Hi Andrew,
Can you please accept this patch into linux-next ?
I have Chris Zankel's approval as below..
Thanks,
Kautuk.
On Wed, Jun 13, 2012 at 3:05 AM, Chris Zankel <[email protected]> wrote:
> Hi Kautuk,
>
> Patch looks fine, so:
>
> Acked-by: Chris Zankel <[email protected]>
>
> Thanks,
> -Chris
>
>
> On 6/12/12 8:54 AM, Kautuk Consul wrote:
>>
>> Hi,
>>
>> Could you please review this patch ?
>>
>> Many archs have accepted this patch, so I think maybe this is okay. :)
>>
>> Thanks,
>> Kautuk.
>>
>> On Sat, Mar 31, 2012 at 5:35 PM, Kautuk Consul<[email protected]>
>> ?wrote:
>>>
>>> Commit d065bd810b6deb67d4897a14bfe21f8eb526ba99
>>> (mm: retry page fault when blocking on disk transfer) and
>>> commit 37b23e0525d393d48a7d59f870b3bc061a30ccdb
>>> (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 xtensa.
>>>
>>> Signed-off-by: Kautuk Consul<[email protected]>
>>> ---
>>> ?arch/xtensa/mm/fault.c | ? 29 ++++++++++++++++++++++++-----
>>> ?1 files changed, 24 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c
>>> index b17885a..5a74c53 100644
>>> --- a/arch/xtensa/mm/fault.c
>>> +++ b/arch/xtensa/mm/fault.c
>>> @@ -44,6 +44,7 @@ void do_page_fault(struct pt_regs *regs)
>>>
>>> ? ? ? ?int is_write, is_exec;
>>> ? ? ? ?int fault;
>>> + ? ? ? unsigned int flags = FAULT_FLAG_ALLOW_RETRY |
>>> FAULT_FLAG_KILLABLE;
>>>
>>> ? ? ? ?info.si_code = SEGV_MAPERR;
>>>
>>> @@ -71,6 +72,7 @@ void do_page_fault(struct pt_regs *regs)
>>> ? ? ? ? ? ? ? address, exccause, regs->pc, is_write? "w":"", is_exec?
>>> "x":"");
>>> ?#endif
>>>
>>> +retry:
>>> ? ? ? ?down_read(&mm->mmap_sem);
>>> ? ? ? ?vma = find_vma(mm, address);
>>>
>>> @@ -93,6 +95,7 @@ good_area:
>>> ? ? ? ?if (is_write) {
>>> ? ? ? ? ? ? ? ?if (!(vma->vm_flags& ?VM_WRITE))
>>>
>>> ? ? ? ? ? ? ? ? ? ? ? ?goto bad_area;
>>> + ? ? ? ? ? ? ? flags |= FAULT_FLAG_WRITE;
>>> ? ? ? ?} else if (is_exec) {
>>> ? ? ? ? ? ? ? ?if (!(vma->vm_flags& ?VM_EXEC))
>>>
>>> ? ? ? ? ? ? ? ? ? ? ? ?goto bad_area;
>>> @@ -104,7 +107,11 @@ good_area:
>>> ? ? ? ? * make sure we exit gracefully rather than endlessly redo
>>> ? ? ? ? * the fault.
>>> ? ? ? ? */
>>> - ? ? ? fault = handle_mm_fault(mm, vma, address, is_write ?
>>> FAULT_FLAG_WRITE : 0);
>>> + ? ? ? fault = handle_mm_fault(mm, vma, address, flags);
>>> +
>>> + ? ? ? if ((fault& ?VM_FAULT_RETRY)&& ?fatal_signal_pending(current))
>>>
>>> + ? ? ? ? ? ? ? return;
>>> +
>>> ? ? ? ?if (unlikely(fault& ?VM_FAULT_ERROR)) {
>>> ? ? ? ? ? ? ? ?if (fault& ?VM_FAULT_OOM)
>>>
>>> ? ? ? ? ? ? ? ? ? ? ? ?goto out_of_memory;
>>> @@ -112,10 +119,22 @@ good_area:
>>> ? ? ? ? ? ? ? ? ? ? ? ?goto do_sigbus;
>>> ? ? ? ? ? ? ? ?BUG();
>>> ? ? ? ?}
>>> - ? ? ? if (fault& ?VM_FAULT_MAJOR)
>>>
>>> - ? ? ? ? ? ? ? current->maj_flt++;
>>> - ? ? ? else
>>> - ? ? ? ? ? ? ? current->min_flt++;
>>> + ? ? ? 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;
>>> --
>>> 1.7.5.4
>>>
>