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| author | Kautuk Consul <consul.kautuk@gmail.com> | 2012-03-20 14:24:05 +0100 |
|---|---|---|
| committer | Jesper Nilsson <jespern@axis.com> | 2012-04-04 17:50:30 +0200 |
| commit | 4d5914d628360c607dc426ccb1acaf23909ac546 (patch) | |
| tree | 711cce67064eabd0d3347fb90ff80c55d59667ed | |
| parent | dfb73a071f0259ba81ceea7b7f312f63dd18c73c (diff) | |
| download | lwn-4d5914d628360c607dc426ccb1acaf23909ac546.tar.gz lwn-4d5914d628360c607dc426ccb1acaf23909ac546.zip | |
cris/mm/fault.c: Port OOM changes to do_page_fault
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 CRIS.
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
| -rw-r--r-- | arch/cris/mm/fault.c | 31 |
1 files changed, 26 insertions, 5 deletions
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c index b4760d86e1bb..45fd542cf173 100644 --- a/arch/cris/mm/fault.c +++ b/arch/cris/mm/fault.c @@ -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; |