sh/mm/fault.c
@@ -302,25 +302,25 @@ mm_fault_error(struct pt_regs *regs, uns
 	 * Pagefault was interrupted by SIGKILL. We have no reason to
 	 * continue pagefault.
 	 */
-	if (fatal_signal_pending(current)) {
-		if (!(fault & VM_FAULT_RETRY))
-			up_read(&current->mm->mmap_sem);
+	if (fault_signal_pending(fault, regs)) {
 		if (!user_mode(regs))
 			no_context(regs, error_code, address);
 		return 1;
 	}
 
+	/* Release mmap_sem first if necessary */
+	if (!(fault & VM_FAULT_RETRY))
+		up_read(&current->mm->mmap_sem);
+
 	if (!(fault & VM_FAULT_ERROR))
 		return 0;
 
 	if (fault & VM_FAULT_OOM) {
 		/* Kernel mode? Handle exceptions or die: */
 		if (!user_mode(regs)) {
-			up_read(&current->mm->mmap_sem);
 			no_context(regs, error_code, address);
 			return 1;
 		}
-		up_read(&current->mm->mmap_sem);
 
 		/*
 		 * We ran out of memory, call the OOM killer, and return the
_