diff mbox series

[163/165] mm/xtensa: use general page fault accounting

Message ID 20200812013853.qqUeoa0Kr%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/165] percpu: return number of released bytes from pcpu_free_area() | expand

Commit Message

Andrew Morton Aug. 12, 2020, 1:38 a.m. UTC 
From: Peter Xu <peterx@redhat.com>
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@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/xtensa/mm/fault.c |   15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)
diff mbox series

Patch

--- 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..