Use the general page fault accounting by passing regs into handle_mm_fault(). It naturally solve the issue of multiple page fault accounting when page fault retry happened. To do this, we pass pt_regs pointer into __do_page_fault().
Unified · Split
| @@ -404,7 +404,8 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re · 403 unmodified lines | |||
| 404 | #define VM_FAULT_BADACCESS 0x020000 | 404 | #define VM_FAULT_BADACCESS 0x020000 |
| 405 | 405 | ||
| 406 | static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr, | 406 | static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr, |
| 407 | unsigned int mm_flags, unsigned long vm_flags) | 407 | unsigned int mm_flags, unsigned long vm_flags, |
| 408 | struct pt_regs *regs) | ||
| 408 | { | 409 | { |
| 409 | struct vm_area_struct *vma = find_vma(mm, addr); | 410 | struct vm_area_struct *vma = find_vma(mm, addr); |
| 410 | 411 | ||
| @@ -428,7 +429,7 @@ static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr, · 17 unmodified lines | |||
| 428 | */ | 429 | */ |
| 429 | if (!(vma->vm_flags & vm_flags)) | 430 | if (!(vma->vm_flags & vm_flags)) |
| 430 | return VM_FAULT_BADACCESS; | 431 | return VM_FAULT_BADACCESS; |
| 431 | return handle_mm_fault(vma, addr & PAGE_MASK, mm_flags, NULL); | 432 | return handle_mm_fault(vma, addr & PAGE_MASK, mm_flags, regs); |
| 432 | } | 433 | } |
| 433 | 434 | ||
| 434 | static bool is_el0_instruction_abort(unsigned int esr) | 435 | static bool is_el0_instruction_abort(unsigned int esr) |
| @@ -450,7 +451,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr, · 15 unmodified lines | |||
| 450 | { | 451 | { |
| 451 | const struct fault_info *inf; | 452 | const struct fault_info *inf; |
| 452 | struct mm_struct *mm = current->mm; | 453 | struct mm_struct *mm = current->mm; |
| 453 | vm_fault_t fault, major = 0; | 454 | vm_fault_t fault; |
| 454 | unsigned long vm_flags = VM_ACCESS_FLAGS; | 455 | unsigned long vm_flags = VM_ACCESS_FLAGS; |
| 455 | unsigned int mm_flags = FAULT_FLAG_DEFAULT; | 456 | unsigned int mm_flags = FAULT_FLAG_DEFAULT; |
| 456 | 457 | ||
| @@ -516,8 +517,7 @@ retry: · 59 unmodified lines | |||
| 516 | #endif | 517 | #endif |
| 517 | } | 518 | } |
| 518 | 519 | ||
| 519 | fault = __do_page_fault(mm, addr, mm_flags, vm_flags); | 520 | fault = __do_page_fault(mm, addr, mm_flags, vm_flags, regs); |
| 520 | major |= fault & VM_FAULT_MAJOR; | ||
| 521 | 521 | ||
| 522 | /* Quick path to respond to signals */ | 522 | /* Quick path to respond to signals */ |
| 523 | if (fault_signal_pending(fault, regs)) { | 523 | if (fault_signal_pending(fault, regs)) { |
| @@ -538,25 +538,8 @@ retry: · 14 unmodified lines | |||
| 538 | * Handle the "normal" (no error) case first. | 538 | * Handle the "normal" (no error) case first. |
| 539 | */ | 539 | */ |
| 540 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | | 540 | if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | |
| 541 | VM_FAULT_BADACCESS)))) { | 541 | VM_FAULT_BADACCESS)))) |
| 542 | /* | ||
| 543 | * Major/minor page fault accounting is only done | ||
| 544 | * once. If we go through a retry, it is extremely | ||
| 545 | * likely that the page will be found in page cache at | ||
| 546 | * that point. | ||
| 547 | */ | ||
| 548 | if (major) { | ||
| 549 | current->maj_flt++; | ||
| 550 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs, | ||
| 551 | addr); | ||
| 552 | } else { | ||
| 553 | current->min_flt++; | ||
| 554 | perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs, | ||
| 555 | addr); | ||
| 556 | } | ||
| 557 | |||
| 558 | return 0; | 542 | return 0; |
| 559 | } | ||
| 560 | 543 | ||
| 561 | /* | 544 | /* |
| 562 | * If we are in kernel mode at this point, we have no context to | 545 | * If we are in kernel mode at this point, we have no context to |