| Message ID | 20240402075142.196265-4-wangkefeng.wang@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arch/mm/fault: accelerate pagefault when badaccess | expand |
On Tue, Apr 2, 2024 at 12:53 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote: > > 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, > so no need to lock_mm_and_find_vma() and check vm_flags again. > > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> > --- > arch/arm/mm/fault.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c > index 439dc6a26bb9..5c4b417e24f9 100644 > --- a/arch/arm/mm/fault.c > +++ b/arch/arm/mm/fault.c > @@ -294,7 +294,9 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) > > if (!(vma->vm_flags & vm_flags)) { > vma_end_read(vma); > - goto lock_mmap; > + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); > + fault = VM_FAULT_BADACCESS; > + goto bad_area; > } > fault = handle_mm_fault(vma, addr, flags | FAULT_FLAG_VMA_LOCK, regs); > if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) > -- > 2.27.0 >
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 439dc6a26bb9..5c4b417e24f9 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -294,7 +294,9 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) if (!(vma->vm_flags & vm_flags)) { vma_end_read(vma); - goto lock_mmap; + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + fault = VM_FAULT_BADACCESS; + goto bad_area; } fault = handle_mm_fault(vma, addr, 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 set fault to VM_FAULT_BADACCESS and handle error, so no need to lock_mm_and_find_vma() and check vm_flags again. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> --- arch/arm/mm/fault.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)