From: Peter Xu <peterx@xxxxxxxxxx> Subject: 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. Link: http://lkml.kernel.org/r/20200220155927.9264-1-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/arm64/mm/fault.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) --- a/arch/arm64/mm/fault.c~arm64-mm-use-helper-fault_signal_pending +++ a/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. _