From: Peter Xu <peterx@xxxxxxxxxx> Subject: mm/xtensa: 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. Remove the PERF_COUNT_SW_PAGE_FAULTS_[MAJ|MIN] perf events because it's now also done in handle_mm_fault(). Move the PERF_COUNT_SW_PAGE_FAULTS event higher before taking mmap_sem for the fault, then it'll match with the rest of the archs. Link: http://lkml.kernel.org/r/20200707225021.200906-24-peterx@xxxxxxxxxx Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> Acked-by: Max Filippov <jcmvbkbc@xxxxxxxxx> Cc: Chris Zankel <chris@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/xtensa/mm/fault.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) --- a/arch/xtensa/mm/fault.c~mm-xtensa-use-general-page-fault-accounting +++ a/arch/xtensa/mm/fault.c @@ -72,6 +72,9 @@ void do_page_fault(struct pt_regs *regs) if (user_mode(regs)) flags |= FAULT_FLAG_USER; + + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); + retry: mmap_read_lock(mm); vma = find_vma(mm, address); @@ -107,7 +110,7 @@ good_area: * make sure we exit gracefully rather than endlessly redo * the fault. */ - fault = handle_mm_fault(vma, address, flags, NULL); + fault = handle_mm_fault(vma, address, flags, regs); if (fault_signal_pending(fault, regs)) return; @@ -122,10 +125,6 @@ good_area: BUG(); } if (flags & FAULT_FLAG_ALLOW_RETRY) { - if (fault & VM_FAULT_MAJOR) - current->maj_flt++; - else - current->min_flt++; if (fault & VM_FAULT_RETRY) { flags |= FAULT_FLAG_TRIED; @@ -139,12 +138,6 @@ good_area: } mmap_read_unlock(mm); - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); - if (flags & VM_FAULT_MAJOR) - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs, address); - else - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs, address); - return; /* Something tried to access memory that isn't in our memory map.. _
