Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753638Ab2EHJyP (ORCPT ); Tue, 8 May 2012 05:54:15 -0400 Received: from mail.southpole.se ([193.12.106.18]:56640 "EHLO mail.southpole.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753197Ab2EHJyH (ORCPT ); Tue, 8 May 2012 05:54:07 -0400 From: Jonas Bonn To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Cc: Kautuk Consul , "Mohd. Faris" , Jonas Bonn Subject: [PATCH 3/6] openrisc/mm/fault.c: Port OOM changes to do_page_fault Date: Tue, 8 May 2012 11:54:02 +0200 Message-Id: <1336470845-13859-4-git-send-email-jonas@southpole.se> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <1336470845-13859-1-git-send-email-jonas@southpole.se> References: <1336470845-13859-1-git-send-email-jonas@southpole.se> X-Assp-Version: 2.1.1(11364) on assp.southpole.se X-Assp-Client-SSL: yes X-Assp-ID: assp.southpole.se 70843-07466 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2800 Lines: 102 From: Kautuk Consul 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 Signed-off-by: Kautuk Consul Signed-off-by: Jonas Bonn --- arch/openrisc/mm/fault.c | 32 ++++++++++++++++++++++++++------ 1 files changed, 26 insertions(+), 6 deletions(-) diff --git a/arch/openrisc/mm/fault.c b/arch/openrisc/mm/fault.c index a5dce82..40f850e 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; -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/