aboutsummaryrefslogtreecommitdiff
path: root/arch/openrisc/mm
diff options
context:
space:
mode:
authorKautuk Consul <consul.kautuk@gmail.com>2012-03-31 08:00:51 -0400
committerJonas Bonn <jonas@southpole.se>2012-05-08 11:43:20 +0200
commit4971f2bdb746e6cc8423ea60f99694884f6052c5 (patch)
tree9ad37df4ecc0d57b478f3f4f22b775bd4f848da8 /arch/openrisc/mm
parentad188f955a79f5501b0cd5bde2b0621b3c78044a (diff)
downloadlinux-4971f2bdb746e6cc8423ea60f99694884f6052c5.tar.gz
openrisc/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 openrisc. Signed-off-by: Mohd. Faris <mohdfarisq2010@gmail.com> Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com> Signed-off-by: Jonas Bonn <jonas@southpole.se>
Diffstat (limited to 'arch/openrisc/mm')
-rw-r--r--arch/openrisc/mm/fault.c32
1 files changed, 26 insertions, 6 deletions
diff --git a/arch/openrisc/mm/fault.c b/arch/openrisc/mm/fault.c
index a5dce82f864..40f850e9766 100644
--- a/arch/openrisc/mm/fault.c
+++ b/arch/openrisc/mm/fault.c
@@ -54,6 +54,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long address,
struct vm_area_struct *vma;
siginfo_t info;
int fault;
+ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
tsk = current;
@@ -105,6 +106,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long address,
if (in_interrupt() || !mm)
goto no_context;
+retry:
down_read(&mm->mmap_sem);
vma = find_vma(mm, address);
@@ -143,6 +145,7 @@ good_area:
if (write_acc) {
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
+ flags |= FAULT_FLAG_WRITE;
} else {
/* not present */
if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
@@ -159,7 +162,11 @@ good_area:
* the fault.
*/
- fault = handle_mm_fault(mm, vma, address, write_acc);
+ 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;
@@ -167,11 +174,24 @@ good_area:
goto do_sigbus;
BUG();
}
- /*RGD modeled on Cris */
- if (fault & VM_FAULT_MAJOR)
- tsk->maj_flt++;
- else
- tsk->min_flt++;
+
+ if (flags & FAULT_FLAG_ALLOW_RETRY) {
+ /*RGD modeled on Cris */
+ 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;