[PATCH RESEND v6 05/16] arc/mm: Use helper fault_signal_pending()

From: Peter Xu <peterx@redhat.com>
To: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Cc: Peter Xu <peterx@redhat.com>, Martin Cracauer <cracauer@cons.org>,
	Mike Rapoport <rppt@linux.vnet.ibm.com>,
	Hugh Dickins <hughd@google.com>,
	Jerome Glisse <jglisse@redhat.com>,
	"Kirill A . Shutemov" <kirill@shutemov.name>,
	Matthew Wilcox <willy@infradead.org>,
	Pavel Emelyanov <xemul@virtuozzo.com>,
	Brian Geffon <bgeffon@google.com>,
	Maya Gokhale <gokhale2@llnl.gov>,
	Denis Plotnikov <dplotnikov@virtuozzo.com>,
	Andrea Arcangeli <aarcange@redhat.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	"Dr . David Alan Gilbert" <dgilbert@redhat.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	Marty McFadden <mcfadden8@llnl.gov>,
	David Hildenbrand <david@redhat.com>,
	Bobby Powers <bobbypowers@gmail.com>,
	Mel Gorman <mgorman@suse.de>
Subject: [PATCH RESEND v6 05/16] arc/mm: Use helper fault_signal_pending()
Date: Thu, 20 Feb 2020 10:58:43 -0500	[thread overview]
Message-ID: <20200220155843.9172-1-peterx@redhat.com> (raw)
In-Reply-To: <20200220155353.8676-1-peterx@redhat.com>

Let ARC to use the new helper fault_signal_pending() by moving the
signal check out of the retry logic as standalone.  This should also
helps to simplify the code a bit.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 arch/arc/mm/fault.c | 34 +++++++++++++---------------------
 1 file changed, 13 insertions(+), 21 deletions(-)

diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index fb86bc3e9b35..6eb821a59b49 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -133,29 +133,21 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
 
 	fault = handle_mm_fault(vma, address, flags);
 
+	/* Quick path to respond to signals */
+	if (fault_signal_pending(fault, regs)) {
+		if (!user_mode(regs))
+			goto no_context;
+		return;
+	}
+
 	/*
-	 * Fault retry nuances
+	 * Fault retry nuances, mmap_sem already relinquished by core mm
 	 */
-	if (unlikely(fault & VM_FAULT_RETRY)) {
-
-		/*
-		 * If fault needs to be retried, handle any pending signals
-		 * first (by returning to user mode).
-		 * mmap_sem already relinquished by core mm for RETRY case
-		 */
-		if (fatal_signal_pending(current)) {
-			if (!user_mode(regs))
-				goto no_context;
-			return;
-		}
-		/*
-		 * retry state machine
-		 */
-		if (flags & FAULT_FLAG_ALLOW_RETRY) {
-			flags &= ~FAULT_FLAG_ALLOW_RETRY;
-			flags |= FAULT_FLAG_TRIED;
-			goto retry;
-		}
+	if (unlikely((fault & VM_FAULT_RETRY) &&
+		     (flags & FAULT_FLAG_ALLOW_RETRY))) {
+		flags &= ~FAULT_FLAG_ALLOW_RETRY;
+		flags |= FAULT_FLAG_TRIED;
+		goto retry;
 	}
 
 bad_area:
-- 
2.24.1

