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

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Commit d065bd810b
(mm: retry page fault when blocking on disk transfer) and
commit 37b23e0525
(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 CRIS.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
This commit is contained in:
Kautuk Consul 2012-03-20 14:24:05 +01:00 committed by Jesper Nilsson
parent dfb73a071f
commit 4d5914d628
1 changed files with 26 additions and 5 deletions
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31
arch/cris/mm/fault.c
View file

@ -58,6 +58,8 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
struct vm_area_struct * vma;
siginfo_t info;
int fault;
unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
((writeaccess & 1) ? FAULT_FLAG_WRITE : 0);
D(printk(KERN_DEBUG
"Page fault for %lX on %X at %lX, prot %d write %d\n",
@ -115,6 +117,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
if (in_atomic() || !mm)
goto no_context;
retry:
down_read(&mm->mmap_sem);
vma = find_vma(mm, address);
if (!vma)
@ -163,7 +166,11 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
* the fault.
*/
fault = handle_mm_fault(mm, vma, address, (writeaccess & 1) ? 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;
@ -171,10 +178,24 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
if (flags & FAULT_FLAG_ALLOW_RETRY) {
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->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;