[PATCH v5 08/25] mm/ia64: Use general page fault accounting

From: Peter Xu
Date: Tue Jul 07 2020 - 18:50:47 EST


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().

Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/ia64/mm/fault.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index abf2808f9b4b..cd9766d2b6e0 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -14,6 +14,7 @@
#include <linux/kdebug.h>
#include <linux/prefetch.h>
#include <linux/uaccess.h>
+#include <linux/perf_event.h>

#include <asm/processor.h>
#include <asm/exception.h>
@@ -105,6 +106,8 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
flags |= FAULT_FLAG_USER;
if (mask & VM_WRITE)
flags |= FAULT_FLAG_WRITE;
+
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
retry:
mmap_read_lock(mm);

@@ -143,7 +146,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
* 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;
@@ -166,10 +169,6 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
}

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;

--
2.26.2