arm64: mm: accelerate pagefault when VM_FAULT_BADACCESS

The vm_flags of vma already checked under per-VMA lock, if it is a bad
access, directly set fault to VM_FAULT_BADACCESS and handle error, no need
to retry with mmap_lock again, the latency time reduces 34% in 'lat_sig -P
1 prot lat_sig' from lmbench testcase.

Since the page fault is handled under per-VMA lock, count it as a vma lock
event with VMA_LOCK_SUCCESS.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kefeng Wang <[email protected]>
Reviewed-by: Suren Baghdasaryan <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Cc: Albert Ou <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Gerald Schaefer <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Russell King <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions