From: Peter Xu <peterx@xxxxxxxxxx> Subject: mm/openrisc: 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. Add the missing PERF_COUNT_SW_PAGE_FAULTS perf events too. Note, the other two perf events (PERF_COUNT_SW_PAGE_FAULTS_[MAJ|MIN]) were done in handle_mm_fault(). Link: http://lkml.kernel.org/r/20200707225021.200906-15-peterx@xxxxxxxxxx Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> Acked-by: Stafford Horne <shorne@xxxxxxxxx> Cc: Jonas Bonn <jonas@xxxxxxxxxxxx> Cc: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/openrisc/mm/fault.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/arch/openrisc/mm/fault.c~mm-openrisc-use-general-page-fault-accounting +++ a/arch/openrisc/mm/fault.c @@ -15,6 +15,7 @@ #include <linux/interrupt.h> #include <linux/extable.h> #include <linux/sched/signal.h> +#include <linux/perf_event.h> #include <linux/uaccess.h> #include <asm/siginfo.h> @@ -103,6 +104,8 @@ asmlinkage void do_page_fault(struct pt_ if (in_interrupt() || !mm) goto no_context; + perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); + retry: mmap_read_lock(mm); vma = find_vma(mm, address); @@ -159,7 +162,7 @@ good_area: * 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; @@ -176,10 +179,6 @@ good_area: 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_TRIED; _
