diff options
| author |   Kautuk Consul <consul.kautuk@gmail.com> | 2012-03-31 08:05:39 -0400 |
|---|---|---|
| committer |   Chris Metcalf <cmetcalf@tilera.com> | 2012-05-25 12:48:29 -0400 |
| commit | 4ce6bea220f1a40aba928bd5624ada833ee1c52b (patch) | |
| tree | 39850830736916febb5b97741788d17955c9d5af /arch | |
| parent | arch/tile: add descriptive text if the kernel reports a bad trap (diff) | |
| download | linux-dev-4ce6bea220f1a40aba928bd5624ada833ee1c52b.tar.xz linux-dev-4ce6bea220f1a40aba928bd5624ada833ee1c52b.zip | |
tile/mm/fault.c: Port OOM changes to handle_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 tile.
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
[cmetcalf@tilera.com: initialize "flags" after "write" updated.]
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/tile/mm/fault.c | 32 |
1 files changed, 27 insertions, 5 deletions
diff --git a/arch/tile/mm/fault.c b/arch/tile/mm/fault.c index 54f18fc25ed0..84ce7abbf5af 100644 --- a/arch/tile/mm/fault.c +++ b/arch/tile/mm/fault.c @@ -273,11 +273,15 @@ static int handle_page_fault(struct pt_regs *regs, int si_code; int is_kernel_mode; pgd_t *pgd; + unsigned int flags; /* on TILE, protection faults are always writes */ if (!is_page_fault) write = 1; + flags = (FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | + (write ? FAULT_FLAG_WRITE : 0)); + is_kernel_mode = (EX1_PL(regs->ex1) != USER_PL); tsk = validate_current(); @@ -382,6 +386,8 @@ static int handle_page_fault(struct pt_regs *regs, vma = NULL; /* happy compiler */ goto bad_area_nosemaphore; } + +retry: down_read(&mm->mmap_sem); } @@ -429,7 +435,11 @@ good_area: * make sure we exit gracefully rather than endlessly redo * the fault. */ - fault = handle_mm_fault(mm, vma, address, write); + fault = handle_mm_fault(mm, vma, address, flags); + + if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) + return 0; + if (unlikely(fault & VM_FAULT_ERROR)) { if (fault & VM_FAULT_OOM) goto out_of_memory; @@ -437,10 +447,22 @@ good_area: 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; + } + } #if CHIP_HAS_TILE_DMA() || CHIP_HAS_SN_PROC() /* |