Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 38057477 authored by Kautuk Consul's avatar Kautuk Consul Committed by Helge Deller
Browse files

parisc/mm/fault.c: Port OOM changes to do_page_fault 



Commit d065bd81
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e05
(x86,mm: make pagefault killable)

The above commits introduced changes into the x86 pagefault handler
for making the page fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial
during OOM killer invocation.

Port these changes to parisc.

Signed-off-by: default avatarKautuk Consul <consul.kautuk@gmail.com>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 45b6eff2

arch/parisc/mm/fault.c

+25 −5
Original line number Diff line number Diff line
@@ -175,10 +175,12 @@ void do_page_fault(struct pt_regs *regs, unsigned long code, 
	struct mm_struct *mm = tsk->mm;

	unsigned long acc_type;

	int fault;

	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;



	if (in_atomic() || !mm)

		goto no_context;



retry:

	down_read(&mm->mmap_sem);

	vma = find_vma_prev(mm, address, &prev_vma);

	if (!vma || address < vma->vm_start)
@@ -201,7 +203,12 @@ good_area: 
	 * fault.

	 */



	fault = handle_mm_fault(mm, vma, address, (acc_type & VM_WRITE) ? FAULT_FLAG_WRITE : 0);

	fault = handle_mm_fault(mm, vma, address,

			flags | ((acc_type & VM_WRITE) ? FAULT_FLAG_WRITE : 0));



	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))

		return;



	if (unlikely(fault & VM_FAULT_ERROR)) {

		/*

		 * We hit a shared mapping outside of the file, or some
@@ -214,10 +221,23 @@ good_area: 
			goto bad_area;

		BUG();

	}

	if (flags & FAULT_FLAG_ALLOW_RETRY) {

		if (fault & VM_FAULT_MAJOR)

			current->maj_flt++;

		else

			current->min_flt++;

		if (fault & VM_FAULT_RETRY) {

			flags &= ~FAULT_FLAG_ALLOW_RETRY;



			/*

			 * No need to up_read(&mm->mmap_sem) as we would

			 * have already released it in __lock_page_or_retry

			 * in mm/filemap.c.

			 */



			goto retry;

		}

	}

	up_read(&mm->mmap_sem);

	return;