| Message ID | 1332775997-2197-1-git-send-email-consul.kautuk@gmail.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
On Mon, 2012-03-26 at 11:33 -0400, Kautuk Consul wrote: > diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c > index 504c062..8322962 100644 > --- a/arch/sparc/mm/fault_64.c > +++ b/arch/sparc/mm/fault_64.c > @@ -279,6 +279,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) > unsigned int insn = 0; > int si_code, fault_code, fault; > unsigned long address, mm_rss; > + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; > > fault_code = get_thread_fault_code(); > [] > @@ -423,7 +426,13 @@ good_area: > goto bad_area; > } > > - fault = handle_mm_fault(mm, vma, address, (fault_code & FAULT_CODE_WRITE) ? FAULT_FLAG_WRITE : 0); > + fault = handle_mm_fault(mm, vma, address, > + flags | ((fault_code & FAULT_CODE_WRITE) ? > + FAULT_FLAG_WRITE : 0); A bit redundant and very poor style argument alignment Make sure your tab indentation is set to 8. fault = handle_mm_fault(mm, vma, address, flags | (fault_code & FAULT_CODE_WRITE)); though perhaps fault_code could be unsigned and perhaps you could use the same style initializer for fault_code as patch 19/20. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Okay, I have sent both patches with tab-space as 8 characters and set the multiline C statements after the preceding line's paranthesis. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Kautuk Consul <consul.kautuk@gmail.com> Date: Mon, 26 Mar 2012 11:33:17 -0400 > + fault = handle_mm_fault(mm, vma, address, > + flags | ((fault_code & FAULT_CODE_WRITE) ? > + FAULT_FLAG_WRITE : 0); This is so shockingly gross I'm at a loss for words. Why are you tabbing this crap all the way into outer-space? Make the "flags | ..." line up with the first column after the openning parenthesis of "handle_mm_fault(". > + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, > + 1, regs, address); Same problem. > + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, > + 1, regs, address); Same problem. You're making the coding style worse each iteration, not better. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c index 504c062..8322962 100644 --- a/arch/sparc/mm/fault_64.c +++ b/arch/sparc/mm/fault_64.c @@ -279,6 +279,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) unsigned int insn = 0; int si_code, fault_code, fault; unsigned long address, mm_rss; + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; fault_code = get_thread_fault_code(); @@ -333,6 +334,8 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) insn = get_fault_insn(regs, insn); goto handle_kernel_fault; } + +retry: down_read(&mm->mmap_sem); } @@ -423,7 +426,13 @@ good_area: goto bad_area; } - fault = handle_mm_fault(mm, vma, address, (fault_code & FAULT_CODE_WRITE) ? FAULT_FLAG_WRITE : 0); + fault = handle_mm_fault(mm, vma, address, + flags | ((fault_code & FAULT_CODE_WRITE) ? + FAULT_FLAG_WRITE : 0); + + 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; @@ -431,12 +440,27 @@ good_area: goto do_sigbus; BUG(); } - if (fault & VM_FAULT_MAJOR) { - current->maj_flt++; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs, address); - } else { - current->min_flt++; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs, address); + + if (flags & FAULT_FLAG_ALLOW_RETRY) { + if (fault & VM_FAULT_MAJOR) { + current->maj_flt++; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, + 1, regs, address); + } else { + current->min_flt++; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, + 1, regs, address); + } + 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);
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 64-bit sparc. Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com> --- arch/sparc/mm/fault_64.c | 38 +++++++++++++++++++++++++++++++------- 1 files changed, 31 insertions(+), 7 deletions(-)