Hi Kautuk, sorry for the very late reply! Anyway, the patch seems OK, and we will include it in the next parisc kernel. THANKS!!! Helge @Dave, James: - This is the patch "11" in Dave's package... - Kautuk even sent a testcase: http://marc.info/?l=linux-mm&m=133319623304492&w=2 On 06/12/2012 05:55 PM, Kautuk Consul wrote: > Hi, > > Can you please review this patch ? > > Many archs have actually accepted this change so I think maybe this is okay. :) > > Thanks, > Kautuk. > > On Sat, Mar 31, 2012 at 5:36 PM, Kautuk Consul <consul.kautuk@xxxxxxxxx> 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. >> >> Signed-off-by: Kautuk Consul <consul.kautuk@xxxxxxxxx> >> --- >> arch/parisc/mm/fault.c | 29 ++++++++++++++++++++++++----- >> 1 files changed, 24 insertions(+), 5 deletions(-) >> >> diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c >> index 18162ce..bd66ed6 100644 >> --- a/arch/parisc/mm/fault.c >> +++ b/arch/parisc/mm/fault.c >> @@ -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 +221,22 @@ good_area: >> goto bad_area; >> 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 >> -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
