The patch titled Subject: mm/arc: use general page fault accounting has been added to the -mm tree. Its filename is mm-arc-use-general-page-fault-accounting.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-arc-use-general-page-fault-accounting.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-arc-use-general-page-fault-accounting.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Peter Xu <peterx@xxxxxxxxxx> Subject: mm/arc: use general page fault accounting 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. Fix PERF_COUNT_SW_PAGE_FAULTS perf event manually for page fault retries, by moving it before taking mmap_sem. Link: http://lkml.kernel.org/r/20200707225021.200906-4-peterx@xxxxxxxxxx Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arc/mm/fault.c | 18 +++--------------- 1 file changed, 3 insertions(+), 15 deletions(-) --- a/arch/arc/mm/fault.c~mm-arc-use-general-page-fault-accounting +++ a/arch/arc/mm/fault.c @@ -105,6 +105,7 @@ void do_page_fault(unsigned long address if (write) flags |= FAULT_FLAG_WRITE; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); retry: mmap_read_lock(mm); @@ -130,7 +131,7 @@ retry: goto bad_area; } - fault = handle_mm_fault(vma, address, flags, NULL); + fault = handle_mm_fault(vma, address, flags, regs); /* Quick path to respond to signals */ if (fault_signal_pending(fault, regs)) { @@ -155,22 +156,9 @@ bad_area: * Major/minor page fault accounting * (in case of retry we only land here once) */ - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); - - if (likely(!(fault & VM_FAULT_ERROR))) { - if (fault & VM_FAULT_MAJOR) { - tsk->maj_flt++; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, - regs, address); - } else { - tsk->min_flt++; - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, - regs, address); - } - + if (likely(!(fault & VM_FAULT_ERROR))) /* Normal return path: fault Handled Gracefully */ return; - } if (!user_mode(regs)) goto no_context; _ Patches currently in -mm which might be from peterx@xxxxxxxxxx are mm-do-page-fault-accounting-in-handle_mm_fault.patch mm-alpha-use-general-page-fault-accounting.patch mm-arc-use-general-page-fault-accounting.patch mm-arm-use-general-page-fault-accounting.patch mm-arm64-use-general-page-fault-accounting.patch mm-csky-use-general-page-fault-accounting.patch mm-hexagon-use-general-page-fault-accounting.patch mm-ia64-use-general-page-fault-accounting.patch mm-m68k-use-general-page-fault-accounting.patch mm-microblaze-use-general-page-fault-accounting.patch mm-mips-use-general-page-fault-accounting.patch mm-nds32-use-general-page-fault-accounting.patch mm-nios2-use-general-page-fault-accounting.patch mm-openrisc-use-general-page-fault-accounting.patch mm-parisc-use-general-page-fault-accounting.patch mm-powerpc-use-general-page-fault-accounting.patch mm-riscv-use-general-page-fault-accounting.patch mm-s390-use-general-page-fault-accounting.patch mm-sh-use-general-page-fault-accounting.patch mm-sparc32-use-general-page-fault-accounting.patch mm-sparc64-use-general-page-fault-accounting.patch mm-x86-use-general-page-fault-accounting.patch mm-xtensa-use-general-page-fault-accounting.patch mm-clean-up-the-last-pieces-of-page-fault-accountings.patch mm-gup-remove-task_struct-pointer-for-all-gup-code.patch