[PATCH v4 02/26] mm/alpha: Use general page fault accounting

From: Peter Xu
Date: Tue Jun 30 2020 - 16:45:24 EST


Use the general page fault accounting by passing regs into handle_mm_fault().

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().

CC: Richard Henderson <rth@xxxxxxxxxxx>
CC: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>
CC: Matt Turner <mattst88@xxxxxxxxx>
CC: linux-alpha@xxxxxxxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/alpha/mm/fault.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index 1983e43a5e2f..09172f017efc 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -25,6 +25,7 @@
#include <linux/interrupt.h>
#include <linux/extable.h>
#include <linux/uaccess.h>
+#include <linux/perf_event.h>

extern void die_if_kernel(char *,struct pt_regs *,long, unsigned long *);

@@ -116,6 +117,7 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
#endif
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);
@@ -148,7 +150,7 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
/* If for any reason at all we couldn't handle the fault,
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;
@@ -164,10 +166,6 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
}

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