| Message ID | 20240403083805.1818160-7-wangkefeng.wang@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | arch/mm/fault: accelerate pagefault when badaccess | expand |
On Wed, Apr 03, 2024 at 04:38:04PM +0800, Kefeng Wang wrote: > The vm_flags of vma already checked under per-VMA lock, if it is a > bad access, directly handle error, no need to retry with mmap_lock > again. Since the page faut is handled under per-VMA lock, count it > as a vma lock event with VMA_LOCK_SUCCESS. > > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> > --- > arch/s390/mm/fault.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c > index c421dd44ffbe..162ca2576fd4 100644 > --- a/arch/s390/mm/fault.c > +++ b/arch/s390/mm/fault.c > @@ -325,7 +325,8 @@ static void do_exception(struct pt_regs *regs, int access) > goto lock_mmap; > if (!(vma->vm_flags & access)) { > vma_end_read(vma); > - goto lock_mmap; > + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); > + return handle_fault_error_nolock(regs, SEGV_ACCERR); Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index c421dd44ffbe..162ca2576fd4 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -325,7 +325,8 @@ static void do_exception(struct pt_regs *regs, int access) goto lock_mmap; if (!(vma->vm_flags & access)) { vma_end_read(vma); - goto lock_mmap; + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + return handle_fault_error_nolock(regs, SEGV_ACCERR); } fault = handle_mm_fault(vma, address, flags | FAULT_FLAG_VMA_LOCK, regs); if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED)))
The vm_flags of vma already checked under per-VMA lock, if it is a bad access, directly handle error, no need to retry with mmap_lock again. Since the page faut is handled under per-VMA lock, count it as a vma lock event with VMA_LOCK_SUCCESS. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- arch/s390/mm/fault.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)